Contrast ratio results

Contrast ratio 742:1
Monitor model
Submitted 26 Feb 2010 11:56 CET, by 85.180.*.*
Camera model Canon EOS 40D
Processing remarks

Warning: image file 1: automatic white balance can cause inaccuracies.
Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 3.7 s (Set EV to +1.9)
Warning: image file 2: automatic white balance can cause inaccuracies.
Note: image file 2: suggested exposure time: 1/200 s (Set EV to +1.3)

Black
Screen photo
Luminance 0.17 cd/m2
Luminance spread 0.13 cd/m2 (2 standard deviations)
Exposure value –4.37 stops   (aim for –2 to –3)
Exposure spread 1.2 stops
Area used for calculation 0.382 x 0.43
Camera settings Exposure time: 1   ISO: 400   F-number: 4
Focal length: 27.5 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 123 cd/m2
Luminance spread 38 cd/m2 (2 standard deviations)
Exposure value –3.84 stops   (aim for –2 to –3)
Exposure spread 0.45 stops
Area used for calculation 0.382 x 0.43
Camera settings Exposure time: 1/512   ISO: 400   F-number: 4
Focal length: 27.5 mm   (35 mm equivalent)
Exposure compensation: 0

The luminance values in cd/m2 are not very reliable, since camera sensitivities can easily differ up to 50% from their nominal value. Typically, the real luminance is 30% lower than this number. The area used for calculation is chosen such that it corresponds to a viewing angle of ±14° horizontally and ±10.5° vertically, which is equivalent to viewing the screen from a distance of about 1.5 times the diagonal size.

Unfortunately, there is a lot of variation in how cameras use EXIF settings. If photos from your camera your produce unusable results, try coming back in a few days. I review submitted pictures regularly and try to fix problems.