Contrast ratio results

Contrast ratio 247:1
Monitor model
Submitted 29 Jan 2009 20:46 CET, by 24.150.*.*
Camera model Canon EOS DIGITAL REBEL XTi
Processing remarks

Warning: image file 1: camera was zoomed in too much.
Warning: image file 2: camera was zoomed in too much.
Note: image file 2: suggested exposure time: 1/180 s (Set EV to +1.2)

Black
Screen photo
Luminance 0.34 cd/m2
Luminance spread 0.09 cd/m2 (2 standard deviations)
Exposure value –2.98 stops   (aim for –2 to –3)
Exposure spread 0.39 stops
Area used for calculation 1 x 1
Camera settings Exposure time: 1   ISO: 800   F-number: 5
Focal length: 437 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 84 cd/m2
Luminance spread 33 cd/m2 (2 standard deviations)
Exposure value –3.68 stops   (aim for –2 to –3)
Exposure spread 0.57 stops
Area used for calculation 1 x 1
Camera settings Exposure time: 1/400   ISO: 800   F-number: 5
Focal length: 437 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.