Manual Bresser N-150 (page 32 of 38) (English)

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Instruction Manual

R-90 · R-102 · R-127S/L · R-152S · N-130 · N-150 · N-203

Looking at or near the Sun will cause instant and irreversible damage to your eye!

GENERAL INFORMATIONS / TEILESCOPE FEATURES

Fig. 1a: The Messier series telescope including a viewfinder with LED riticle (only MON2). Optical Assembly

(Newtonian model shown).

Fig. 1b: Close up of focuser and viewfinder assembly

(Standard viewfinder for MON1 models), Newtonian

shown. For a close up of the refractor focuser

assembly, see page 10.

Fig. 1c: The Messier series heavy duty steel tripod

R = Achromatic Refractor - Refracting

telescope

N = Newtonian - Reflecting telescope

Technical Data on page 20!

WARNING!

Never use a Messier-Series Telescope to look at the Sun! Looking at or near the Sun will cause instant and irreversi-

ble damage to your eye. Eye damage is often painless, so there is no warning to the observer that damage has occur-

red until it is too late. Do not point the telescope or its viewfinder at or near the Sun. Do not look through the telesco-

pe or its viewfinder as it is moving. Children should always have adult supervision while observing.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

GENERAL INFORMATIONS / TEILESCOPE FEATURES

Fig. 1d, top:

The Messier series mount

MON2

Fig. 1d, left:

The Messier series mount

MON1

INHALTSVERZEICHNIS

IMPORTANT NOTE:

• All Bresser telescopes and accessories are under constant technical advancement. Slight changes of the product specifications,

which serve the improvement of the product, are reserved for this reason.

• No part of this manual may be reproduced, sent, transferred or be translated into another language in any form without written

permission of the Meade Instruments Europe GmbH & CO. KG. Errors and technical changes excepted.

• Please keep this guidance at hand for further looking up.

® The name „Bresser“ and the Bresser Logo are registered trademarks. „Messier“ is a trademark of the Meade Instruments Europe

GmbH & Co. KG.

Chapter Page

Messier series: Your personal

window to the universe..................................................... 5

Description of the features

................................................... 5

Getting Started! – First Steps ............................................ 8

Telescope Assembly ........................................................... 8

How to Assemble Your Telescope ..................................... 8

Balancing the Telescope .................................................. 10

Aligning the Viewfinder ..................................................... 11

Choosing an Eyepiece ......................................................13

Observation ....................................................................... 14

Observing by Moving the Telescope Manually ................ 14

Observe the Moon ........................................................... 14

Setting the Polar Home Position ...................................... 15

Maintenance ...................................................................... 16

Maintenance guidelines ...................................................... 16

Alignment (Collimation)

of the Newtonian Optical System .................................... 16

Chapter Page

Inspecting the Optics ......................................................... 18

Customer Service ............................................................... 19

Technical Data R-102, R-127 S/L und R-152 S .............. 20

Technical Data N-150, N-230, R-90 und N-130 .............. 21

Appendix A: Celestial coordinates .................................. 22

Locating the Celestial Pole ................................................. 23

Setting Circles .................................................................... 23

To use the setting circles to locate an object

not easily found by direct visual observation .................. 24

Appendix B: Latitude Chart ............................................. 25

Appendix C: Polar Alignment .......................................... 27

Adjusting the polar viewfinder ............................................ 27

Polar alignment

by using the polar viewfinder (MON 2 only)...................... 28

Appendix D: Basic astronomy ......................................... 30

Appendix E: Star maps ..................................................... 35

Looking at or near the Sun will cause instant and irreversible damage to your eye!

TELESCOPE FEATURES

Messier series: Your personal

window to the universe

The Messier series models are versatile, high-resolution telescopes.

The Messier series models offer unmatched mechanical performance.

The Messier series telescopes reveal nature in an ever-expanding level of

detail. Observe the feather structure of an eagle from 50 yards or study

the rings of the planet Saturn from a distance of 800 million miles. Focus

beyond the Solar System and observe majestic nebulae, ancient star

clusters, and remote galaxies. Messier series telescopes are instruments

fully capable of growing with your interest and can meet the requirements

of the most demanding advanced observer. Refer to Figures 1a through 1e

for the following features:

Description of the features (Fig. 1a to 1d)

1 Eyepiece Thumbscrews: Tightens the eyepiece (see 3) in place.

Tighten to a firm feel only.

2 Eyepiece Holder: Holds eyepiece in place. Holders supplied for both

1.25" and 2" eyepieces.

Diagonal Prism (not shown, achromatic refractor models only):

Provides a more comfortable right-angle viewing position. Slide the

diagonal prism directly into the eyepiece holder (see 2) and tighten

the thumbscrew on the eyepiece holder to a firm feel only. See page

10 for a photo and more information.

3 Eyepiece: Place the supplied eyepiece into the eyepiece holder or

the diagonal prism and tighten in place with the eyepiece thumbscr-

ew (see 2). The eyepiece magnifies the image collected in the optical

tube.

4 8 x 50mm Viewfinder: A low-power, wide-field sighting scope with

LED reticle that enables easy centering of objects in the telescope

eyepiece.

5 Viewfinder Collimation Screws: Use these screws to adjust the

alignment of the viewfinder.

6 Viewfinder Front Cell and Locking Ring: Adjust the front cell to

focus the viewfinder. See step 3, page 11 for more details. The view-

finder is supplied with a small dust cover placed over the front cell.

7 Viewfinder Bracket: Holds the viewfinder in place.

8 Focus Knobs: Moves the telescope’s focuser drawtube in a finely-

controlled motion to achieve precise image focus. The Messier series

telescopes can be focused on objects from a distance of about 75 ft.

to infinity. Rotate the focus knobs to focus on objects.

9 Dust Cover: Place the dust cover (not visible in photo) over the

corrector when storing the telescope.

NOTE:

The dust cover should be replaced after each observing session and the

power turned off to the telescope. Allow time for any dew that might

have collected during the observing session to evaporate prior to repla-

cing the dust cover.

10 Optical Tube: The main optical component that gathers the light from

distant objects and brings this light to a focus for examination

through the eyepiece.

11 Cradle Assembly: Attaches to mount base. See 9.

13 Cradle Ring Lock Knobs (2 pcs.) and Washers

14 Cradle Rings: Part of the cradle assembly (see 11); hold the optical

tube firmly in place.

15 Viewfinder Bracket Screws: Tighten to a firm feel to hold viewfinder

securely in place (see 4). See page 11 for more information.

16 Focus Lock Knob: Designed to prevent the focuser drawtube from

Looking at or near the Sun will cause instant and irreversible damage to your eye!

Which eyepiece is suitable for

which application? See p. 13

“choosing an eyepiece”

How do I mount the viewfinder?

See p. 9, 9/9a

How do I adjust the finderscope?

See p. 11

Want to learn more about moun-

ting the telescope? See p. 8.

TELESCOPE FEATURES

moving when a heavy accessory, such as a camera, is attached to

the focuser assembly. For normal observing with an eyepiece and

diagonal prism, it is not necessary to use the lock knob.

17 Dec. Lock: Controls the manual movement of the telescope. Turning

the Dec. lock counterclockwise unlocks the telescope enabling it to be

freely rotated by hand about the Dec. axis. Turning the Dec. lock

clockwise (to a firm feel only) tightens the lock and prevents the

telescope from being moved free, but engages the manual Dec. drive

shaft.

18 Polar Viewfinder Cap (for MON2 models only): Remove this cap when

using the polar viewfinder (see 29).

19 Declination (Dec.) Setting Circle: See APPENDIX A, page 22, for more

information.

20 Counterweight Shaft Base: Thread, along with the shaft, to the mount.

See page 8 and 10 for more information.

21 Counterweight and Counterweight Lock Knob: Counterbalances the

weight of the optical tube, and adds stability to the mount. Tighten the

lock knob on the side of the counterweight to a firm feel to prevent the

weight from sliding on the shaft.

22 Counterweight Shaft: Slide the counterweight onto this shaft (see 21).

23 Counterweight Safety Cap: Prevents the counterweight from

accidentally slipping off the end of the counterweight shaft.

24 R.A. manual Drive Assembly:

26 Latitude Adjustment:

Sets the latitude of your observing location. The

two Thandle screws work in a "push - pull" operation—as you tighten

one, loosen the other. The T-handle above the star marking on top of one

of the tripod legs is the North T-handle screw (South in the Southern

Hemisphere). The leg marked with a star must be pointed North (South

in the Southern hemisphere) during the polar alignment procedure.

With MON 1 Mounts, there’s only one latitute screw but the adjustment

is similar to the MON 2 models.

27 Fine Azimuth Control Knobs: Fine tune the side-to-side movement of

the telescope when centering Polaris in the telescope eyepiece or when

using the polar alignment viewfinder.

28 Latitude Dial: Set the latitude of the observing site on this dial using

the latitude T-handle screws. For more information see Step 6, page 12.

29 Polar Alignment Viewfinder (MON 2 only): Allows you to precisely polar

align the telescope.

30 Polar Alignment Viewfinder Reticle and LED Knob (MON 2 only):

Rotate the knob to switch on or off the LED that illuminates the reticle

within the polar alignment finder. Be sure to turn off the LED when

finished with the polar viewfinder. Powered by (factory-supplied)

batteries contained within.

31 Right Ascension (R.A.) Setting Circle: See APPENDIX A, page 22.

32 R.A. Setting Circle Lock Knob: Rotate the knob to lock the R.A.

Setting Circle in place.

33 R.A. Lock: Controls the manual movement of the telescope. Turning

the R.A. lock counterclockwise unlocks the telescope enabling it to be

freely rotated by hand about the R.A. axis. Turning the R.A. lock

clockwise (to a firm feel only) tightens the lock and prevents the

telescope from being moved free, but engages the R.A. manual shaft.

34 DEC-Antriebswelle

35 Tripod Leg Adjustment Knobs: Tighten to a firm feel to secure tripod

legs.

36 Variable Height Tripod Legs: Supports the telescope mount. Note that

one legs has a star stamped on top of it. This leg must be pointed

North (South in the Southern hemisphere) during the alignment

procedure. The mount attaches to the top of the tripod.

37 Accessory tray: Set extra eyepieces and other accessory on this

convenient tray.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

IImmppoorrttaanntt::

Before loosening the DEC lock, hold

the optical tube in place; otherwise it

might swing through and caus dama-

ge to the mount or even hurt the ope-

rator.

Want to learn more about adju-

sting the latitude scale? See p. 12,

step 6.

DEFINITION:

In this manual, you will find the terms

“right aszension (RA), Declination

(DEC), Elevation and Azimut”. These

terms are explained on p. 22

Want to learn more about the

polar finder? See p. 27.

TELESCOPE FEATURES

Tripod Leg Braces: Make the tripod more secure and stable. See Fig. 3.

Accessory Tray Thumbscrew: Attach on the top side of the tray and

tighten to a firm feel to secure the tray to the tripod and keep the tripod

stable. See How to assemble your telescope, page 8 for more

information.

40 Tripod Leg Lock Knobs (one on each leg): Loosen these knobs to slide

the inner leg extension. Tighten the knobs to a firm feel to lock in the

height of the tripod..

Looking at or near the Sun will cause instant and irreversible damage to your eye!

Messier Tips

Surf the Web

One of the most exciting resources for astronomy is the internet. The inter-

net is full of websites with new images, discoveries, and the latest astronomi-

cal information.

For example, when comet Hale-Bopp made its approach to our Sun in 1998,

astronomers around the world posted new photos daily.

You can find websites for almost any topic relating to astronomy on the internet. Try the

following key word searches: NASA, Hubble, HST, astronomy, Messier, satellite, nebula,

black hole, variable stars, etc.

CChheecckk oouutt BBrreesssseerr’’ss wweebbssiittee ffoorr tthhee llaatteesstt pprroodduucctt aanndd tteecchhnniiccaall iinnffoorrmmaattiioonn.. YYoouu’’llll

ffiinndd oouurr w

weebbssiittee aatt::

http://www.bresser.de/

HHeerree aarree ssoommee ootthheerr ssiitteess yyoouu mmiigghhtt ffiinndd iinntteerreessttiinngg::

• Sky & Telescope: http://www.Skyand Telescope.com

• Astronomy: http://www.astronomy.com

• The Starfield: http://users.nac.net/gburke/

• Astronomy Picture of the Day: http://antwrp.gsfc.nasa.goc/apod

• Heavens Above

(satellite observing information): http://www.heavens-above.com

• Photographic Atlas of the Moon: http://www.lpi.ursa.edu/research/lunar_orbiter

• Hubble Space Telescope

Public Pictures: http://oposite.stsci.edu/pubinfo/pictures.html

Getting Started! – First Steps

As you unpack your telescope, carefully note the following parts. The

assembly is shipped in separate boxes.

Telescope Assembly

• Equatorial mount with polar alignment finder

• Heavy duty, adjustable steel tube tripod with leg braces, three tripod leg

lock knobs, and a captive mount locking knob

• Complete optical tube assembly including primary mirror with dust cover

and a rack-and-pinion focuser and eyepiece holders for both 1.25" and

2" eyepiece holders, tube cradle assembly with two rings and two lock

knobs

• Eyepiece

• Counterweight and counterweight shaft. Some models include an

additional counterweight.

• 8 x 50mm or 6 x 30mm viewfinder

How to Assemble Your Telescope

The giftboxes contain the optical tube assembly and the tripod with the

equatorial mount. The accessories are located within compartments

custom-cut into the styrofoam block inserts.

1. Remove the components from the giftboxes. Remove and identify the

telescope’s equipment. Refer Figures 1a to 1f for images of the parts

and the overall assembly of your telescope. When removing the tripod

from the giftbox, hold the assembly parallel (horizontal) to the ground or

the inner tripod leg extensions will slide out as they are not locked in

place.

2. Adjust the tripod legs. Spread the tripod legs as far as they will open,

so that the leg braces are taut. See Fig. 3.

3. Attach the accessory shelf to the tripod. Place the triangular accessory

shelf on top of the leg braces so that each corner of the triangle lies

over a leg brace. Notice that there is protrusion on each leg brace.

There is a corresponding slot for each protrusion on the accessory tray.

See Fig. 4. Line up the slots with the protrusions and slide the

protrusions through the slots to hold the tray in place.

4. Attach mount to tripod base. Place the mount over the base of the

tripod with the computer control panel positioned above the tripod leg

marked with a star and with the protrusion on top of the tripod's base

positioned between the fine azimuth control knobs. See Fig. 5. Back off

the azimuth control knobs wide enough for protrusion to fit between

them. Slide the hole in the center of the underside of the mount onto

the captive mount locking bolt in the center of the base and tighten it by

turning the knob below the base. Tighten to a firm feel.

5. Attach the counterweight(s) to the counterweight shaft. Place the counter-

weight shaft base (20, Fig. 1d) over the threaded end of the shaft (22, Fig.

1d). Thread the shaft and base assembly into the hole beneath the Dec.

setting circle as depicted in Fig. 6. Look through the hole in the

counterweight and note the pin blocking the hole. Tilt the counterweight

slightly and the pin moves out of position, clearing the hole. If the pin does

not move, unscrew the counterweight lock knob slightly until the pin moves.

Unscrew the safety cap (23, Fig. 1d) from the shaft. Holding the

counterweight (21, Fig. 1d) firmly in one hand, slip the counterweight to

approximately the midpoint of the counterweight shaft (22, Fig. 1d). Tighten

the counterweight lock knob to a firm feel. Replace the safety cap.

NOTE:

If the counterweight ever slips, the safety cap (23, Fig. 1d) prevents the

counterweight from sliding entirely off the shaft. Always leave the safety

cap in place when the counterweight is on the shaft.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Fig. 3: Tripod assembly

Fig 4: Place slots in tray over prot-

rusions on leg braces

Fig. 5: Attach the mount to the tri-

pod

Locking

protrusion

leg

braces

Abb. 6: ATtach counterweight

assembly (here: MON 2)

Shaft

Safety cap

Lock knob

Counterweight

shaft base

DEC-setting circle

Mounting

thumbscrew

protrusion

fine

Azimuth

control

knobs

star

Mount

locking knob

6. Set the latitude. Setting the latitude is easier if it is set before you attach

the optical tube to the assembly. Locate the latitude dial (28, Fig. 1d); note

that there is a triangular pointer above the dial located on the mount. The

pointer is not fixed; it moves as the mount moves.

Determine the latitude of your observing location. See APPENDIX B:

LATITUDE CHART, page 25, for a list of latitudes, or check an atlas. Move

the latitude T-handle screws in order to move the mount until the pointer

points to your latitude. The two T-handle screws (MON 2 only) work in a

"push - pull" operation—as you tighten one, loosen the other. When the

pointer points at your latitude, tighten both screws until they make contact

with the mount. The MON 1 has on screw with similar operation.

At your observing site, set up the telescope assembly so that this leg

approximately faces North (or South in the Southern Hemisphere).

7. Attach the cradle assembly to the mount

–

Models R and N: Remove the

optical tube from the cradle and slide the cradle assembly (11, Fig. 1a)

onto the cradle mounting slot. See Fig. 7. The rounded base of the cradle

assembly fits into the rounded portion of the mounting slot. Tighten both

the cradle locking knob and the secondary locking knob to a firm feel.

8. Position optical tube –

Models R and N:

Unscrew the cradle ring lock

knobs (13, Fig. 1a) and open the cradle rings. While firmly holding the

optical tube (10, Fig. 1a), position it onto the cradle rings (14, Fig. 1a)

with the mid-point of the optical tube’s length lying roughly in the center

of the cradle ring assembly. Point the tube so that the front end (this

end comes shipped with the dust cover (9, Fig. 1a) over it) is oriented as

depicted in Fig. 1a. Then close the cradle rings (14, Fig. 1a) over the

optical tube. Loosely tighten the cradle ring lock knobs just to hold the

tube securely in place until you balance it. See Balancing the

telescope, page 10.

Attach viewfinder bracket

(Abb. 9b). Locate the viewfinder bracket

screws (15, Fig. 1b and Fig. 9a) and remove the nuts from the screws.

Slide the holes in the viewfinder bracket over the viewfinder bracket

screws. Replace the nuts and tighten to a firm feel only.

9a. Attach viewfinder tube:. Back off the viewfinder collimation screws (5,

Fig. 1b) and slide the viewfinder tube into the bracket. Orient the view-

finder eyepiece as depicted in Fig. 1b. Tighten the collimation screws

to a firm feel. See Aligning the viewfinder, page 11.

10. Insert the eyepiece: N models (Fig. 10a): Lift to remove the dust cap

from the eyepiece holder on the focuser assembly. Set the dust cap

aside in a safe place and replace it when you have finished observing

to protect the eyepiece assembly. Back off the eyepiece thumbscrews

(1, Fig. 1a) and insert the supplied 25mm eyepiece (3, Fig. 1a) into the

the eyepiece holder. Tighten the holder thumbscrews to a firm feel to

secure the eyepiece..

R models (Abb. 10b): Lift to remove the dust cap from the eyepiece

holder on the focuser assembly. Set the dust cap aside in a safe place

and replace it when you have finished observing to protect the

eyepiece assembly. Back off the eyepiece thumbscrews (1, Fig. 1b) and

slide the diagonal prism into the holder and tighten the thumbscrews to

a firm feel only. Insert the supplied 25mm eyepiece (3, Fig. 1b) into the

the diagonal prism. Tighten the prism's thumbscrews to a firm feel to

secure the eyepiece.

NOTE:

Two eyepiece holders are included with your telescope—for both 1.25" and

2" eyepieces.To change eyepiece holders, unscrew the attached holder

from the focuser and thread on the other holder.

11. Adjust the height of the tripod: Adjust the height of the tripod by

loosening the tripod lock knobs (Fig. 11). Extend the sliding inner

section of each tripod leg to the desired length; then tighten each knob.

Adjust the tripod to a height that is comfortable for viewing.

13. Remove Plastic from Reticle LED: The polar alignment reticle LED

(30, Fig. 1d) contains two watch batteries. The reticle's LED is shipped

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Fig. 9: Viewfinder assembly. Slide

bracket into slot.

Fig. 8: Place the optical tube in

rings and loosely tighten the crad-

le ring lock knobs.

Cradle rings

Lock

knobs

R/N

Fig. 6a: Attach counterweight

assembly (MON1)

Safety cap

Lock knob

Shaft

Counter

weight

Shaft base

DEC-setting circle

Fig. 7a: Attach cradle to base mounting

and tighten locking (MON1)

Cradle

assembly

Fig. 7: Attach cradle to base mounting

slot and tighten locking (MON2)

Cradle

assembly set

with a plastic strip between the two batteries to protect battery life.

Unthread both the thumbscrew (F) and the threaded lid (E). Remove

the plastic strip before using. Refer to the reticle assembly in Fig. 13b

and note the orientation of the batteries. Place the batteries (C) into the

battery holder (D) before inserting into the reticle container (A).

NOTE:

Remember to turn off the LED when you are not using the reticle.

Balancing the Telescope

In order for the telescope to be stable on the tripod and also for it to move

smoothly, it must be balanced. To balance the telescope, unlock the Right

Ascension or R.A. lock (33, Fig. 1d). When this axis is unlocked, the teles-

cope pivots on the R.A. axis. Later in the procedure, you will also unlock

the Declination or Dec. lock (17, Fig. 1d). When unlocked, the telescope

pivots on the Dec. axis. Most of the motion of the telescope takes place by

moving about these two axes, separately or simultaneously. Try to become

familiar with these locks and observe how the telescope moves on each

axis. To obtain a fine balance of the telescope, follow the method below:

1. Firmly hold the optical tube secure so that it cannot accidentally swing

freely. Loosen the R.A. lock (33, Fig. 1d). The optical tube now moves

freely about the R.A. axis. Rotate the telescope so that the

counterweight shaft is parallel (horizontal) to the ground.

2. Unlock the counterweight lock knob and slide the counterweight (21,

Fig. 1d) along the counterweight shaft until the telescope remains in one

position without tending to drift down in either direction. Then re-tighten

the counterweight lock knob, locking the counterweight in position.

3. Again, hold the optical tube so that it cannot accidentally swing freely.

Lock the R.A. lock (33, Fig. 1d), and unlock the Dec. lock (17, Fig. 1d).

The telescope now is able to move freely about the Dec. axis. Loosen

the cradle ring lock knobs (13, Fig. 1a) so that the main tube slides easi-

ly back and forth in the cradle rings. Move the main tube in the cradle

rings until the telescope remains in one position without tending to drift

down in either direction. Re-lock the Dec. lock (17, Fig. 1d).

The telescope is now properly balanced on both axes. Next, the viewfinder

must be aligned.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Fig. 10a: Insert eyepiece intor holder

and tighten thumbscrews.

Fig. 11: Adjust the tripod height

using the leg lock knobs.

Eyepiece

Holde

Thumbscrew

Leg lock knob

Fig. 10b: Insert eyepiece into

diagonal prism and tighten

thumbscrews.

Eyepiece

Holder

Thumbscrews

Diagonal

prism

Viewfinder

Aligning the Viewfinder

The wide field of view of the telescope's viewfinder (4, Fig. 1a) provides

an easier way to initially sight objects than the main telescope's

eyepiece (3, Fig. 1a), which has a much narrower field of view. If you

have not already attached the viewfinder to the telescope tube

assembly, follow the procedure described in step 9, page 9.

In order for the viewfinder to be useful, it must be aligned to the main

telescope, so that both the viewfinder and telescope's optical tube (10,

Fig. 1a) point at the same position in the sky. This alignment makes it

easier to find objects: First locate an object in the wide-field viewfinder,

then look into the eyepiece of the main telescope for a detailed view.

To align the viewfinder, perform steps 1 through 4 during the daytime;

perform step 5 at night. Both the 6 x 30mm and the 8 x 50mm viewfinders

align in an identical manner. Refer to Fig. 14.

1. Remove the dust covers from the optical tube and the viewfinder.

If you have not already done so, insert the low-power 25mm eyepiece (3, Fig.

1b) into the eyepiece holder of the main telescope. See step 10, page 9.

3. Look through the viewfinder eyepiece at an object at least one-half mile

away (Tip: Remove the viewfinder tube from the bracket to simplify this

operation). If the distant object is not in focus, turn the focus lock ring

counterclockwise to loosen the viewfinder front cell (6, Fig. 1b). Twist

the front cell until focus is achieved and retighten the focus lock ring.

4. Unlock the R.A. lock (33, Fig. 1d) and the Dec lock (17, Fig. 1d) so that

the telescope turns freely on both axes. Then point the main telescope

at a tall, welldefined and stationary land object (e.g., the top of a

telephone pole) at least 200 yards distant and center the object in the

telescope's eyepiece. Focus the image by turning the focus knobs (8,

Fig. 1b). Retighten the R.A. and Dec. locks.

5. Look through the viewfinder and loosen or tighten, as appropriate, one

or more of the viewfinder collimation thumbscrews (5, Fig. 1b) until the

viewfinder’s crosshairs are precisely centered on the object you

previously centered in the main telescope's eyepiece. You are now

ready to make your first observations with your telescope.

ATTENTION:

Never point the telescope directly at or near the Sun at any time!

Observing the Sun, even for the smallest fraction of a second, will

result in instant and irreversible eye damage, as well as physical

damage to the telescope itself.

6. Check this alignment on a celestial object, such as a bright star or the

Moon, and make any necessary refinements, using the method outlined

above in steps 3 and 4.

With this alignment performed, objects first located in the wide-field

viewfinder will also appear in the telescope's eyepiece.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Fig. 13a: Reticle LED assembly:

(A) Reticle container

(B) LED

(D) Battery holder

(E) Threaded lid

(F) On/off switch

ấ

Ấ

ả

Ả

ạ

Ạ

Abb. 13b: Before using the illumi-

nation for the first time, remove the

isolation pad (See Fig. 13a) from

the battery holder.

Isolation pad

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Collimation screws

Eyepiece

Fig. 14: Viewfinder alignment (MON 2

viewfinder shown)

Holder

Collimation screws

Eyepiece

Fig. 14b: Viewfinder assembly (MON

1 models shown)

Holder

Fig. 14a: LED-reticle as seen

through the MON 2 viewfinder

Messier Tips

Further Study....

This manual gives only the briefest introduction to astronomy. If you are

interested in pursuing further studies in astronomy, a few topics are suggested

below that are worth reading up on. Try looking up some of these in the optional Autostar

glossary.

Also included below is a small sampling of books, magazines, and organizations

that you might find helpful.

Topics

1. How is a star born? How does a solar system form?

2. How is the distance to a star measured? What is a light year? What is red shift and

blue shift?

3. How are the craters on our Moon formed? Is there water under the surface of the

Moon?

4. What is a black hole? A neutron star? A gamma burster? An Einstein lens?

5. What are stars made of? Why are stars different colors? How is the elementa

composition of a star determined? What is an Lyman Alpha forest?

6. What is the difference between a Type 1 and a Type II supernova?

7. What is the importance of studying the composition of comets? Where do comets

come from?

8. How old is our Sun? Will our Sun evolve into a planetary nebula or go supernova?

9. What is the Inflationary Big Bang? What is dark matter? What are MACHO's?

10. How are extrasolar planets discovered? What is an accretion (or protoplanetary) disk?

11. What are the differences between elliptical, spiral, and irregular galaxies? Can

globular clusters be older than the universe itself?

Books

1. The Guide to Amateur Astronomy by Jack Newton and Philip Teece

2. The Sky: A User’s Guide by David Levy

3. Turn Left at Orion by Guy Consolmagno & Dan Davis

4. Astrophotography for the Amateur by Michael Covington

5. Observing for the Fun of It by Melanie Melton

6. Will Black Holes Devour the Universe? and 100 Other Questions about Astronomy by

Melanie Melton

Magazines

1. Sky & Telescope, Box 9111, Belmont, MA 02178

2. Astronomy, Box 1612, Waukesha, WI 53187

Organizations

1. Astronomical League, Executive Secretary, 5675 Real del Norte, Las Cruces, NM 88012

2. The Astronomical Society of the Pacific, 390 Ashton Ave., San Francisco, CA 94112

3. The Planetary Society, 65 North Catalina Ave., Pasadena, CA 91106

Choosing an Eyepiece

A telescope’s eyepiece magnifies the image formed by the telescope’s

main optics. Each eyepiece has a focal length, expressed in millimeters,

or “mm.” The smaller the focal length, the higher the magnification. For

example, an eyepiece with a focal length of 9mm has a higher

magnification than an eyepiece with a focal length of 25mm.

Your telescope comes supplied with a Plössl 25mm eyepiece which gives

a wide, comfortable field of view with high image resolution.

Low power eyepieces offer a wide field of view, bright, high-contrast ima-

ges, and eye relief during long observing sessions. To find an object with a

telescope, always start with a lower power eyepiece such as the Super

Plössl 26mm. When the object is located and centered in the eyepiece,

you may wish to switch to a higher power eyepiece to enlarge the image

as much as practical for prevailing seeing conditions.

The power, or magnification of a telescope is determined by the focal

length of the telescope and the focal length of the eyepiece being used. To

calculate eyepiece power, divide the telescope's focal length by the

eyepiece's focal length. For example, a 25mm eyepiece is supplied with

the Messier-Series. The focal length of the 8" Messier series model is

900mm (see Specifications, page 20).

Telescope Focal Length ÷ Eyepiece Focal Length = Eyepiece Power

Telescope Focal Length = 1000mm

Eyepiece Focal Length = 25mm

Telescope Focal Length 1000 mm

Magnification = = = 40

Eyepiece Focal Length 25 mm

The magnification is therefore 40X (approximately).

Looking at or near the Sun will cause instant and irreversible damage to your eye!

FIRST STEPS

Fig. 15a+b: Jupiter; examples of

the right amount of magnification

and too much magnification

Messier Tips

Too Much Power?

Can you ever have too much power? If the type of power you’re referring to is

eyepiece magnification, yes, you can! The most common mistake of the beginning obser-

ver is to “overpower” a telescope by using high magnifications which the telescope’s

aperture and atmospheric conditions cannot reasonably support.

Keep in mind that a smaller, but bright and well-resolved image is far superior to one that

is larger, but dim and poorly resolved (see Figs. 15a and 15b). Powers above 200X

should be employed only under the steadiest atmospheric conditions.

NNoottee::

Seeing conditions vary widely

from night-tonight and site-to-site.

Turbulence in the air, even on an

apparently clear night, can distort

images. If an image appears fuzzy and

ill-defined, back off to a lower power

eyepiece for a more well-resolved

image.

(see Fig. 15a and 15b below).

Observation

Observing by Moving the Telescope Manually

After the telescope is assembled and balanced as described previously,

you are ready to begin manual observations. View easy-to-find terrestrial

objects such as street signs or traffic lights to become accustomed to the

functions and operations of the telescope. For the best results during

observations, follow the suggestions below:

• When you wish to locate an object to observe, first loosen the

telescope’s R.A. lock (33, Fig. 1d) and Dec. lock (17, Fig. 1d). The

telescope can now turn freely on its axes. Unlock each axis separately

and practice moving your telescope. Then practice with two unlocked

axes at the same time. It is very important to practice this step to

understand how your telescope moves, as the movement of an

equatorial mount is not intuitive.

• Use the aligned viewfinder to sight-in on the object you wish to observe.

When the object is centered in the viewfinder’s crosshairs, re-tighten the

R.A. and Dec. locks.

• A telescope’s eyepiece magnifies the image formed by the telescope’s

main optics. Each eyepiece has a focal length, expressed in millimeters, or

“mm.” The smaller the focal length, the higher the magnification. For

example, an eyepiece with a focal length of 9mm has a higher

magnification than an eyepiece with a focal length of 25mm. Low-power

magnification eyepieces offer a wide field of view, bright, high-contrast

images, and relief of eye strain during long observing sessions. To observe

an object with a telescope, always start with a low power eyepiece such as

the 25mm supplied with your telescope. When the object is centered and

focused in the eyepiece, switch to a higher power eyepiece to enlarge the

image as much as practical for prevailing viewing conditions.

• Once centered, an object can be focused by turning one of the knobs of

the focusing mechanism (8, Fig. 1b). Notice that when observing

astronomical objects, the field of view begins to slowly drift across the

eyepiece field. This motion is caused by the rotation of the Earth on its

axis. Objects appear to move through the field more rapidly at higher

powers. This can be compensated with the RA drive shaft or the

(optional) RA drive motor.

Observe the Moon

Point your telescope at the Moon (note that the Moon is not visible every

night). The Moon contains many interesting features, including craters,

mountain ranges, and fault lines. The best time to view the Moon is during

its crescent or half phase. Sunlight strikes the Moon at an angle during

these periods and adds a depth to the view. No shadows are seen during a

full Moon, making the overly bright surface to appear flat and rather

uninteresting. Consider the use of a neutral density Moon filter when

observing the Moon. Not only does it cut down the Moon's bright glare,

but it also enhances contrast, providing a more dramatic image.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

OBSERVATION

IImmppoorrttaanntt NNoottee::

Objects appear upside-down and

reversed left-for-right when observed

in the viewfinder. With refracting tele-

scope models, objects viewed through

the main telescope with the diagonal

mirror in place are seen right-side-up,

but reversed left-for-right. This image

inversion is of no consequence when

observing astronomical objects, and in

fact all astronomical telescopes yield

inverted images.

WWAARRNNIINNGG

Never use a Telescope to look at the

Sun! Looking at or near the Sun will

cause instant and irreversibledamage

to your eye. Eye damage is often pain-

less, so there is no warning to theob-

server that damage has occurred until

it is too late. Do not point the telesco-

pe or its viewfinder at or near the Sun.

Do not look through the telescope or

its viewfinder as it is moving. Children

should always have adult supervision

while observing.

Setting the Polar Home Position

1. Level the mount, if necessary, by adjusting the length of the three tripod

legs.

2. Unlock the R.A. Lock (33, Fig. 1d). Rotate the Optical Tube Assembly

until the counterweight shaft is pointing straight down over the mount.

See Figs. 16a and 16b.

3. If you have not already done so, lift the telescope assembly and turn it

so that the tripod leg marked with a star faces approximately North

(South in the Southern Hemisphere). Release the Dec. lock (17, Fig. 1d)

of the tripod, so that the optical tube (10, Fig. 1a) may be rotated. Rotate

the optical tube until it points North (or South in the Southern

Hemisphere). Then re-tighten the lock. Locate Polaris, the North Star, if

necessary, to use as an accurate reference for due North (or Octantis in

the Southern Hemisphere). See LOCATING THE CELESTIAL POLE,

page 23.

4. If you have not already done so, determine the latitude of your observing

location. See APPENDIX C: LATITUDE CHART, page 54, for a list of

latitudes of major cities around the world. Use the latitude T-handle

screws (26, Fig. 1d) to tilt the telescope mount so that the pointer

indicates the correct latitude of your viewing location on the latitude dial

(28, Fig. 1d). See step 6, page 12 for more information.

5. If steps 1 through 4 above were performed with reasonable accuracy,

your telescope is now sufficiently well-aligned to Polaris, the North Star,

for you to begin making observations. Once the mount has been placed

in the polar home position as described above, the latitude angle need

not be adjusted again, unless you move to a different geographical

location (i.e., a different latitude).

IMPORTANT NOTE:

For almost all astronomical observing requirements, approximate settings

of the telescope’s latitude and other settings are acceptable. Do not allow

undue attention to precise settings of polar home position of the telescope

to interfere with your basic enjoyment of the instrument.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

OBSERVATION

Fig. 16a: The polar home position,

side view.

Level

mount

Point leg

marked with

star to north

Point optical

tube to north

Point counter-

weight shaft

straight down

over mount

North

Fig. 16b: The polar home position,

front view.

MAINTENANCE AND SERVICE

Maintenance

Messier series telescopes are precision optical instruments designed to

yield a lifetime of rewarding applications. Given the care and respect due

any precision instrument, your Messier will rarely, if ever, require factory

servicing.

Maintenance guidelines include:

a. Avoid cleaning the telescope’s optics: A little dust on the front surface of

the telescope’s correcting lens causes virtually no degradation of image

quality and should not be considered reason to clean the lens.

b. When absolutely necessary, dust on the front lens should be removed

with gentle strokes of a camel hair brush or blown off with an ear syringe

(available at any pharmacy). DO NOT use a commercial photographic

lens cleaner.

c. Organic materials (e.g., fingerprints) on the front lens may be removed

with a solution of 3 parts distilled water to 1 part isopropyl alcohol. You

may also add 1 drop of biodegradable dishwashing soap per pint of

solution. Use soft, white facial tissues and make short, gentle strokes.

Change tissues often.

Caution:

Do not use scented or lotioned tissues or damage could result to the

optics.

d. If the telescope is used outdoors on a humid night, water condensation

on the telescope surfaces will probably result. While such condensation

does not normally cause any damage to the telescope, it is

recommended that the entire telescope be wiped down with a dry cloth

before the telescope is packed away. Do not, however, wipe any of the

optical surfaces. Rather, simply allow the telescope to sit for some time

in the warm indoor air, so that the wet optical surfaces can dry

unattended.

e. Do not leave your Messier inside a sealed car on a warm summer day;

excessive ambient temperatures can damage the telescope’s internal

lubrication.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

MAINTENANCE AND SERVICE

Alignment (Collimation) of the

Newtonian Optical System

All Bresser Newtonian telescopes are precisely collimated at the factory

before packing and shipment, and it is probable that you will not need to

make any optical adjustments before making observations. However, if the

telescope sustained rough handling in shipment, you may need to re-

collimate the optical system. Such re-collimation is not a difficult procedure

in any case.

The collimation procedure for the Meade Schmidt-Newtonians is slightly

different from that of other Newtonian reflecting telescopes, because of the

"fast" f/5 focal ratio of the primary mirror. In typical Newtonian reflectors with

more conventional focal ratios (i.e. longer focal ratios), when the observer

looks down the focuser tube (without an eyepiece in the focuser), the

images of the diagonal mirror, primary mirror, focuser tube, and the

observer's eye appear centered relative to each other. However, with the

short focal ratio primary mirror of the Newtonian, correct collimation requires

that the diagonal mirror be offset in 2 directions: (1) away from the focuser

and (2) towards the primary mirror, in equal amounts. This offset is

approximately 1/8" in each direction. Note that these offsets have been per-

formed at the factory prior to shipment of your telescope. It is only neces-

sary for you to confirm that the telescope has not been badly jarred out of

collimation, and to perform the final fine-tuning of Step 4, below.

Fig. 31a shows a correctly collimated Schmidt-Newtonian telescope, as it

appears when viewed through the focuser with the eyepiece removed.

To check and, if necessary, set the optical collimation, follow these steps:

1. Observe through the focuser and orient your body so that the telesco-

pe's primary mirror is to your right, and the correcting plate end of the

telescope tube is to your left. The diagonal mirror will appear centered

as shown (2, Fig. 31a). If the diagonal appears off center, then adjust the

4 collimation screws on the plastic diagonal mirror housing.

2. If the reflection of the primary mirror (3, Fig. 31a) is not centered on the

surface of the diagonal mirror, adjust the 4 collimation screws on the

plastic diagonal mirror housing to center the reflection. As described

above, the 4 collimation screws (Fig. 31b) on the plastic diagonal mirror

housing are used for two different adjustments during the collimation

procedure.

Note:

The R-(refractor) models do not need

any collimation

b c d e f g

Focuser drawtube

Secondary mirror

Reflection of primary mirror

Reflection of secondary mirror

Reflection of observer’s eye

Primary mirror clips

Fig. 31a

IMPORTANT NOTE:

Do not force the 4 screws past their normal travel, and do not rotate any

screw or screws more than 2 full turns in a counterclockwise direction (i.e.,

not more than 2 full turns in their "loosening" direction), or else the

diagonal mirror may become loosened from its support. Note that the

diagonal mirror collimation adjustments are very sensitive: generally turning

a collimation screw 1/2-turn will have a dramatic effect on collimation.

3. If the reflection of the diagonal mirror is not centered within the reflection

of the primary mirror, adjust the 3 collimation screws located on the rear

of the primary mirror cell.

NOTE:

There are 6 screws (Fig. 31c) on the primary mirror cell. The 3 knurled

knobs are the collimation screws, and the 3 smaller thumb screws are

locking screws. The locking screws must be loosened slightly in order to

adjust the collimation screws.

Proceed by "trial and error" until you develop a feel for which collimation

screw to turn in order to change the image in any given way.

4. Perform an actual star test to confirm the accuracy of steps 1 through 3.

Using the 25mm eyepiece, point the telescope at a moderately bright

(second or third magnitude) star, and center the image in the main

telescope's field of view.

5. Bring the star's image slowly in and out of focus until you see several

disks surrounding the star's center. If steps 1 through 3 were done

correctly, you will see concentric (centered with respect to each other)

circles (1, Fig. 32).

An improperly collimated instrument will reveal oblong or elongated circles

(2, Fig. 32). Adjust the 3 collimating screws on the primary mirror housing

until the circles are concentric on either side of the focus.

In summary, the 4 adjustment screws on the plastic diagonal mirror

housing change the tilt of the secondary mirror so that it is correctly

centered in the focuser drawtube, and so that the primary mirror appears

centered when looking into the focuser. The 3 collimating knobs on the

primary mirror change the tilt of the primary mirror so that it reflects the

light directly up the center of the drawtube.

Inspecting the Optics

A Note About the “Flashlight Test: If a flashlight or other high-intensity light

source is pointed down the main telescope tube, the view (depending

upon the observer’s line of sight and the angle of the light) may reveal what

appears to be scratches, dark or bright spots, or just generally uneven

coatings, giving the appearance of poor quality optics. These items are

only seen when a high intensity light is transmitted through lenses or

reflected off the mirrors, and can be seen on any high quality optical

system, including giant research telescopes.

The optical quality of a telescope cannot be judged by the “flashlight test;"

the true test of optical quality can only be conducted through careful star

testing.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

MAINTENANCE AND SERVICE

Fig 31b: The four collimation

screws on the secondary mirror

housing

Fig. 31c: The six collimation

screws on the rear of the primary

mirror cell.

knurled knob

thumbscrew

Fig. 32: Correct (1) and incorrect

(2) collimation viewed during a star

test.

1 2

Customer Service

If you have a question concerning your Messier series telescope, contact

the Messier Customer Service Department.

In the improbable case of a malfunction, please contact first the Bresser

customer service before sending back the telescope. Please give complete

error descriptions and specific information about the defective part. The

great majority of servicing issues can be resolved by telephone, avoiding

return of the telescope to the factory. In any case, we need name, address,

phone number and/or email address of the customer.

Contact data:

• Via Post:

Meade Instruments Europe GmbH & Co. KG

Messier Customer Service

Siemensstr. 6

DE-46325 Borken

Germany

New Adress from March 1st, 2006:

Gutenbergstr. 2

DE-46414 Rhede

Germany

• V

ia E-Mail:

service.apd@bresser.de

• Via T

elephone:

+49 (0) 28 61 - 93 17 60

New Telephone no. from March 1st, 2006:

+49 (0) 28 72 - 80 74 0

Looking at or near the Sun will cause instant and irreversible damage to your eye!

MAINTENANCE AND SERVICE

R-102 Achromatic refractor

Optical design achromatic refractor

Clear aperture 4” = 102 mm

Focal length 1000 mm

Focal ratio f/10

Resolving power 1.11 arc sec

Coatings multi coated

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practicle power 200x

Tripod adjustable steel-tube field tripod

Net weight 18.1 kg

R-127 S/L Achromatic refractor

Optical design achromatic refractor

Clear aperture 5” = 127 mm

Focal length 635 mm • 1200 mm

Focal ratio f/5 • f/10

Resolving power 0.9 arc sec

Coatings multi coated

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practicle power 250x

Tripod adjustable steel-tube field tripod

Net weight 20.2 kg • 21 kg

R-152 S Achromatic refractor

Optical design achromatic refractor

Clear aperture 6” = 152 mm

Focal length 760 mm

Focal ratio f/5

Resolving power 0.75 arc sec

Coatings multi coated

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practicle power 300x

Tripod adjustable steel-tube field tripod

Net weight 24.8 kg

Looking at or near the Sun will cause instant and irreversible damage to your eye!

TECHNICAL DATA

Looking at or near the Sun will cause instant and irreversible damage to your eye!

TECHNICAL DATA

N-150 Newtonian reflector

Optical design Newtonian reflector

Clear aperture 6” = 150 mm

Focal length 1200 mm

Focal ratio f/8

Resolving power 0.76 arc sec

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practical power 300x

Tripod adjustable steel-tube field tripod

Net weight 22.45 kg

N-203 Newtonian Reflector

Optical design Newtonian reflector

Clear aperture 8” = 203 mm

Focal length 900 mm

Focal ratio f/4,4

Resolving power 0.56 arc sec

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practical power 400x

Tripod adjustable steel-tube field tripod

Net weight 25.1 kg

R-90 Achromatic Refractor

Optical design achromatic refractor

Clear aperture 3,5” = 90 mm

Focal length 900 mm

Focal ratio f/10

Resolving power 1.27 arc sec

Coatings multi-coated

Mount MON2 Aluminium-Guß, German type

equatorial

RA- und DEC-Antriebssystem über flexible Wellen

Max. practical power 180x

Tripod adjustable steel-tube field tripod

Net weight 12.25 kg

N-130 Newtonian Reflector

Optical design Newtonian refelctor

Clear aperture 5,1” = 130 mm

Focal length 1000 mm

Focal ratio f/7,7

Resolving power 0.88 arc sec

Mount MON2 Aluminium-Guß, German type

equatorial

RA + DEC drive system flexible shafts

Max. practical power 260x

Tripod adjustable steel-tube field tripod

Net weight 17,3 kg

Appendix A:

Celestial coordinates

For a sufficient tracking of an celestial object, the telescope mount

has to be aligned with the celestial pole.

By doing this, the mount’s axes are orientated in this way that they fit

to the celesial sphere.

If you want to align the telescope’s mount to the celestial pole, you

need some knowledge in which way an object at the sky can be

located while it is steadily moving across the sphere. This chapter

provides a basic knowledge about equatorial coordiates, the celestial

pole and how objects can be found by their coordinates. You will also

get used to the meaning of “Right aszension” and “Declination”

A celestial coordinate system was created that maps an imaginary

sphere surrounding the Earth upon which all stars appear to be

placed. This mapping system is similar to the system of latitude and

longitude on Earth surface maps. In mapping the surface of the Earth,

lines of longitude are drawn between the North and South Poles and

lines of latitude are drawn in an East-West direction, parallel to the

Earth’s equator. Similarly, imaginary lines have been drawn to form a

latitude and longitude grid for the celestial sphere. These lines are

known as Right Ascension and Declination.

The celestial map also contains two poles and an equator just like a

map of the Earth. The poles of this coordinate system are defined as

those two points where the Earth’s north and south poles (i.e., the

Earth's axis), if extended to infinity, would cross the elestial sphere.

Thus, the North Celestial Pole (1, Fig. 34) is that point in the sky

where an extension of the North Pole intersects the celestial sphere.

The North Star, Polaris is located very near the North Celestial Pole.

The celestial equator (2, Fig. 34) is a projection of the Earth’s equator

onto the celestial sphere.

Just as an object's position on the Earth’s surface can be located by

its latitude and longitude, celestial objects may also be located using

Right Ascension and Declination. For example, you could locate Los

Angeles, California, by its latitude (+34°) and longitude (118°).

Similarly, you could locate the Ring Nebula (M57) by its Right

Ascension (18hr) and its Declination (+33°).

• Right Ascension (R.A.): This celestial version of longitude is

measured in units of hours (hr), minutes (min), and seconds (sec) on

a 24-hour "clock" (similar to how Earth's time zones are determined

by longitude lines). The "zero" line was arbitrarily chosen to pass

through the constellation Pegasus — a sort of cosmic Greenwich

meridian. R.A. coordinates range from 0hr 0min 0sec to 23hr 59min

59sec. There are 24 primary lines of R.A., located at 15-degree

intervals along the celestial equator. Objects located further and

further East of the zero R.A. grid line (0hr 0min 0sec) carry higher

R.A. coordinates.

• Declination (Dec.): This celestial version of latitude is measured in

degrees, arcminutes, and arc-seconds (e.g., 15° 27' 33"). Dec.

locations north of the celestial equator are indicated with a plus (+)

sign (e.g., the Dec. of the North celestial pole is +90°). Dec.

locations south of the celestial equator are indicated with a minus

(–) sign (e.g., the Dec. of the South celestial pole is –90°). Any point

on the celestial equator (such as the the constellations of Orion,

Virgo, and Aquarius) is said to have a Declination of zero, shown as

0° 0' 0.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX A: CELESTIAL COORDINATES

Abb. 33: Celestial sphere

Earth rotation

0° DEC

South celestial pole

Right Ascension

Star

Celestial Equator

-90° DEC

+90° DEC

Northern celestial pole

(near Polaris)

Every celestial object can be exactly determined by these

coordinates.Using setting circles prerequisites an advanced observing

technique. If you use them for the first time, first point a bright star

(the guide star) with known coordinates and adjust the setting circles

to them. Now you can do a “star hop” to the next star with known

coorditates and compare the setting circles with them. By this way,

you will learn which precise handling is necessary for a successful

pointing.

Locating the Celestial Pole

To get basic bearings at an observing location, take note of where the

Sun rises (East) and sets (West) each day. After the site is dark, face

North by pointing your left shoulder toward where the Sun set. To

precisely point at the pole, find the North Star (Polaris) by using the

Big Dipper as a guide (Fig. 35).

Note:

For nearly every purpose (except long-term astrophotography)

average settings of the mount’s azimuth and latitue are sufficient.

Therefore it is not necessary to spend too much time on perfekt

aligning the celestial pole!

Setting Circles

Setting circles included with the Messier-Series models permit the

location of faint celestial objects not easily found by direct visual

observation. With the telescope pointed at the North Celestial Pole,

the Dec. circle (19, Fig. 1d) should read 90° (understood to mean

+90°). Each division of the Dec. circle represents a 1° increment. The

R.A. circle (31, Fig. 1d) runs from 0hr to (but not including) 24hr, and

reads in increments of 5min.

Using setting circles requires a developed technique. When using the

circles for the first time, try hopping from one bright star (the

calibration star) to another bright star of known coordinates. Practice

moving the telescope from one easy-to-find object to another. In this

way, the precision required for accurate object location becomes

evident.

To use the setting circles to locate an object not

easily found by direct visual observation:

Insert a low-power eyepiece, such as a 25mm, into the focuser

assembly. Pick out a bright star with which you are familiar (or is

easily located) that is in the area of the sky in which your target

object is located. Look up the R.A. coordinate of the bright star, and

also of the object you wish to locate, in a star atlas. Point the object

at the bright star. Then loosen the R.A. setting circle lock knob (32,

Fig. 1d) and turn the R.A. setting circle to read the correct R.A.

coordinate of the bright star; lock the R.A. setting circle lock knob

onto the object. Next, loosen the R.A. lock (33, Fig. 1d) and turn the

telescope in R.A. to read the correct R.A. coordinate of the object.

Tighten the R.A. lock (33, Fig. 1d). If the procedure has been followed

carefully, the desired object should now be in the telescopic field of a

low-power eyepiece.

If you do not immediately see the object you are seeking, try

searching the adjacent sky area. Keep in mind that, with the 25mm

eyepiece, the field of view of the Messier series is about 0.5°.

Because of its much wider field, the viewfinder may be of significant

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX A: CELESTIAL COORDINATES

Abb. 34: Locating Polaris

Polaris

Ursa Minor

Ursa Maior

Cassiopeia

assistance in locating and centering objects, after the setting circles

have been used to locate the approximate position of the object.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX A: CELESTIAL COORDINATES

Messier Tips

Join an Astronomy Club. Attend a Star Party

One of the best ways to increase your knowledge of astronomy is to join an

astronomy club. Check your local newspaper, school, library, or telescope dealer/store to

find out if there’s a club in your area.

At club meetings, you will meet other astronomy and Meade enthusiasts with whom you

will be able to share your discoveries. Clubs are an excellent way to learn more about

observing the sky, to find out where the best observing sites are, and to compare notes

about telescopes, eyepieces, filters, tripods, and so forth.

Often, club members are excellent astrophotographers. Not only will you be able to see

examples of their art, but you may even be able to pick up some “tricks of the trade” to

try out on your Messier-Series telescope. Many groups also hold regularly scheduled

Star Parties at which you can check out and observe with many different telescopes and

other pieces of astronomical equipment.

APPENDIX B: LATITUDE CHART

Appendix B: Latitude Chart

Latitude Chart for Major Cities of the World

To aid in the polar alignment procedure (see pages 17-21), latitudes of

major cities around the world are listed below. To determine the latitude of

an observing site not listed on the chart, locate the city closest to your site.

Then follow the procedure below:

Northern hemisphere observers (N):

If the site is over 70 miles (110 km) north of the listed city, add one degree

for every 70 miles. If the site is over 70 miles South of the listed city,

subtract one degree per 70 miles.

Southern Hemisphere observers (S):

If the site is over 70 miles (110 km) north of the listed city, subtract one

degree for every 70 miles. If the site is over 70 miles South of the listed

city, add one degree per 70 miles.

EUROPE

City Country Latitude

Amsterdam Netherlands 52° N

Athen Greece 38° N

Berlin Germany 52° N

Bern Switzerland 47° N

Bonn Germany 50° N

Borken/Westf. Germany 52° N

Bremen Germany 53° N

Dresden Germany 51° N

Dublin Ireland 53° N

Düsseldorf Germany 51° N

Frankfurt/M. Germany 50° N

Freiburg Germany 48° N

Glasgow Scotland 56° N

Hamburg Germany 54° N

Hannover Germany 52° N

Helsinki Finland 60° N

Kopenhagen Denmark 56° N

Köln Germany 51° N

Leipzig Germany 51° N

Lissabon Portugal 39° N

London Great Britain 51° N

Madrid Spanien 40° N

München Germany 48° N

Nürnberg Germany 50° N

Oslo Norway 60° N

Paris France 49° N

Rom Italy 42° N

Saarbrücken Germany 49° N

Stockholm Schweden 59° N

Stuttgart Germany 49° N

Wien Austria 48° N

Warschau Poland 52° N

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX B: LATITUDE CHART

UNITED STATES OF AMERICA

City Country Latitude

Albuquerque New Mexico 35° N

Anchorage Alaska 61° N

Atlanta Georgia 34° N

Boston Massachusetts 42° N

Chicago Illinois 42° N

Cleveland Ohio 41° N

Dallas Texas 33° N

Denver Colorado 40° N

Detroit Michigan 42° N

Honolulu Hawaii 21° N

Jackson Mississippi 32° N

Kansas City Missouri 39° N

Las Vegas Nevada 36° N

Little Rock Arkansas 35° N

Los Angeles Kalifornien 34° N

Miami Florida 26° N

Milwaukee Wisconsin 46° N

Nashville Tennessee 36° N

New Orleans Louisiana 30° N

New York New York 41° N

Oklahoma City Oklahoma 35° N

Philadelphia Pennsylvania 40° N

Phoenix Arizona 33° N

Portland Oregon 46° N

Richmond Virginia 37° N

Salt Lake City Utah 41° N

San Antonio Texas 29° N

San Diego Kalifornien 33° N

San Francisco Kalifornien 38° N

Seattle Washington 47° N

Washington District of Columbia 39° N

Wichita Kansas 38° N

SOUTH AMERICA

City Country Latitude

Asuncion Paraguay 25° S

Brasilia Brasil 24° S

Buenos Aires Argentinia 35° S

Montevideo Uruguay 35° S

Santiago Chile 34° S

ASIA

City Country Latitude

Peking China 40° N

Seoul South Korea 37° N

Taipei Taiwan 25° N

Tokio Japan 36° N

Victoria Hongkong 23° N

AFRICA

City Country Latitude

Kairo Egypt 30° N

Cape city South Africa 34° S

Rabat Marocco 34° N

Tunis Tunesia 37° N

Windhoek Namibia 23° S

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX C: POLAR ALIGNMENT

Appendix C: Polar Alignment

The Polar Alignment Viewfinder

Normally, a rough alignment with the celestial pole is sufficient for visual

purposes. However, for those observers who need to meet the more

demanding requirements of astrophotography, the polar alignment

viewfinder allows the telescope mount to be more precisely aligned with

true North. The MON 2’s polar alignment viewfinder contains a reticle, lit by

an LED (Fig. 35 and 36).

Adjusting the polar viewfinder (MON 2 only)

A: Calibrating the month circle at the polar viewfinder

scope (best done while daytime)

1. Point the viewfinder against a bright surface (not in any case at the sun!)

and see the scaled line with the center cross (Fig. 36). Turn the

viewfinder’s eyepiece until the scales are focussed.

2. Now turn the month circle against the viewfinder until the 1st of May hits

the vertical line. The month circle is secured by a counterring; it should

be able to be turned but it should not come loose. Now you can put the

viewfinder back into the RA axis

3. On the month circle, there’s a second scale, marked “E 20 10 0 10 20

W”. Take a white pencil and mark the point on the viewfinder that is right

above the “0”. This can be also done by using a small piece of colored

tape.

B: Aligning the viewfinder’s optical axis to the RA axis

1. Starting at the polar home position (see p. 14), loosen the Dec lock, turn

the Dec axis by 90° and re-engage the Dec lock again. In this position,

the optical axis of the viewfinder is free.

2. Point the viewfinder at a terrestrial objekt like a phone pole, the tip of a

church tower or equiv. so that it lines up with the center cross of the

reticle.

3. Ascertain whether the object moves out of the center cross when the

mount is rotated around its Dec axis.

4. If this is the case, correct 50% of the error by adjusting the hex screw of

the viewfinder holder. Now correct the remaining error by repositioning

the mount. Turn the RA axis by 90 / 180° and repeat this process until

the center cross stays on the desired object.

Polar alignment by using the polar viewfinder

(MON 2 only)

1. Set the polar home position (p. 14). Loosen the Dec lock, turn the Dec

axis by 90° and re-engage the lock.

2. Loosen the RA lock (33, Fig 1 d)

3. Remove the dust caps

4. If not done yet, remove the isolaton pad from the viewfinder’s

illumination (see p. 10, step 13).

5. Turn the illuminator switch clockwise to a comfortable brightness and

look throug the viewfinder. If necessary, focus the viewfinder until reticle

and stars appear sharp.

6. In the following step 7, use the latitude adjustment screws (Fig 1 d, 26)

and the azimuth adjustment screws (Fig 1 d, 27) to do the necessary fine

adjustments

Observers on the northern hemishere:

N-7 a) Determine the rough longitude of your observing site (example:

Munich is 12° E). Now determine the longitude of the time meridian

Fig. 35: The polar alignment

viewfinder

Fig. 36: The view inside the polar

alignment viewfinder reticle (the

four stars show an association

near the southern celestial pole)

Reticle LED

knob

Eyepiece

Looking at or near the Sun will cause instant and irreversible damage to your eye!

according to your local time. For the central european time, this is 15° E

(do not use daylight savings). Calculate the difference between both

longitudes; in our exampel with Munich, it is 3°

N-7 b) Now set the secondary scale at your month ring (E 20 10...) to this

difference. If your observing site is east of the time meridian, turn to “E”,

if it is west of the meridian, turn to “W”. This setting has only to be

changed when the observing site changes by more than 2-3°.

N-7 c) Loosen the RA setting circle locking screw (32, Fig 1 d), turn the

setting circle to “0” and tighten the screw again. In normal operation,

this screw should be loose!

N-7 d) Now loosen the RA lock and turn the RA axis until the actual date at

the month match with the local time. In the picture shown, this would

e.g. be November 24th, 22:00 CET.

N-7 e) Now adjust the mount using the azimuth and latitude knobs until

Polaris fits into the small circle between 40’ and 60’.

Observers on the southern hemisphere:

S-7 a) Look at the trapezoid association in the polar viewfinder’s reticle.

They build the stars Sigma, Tau, Chi and Ypsilon Octantis. Turn the RA

axis until the “real” stars roughly cover the edge points in the trapezoid

figure.

S-7 b) Probably both trapezoids may still be parallel shifted. Adjust this

offset by using the latitude and azimuth fine controls. Maybe an

additional RA correction is necessary.

Note:

Not all settings within the month/hour scale are possible because a

german equatorial mount is limited within its movements.

8. Tighten the RA wedging again and set the telescope to its polar home

position.

Note:

Don’t forget to switch off the reticle illuminatin after use.

Fig. 37: Detail: Polar viewfinder.

APPENDIX C: POLAR ALIGNMENT

Appendix D: Basic astronomy

In the early 17th century Italian Scientist Galileo, using a telescope smaller

than your Messier, turned it skyward instead of looking at the distant trees

and mountains. What he saw, and what he realized about what he saw,

has forever changed the way mankind thinks about the universe. Imagine

what it must have been like being the first human to see moons revolve

around the planet Jupiter or to see the changing phases of Venus!

Because of his observations, Galileo correctly realized Earth's movement

and position around the Sun, and in doing so, gave birth to modern

astronomy. Yet Galileo's telescope was so crude, he could not clearly

make out the rings of Saturn.

Galileo's discoveries laid the foundation for understanding the motion and

nature of the planets, stars, and galaxies. Building on his foundation,

Henrietta Leavitt determined how to measure the distance to stars, Edwin

Hubble gave us a glimpse into the possible origin of the universe, Albert

Einstein unraveled the crucial relationship of time and light, and 21st-

century astronomers are currently discovering planets around stars outside

our solar system. Almost daily, using sophisticated successors to Galileo's

telescope, such as the Hubble Space Telescope and the Chandra X-Ray

Telescope, more and more mysteries of the universe are being probed and

understood. We are living in the golden age of astronomy. Unlike other

sciences, astronomy welcomes contributions from amateurs. Much of the

knowledge we have on subjects such as comets, meteor showers, double

and variable stars, the Moon, and our solar system comes from

observations made by amateur astronomers. So as you look through your

Bresser Messier-Series telescope, keep in mind Galileo. To him, a

telescope was not merely a machine made of glass and metal, but

something far more—a window of incredible discovery. Each glimpse offers

a potential secret waiting to be revealed.

Objects in Space

Listed below are some of the many astronomical objects that can be seen

with your Messer series telescope:

The Moon

The Moon is, on average, a distance of 239,000 miles (380,000km) from

Earth and is best observed during its crescent or half phase when Sunlight

strikes the Moon’s surface at an angle. It casts shadows and adds a sense

of depth to the view (Fig. 50).

No shadows are seen during a full Moon, causing the overly bright Moon

to appear flat and rather uninteresting through the telescope. Be sure to

use a neutral Moon filter when observing the Moon. Not only does it pro-

tect your eyes from the bright glare of the Moon, but it also helps enhance

contrast, providing a more dramatic image.

Using your Messier-Series telescope, brilliant detail can be observed on

the Moon, including hundreds of lunar craters and maria, described below.

Craters are round meteor impact sites covering most of the Moon’s surfa-

ce. With no atmosphere on the Moon, no weather conditions exist, so the

only erosive force is meteor strikes. Under these conditions, lunar craters

can last for millions of years.

Maria (plural for mare) are smooth, dark areas scattered across the lunar

surface. These dark areas are large ancient impact basins that were filled

with lava from the interior of the Moon by the depth and force of a meteor

or comet impact.

APPENDIX D: BASIC ASTRONOMY

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX D: BASIC ASTRONOMY

Twelve Apollo astronauts left their bootprints on the Moon in the late

1960's and early 1970's. However, no telescope on Earth is able to see

these footprints or any other artifacts. In fact, the smallest lunar features

that may be seen with the largest telescope on Earth are about one-half

mile across.

Planets

Planets change positions in the sky as they orbit around the Sun. To locate

the planets on a given day or month, consult a monthly astronomy

magazine, such as Sky and Telescope or Astronomy. Listed below are the

best planets for viewing through the Messier-Series.

Venus is about nine-tenths the diameter of Earth. As Venus orbits the Sun,

observers can see it go through phases (crescent, half, and full) much like

those of the Moon. The disk of Venus appears white as Sunlight is reflec-

ted off the thick cloud cover that completely obscures any surface detail.

Mars is about half the diameter of Earth, and appears through the telesco-

pe as a tiny reddish-orange disk. It may be possible to see a hint of white

at one of the planet’s Polar ice caps. Approximately every two years, when

Mars is closest to Earth in its orbit, additional detail and coloring on the

planet's surface may be visible.

Jupiter is the largest planet in our solar system and is eleven times the

diameter of Earth. The planet appears as a disk with dark lines stretching

across the surface (Fig. 43). These lines are cloud bands in the

atmosphere. Four of Jupiter’s moons (Io, Europa, Ganymede, and Callisto)

can be seen as “star-like” points of light when using even the lowest

magnification. These moons orbit Jupiter so that the number of moons

visible on any given night changes as they circle around the giant planet.

Saturn is nine times the diameter of Earth and appears as a small, round

disk with rings extending out from either side (Fig. 44). In 1610, Galileo, the

first person to observe Saturn through a telescope, did not understand that

what he was seeing were rings. Instead, he believed that Saturn had

“ears.” Saturn’s rings are composed of billions of ice particles ranging in

size from a speck of dust to the size of a house.

The major division in Saturn's rings, called the Cassini Division, is

occasionally visible through the Messier-Series. Titan, the largest of

Saturn’s moons can also be seen as a bright, star-like object near the

planet.

Deep-Sky Objects

Star charts can be used to locate constellations, individual stars and deep-

sky objects. Examples of various deep-sky objects are given below:

Stars are large gaseous objects that are self-illuminated by nuclear fusion

in their core. Because of their vast distances from our solar system, all

stars appear as pinpoints of light, irrespective of the size of the telescope

used.

Nebulae are vast interstellar clouds of gas and dust where stars are

formed. Most impressive of these is the Great Nebula in Orion (M42), a

diffuse nebula that appears as a faint wispy gray cloud. M42 is 1600 light

years from Earth. (Fig 45)

Open Clusters are loose groupings of young stars, all recently formed from

the same diffuse nebula. The Pleiades is an open cluster 410 light years

away (Fig. 46). Through the Messier-Series, numerous stars are visible.

Fig. 44: Saturn with its ring

system.

Fig. 44a: Saturn, in a higher

magnification. It has the most

extensive ring structure in our

Solar System.

Fig. 45: A favourite Winter object:

M42, the great Orion Nebula.

Looking at or near the Sun will cause instant and irreversible damage to your eye!

Constellations are large, imaginary patterns of stars believed by ancient

civilizations to be the celestial equivalent of objects, animals, people, or

gods. These patterns are too large to be seen through a telescope. To

learn the constellations, start with an easy grouping of stars, such as the

Big Dipper in Ursa Major. Then, use a star chart to explore across the sky.

Galaxies are large assemblies of stars, nebulae, and star clusters that are

bound by gravity. The most common shape is spiral (such as our own

Milky Way), but galaxies can also be elliptical, or even irregular blobs. The

Andromeda Galaxy (M31) is the closest spiral-type galaxy to our own. This

galaxy appears fuzzy and cigar-shaped. It is 2.2 million light years away in

the constellation Andromeda, located between the large “W” of Cassiopeia

and the great square of Pegasus.

A “road map” to the stars

The night sky is full of wonders and miracles. Feel free to discover the

universe; You just need to follow a few helping lines on the “road map” to

the stars!

First, find the Big Dipper, which is part of the Ursa Major constellation. It

can be found the whole year through quite easily in Europe and Northern

America.

If you draw a line on the sky which prolongs Big Dipper’s handle back-

wards, you’ll finally reach the constellation of Orion. It is remarkable by the

“Orion Belt”: three stars in a line. The great Orion Nebula is located south

of the Orion Belt It is one of the most popular objects under amateur

astronomers.

Starting at the two “pointer stars” - both stars of the back part of Big

Dipper - draw a five times prolonged line north to the pole star. If you go

ahead, you’ll finally reach the big star square that is shared by Pegasus

and Andromeda.

The summer triangle is a remarkable region left of Big Dipper’s handle. It

consists of the three bright stars Vega, Deneb and Altair.

If you prolong the shaft, you get to the constellation of Scorpio. It is

bended like a Scorpion’s tail; it also looks like the letter “J”.

American amateurs performed the words “Arc to Arcturus and spike to

Spica”. They relate to stellar region that lies in the prolonge area of Big

Dipper’s handle. Follow the arc to Arcturus, the northern hemisphere’s

brightest star and “spike” downwards to Spica, the 16th-brightest Star of

the sky.

Fig. 46: The Pleiades (M45) is one

of the most beautiful open

clusters.

Difficult to imagine stellar distances?

Learn more on p. 34

APPENDIX D: BASIC ASTRONOMY

Looking at or near the Sun will cause instant and irreversible damage to your eye!

APPENDIX D: BASIC ASTRONOMY

Fig. 47: The Andromeda Galaxy

(M31), the biggest one in our local

group.

Fig. 48

Messier-Tipps

Star Charts

Star charts and planisphere are very useful

tools and are great aids in planning a night

of celestial viewing.

A wide variety of star charts are available in

books, in magazines, on the internet and on

CD Roms. For all Messier telscopes the star

chart software „Cartes du Ciel“ is included

with your purchase.

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