Contrast ratio results

Contrast ratio 336:1
Monitor model
Submitted 05 Apr 2008 23:59 CEST, by 169.229.*.*
Camera model Canon EOS 40D
Processing remarks

Warning: image file 1: automatic white balance can cause inaccuracies.
Note: image file 1: suggested exposure time: 1.9 s (Set EV to -1.4)
Warning: image file 2: automatic white balance can cause inaccuracies.
Note: image file 2: suggested exposure time: 1/170 s (Set EV to +1.2)
Warning: Image focal lengths/zoom levels are not the same.

Black
Screen photo
Luminance 0.41 cd/m2
Luminance spread 0.1 cd/m2 (2 standard deviations)
Exposure value –1.08 stops   (aim for –2 to –3)
Exposure spread 0.35 stops
Area used for calculation 0.653 x 0.735
Camera settings Exposure time: 5.2   ISO: 400   F-number: 4.6
Focal length: 47 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 138 cd/m2
Luminance spread 60 cd/m2 (2 standard deviations)
Exposure value –3.69 stops   (aim for –2 to –3)
Exposure spread 0.64 stops
Area used for calculation 0.63 x 0.71
Camera settings Exposure time: 1/395   ISO: 400   F-number: 4.6
Focal length: 45.4 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.