577849

Benning LUXMETER Type B Manual

19
Zoom out
Zoom in
Previous page
1/40
Next page
10/ 2010
BENNING LUXMETER B
19
3.4 Photometric units conversion table
Candela [cd], Lumen [lm], Lux [lux]
lm/m2=lux(lx)
lm/cm2=phot(ph)
lm/ft2=footcandle(fc)
lm/sr=cd
Units fc and lux are dominating in the field.
Conversionbetweenfcandluxismadeaccordingtothefollowingequation:
1fc=10.764lux
3.5 FAQ: Illuminance vs Luminance
Luminanceis ameasureoftheperceived brightnessof thesourcewhenyou
look at it. The definition implies a small source, because the energy stream
fromitisdefinedasenergywithinagivensolidangle,independentofdistance
totheobserver.Ifthesourceisverysmall,atinyquartzhalogentorchbulbfor
example,the brightnesswillappeartobeintense, evenifits emissionisone
candela. If the source is, like a candle, small but not really a point, you will get
animpressionofasmallareaoflightofmoderatebrightness,eventhoughthe
light intensity is also one candela.
For measuring Luminance, the sensors must be equipped with special optics to
providethedesiredeffectiveviewingangle.
Illuminance is the light flux of one or more different light sources that are strik-
ing a certain area. Only the flux portion orthogonal to the surface is considered.
The viewingangle is180% (plane)and weightedwith thecosinus correction
function.
Example:
Themoonmaybeconsideredverymuchasapointsource.Ontheotherhand
moonlight, refracted and reflected by the atmosphere, contributes significantly
totheoverallamountoflightreachingtheearth’ssurface.Asaresultmoonlight
is a combination of a point source and a 2 π steradian area source. If you aimed
the detector directly at the moon and tracked the moon‘s path, you would be
measuring the maximum illuminance. Luminance measurements require a
narrow viewing angle(<4º) in order to satisfytheconditions underlying the
measurement units.
… 19 …


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Benning LUXMETER Type B at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Benning LUXMETER Type B in the language / languages: English, German as an attachment in your email.

The manual is 0,83 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info