Contrast ratio results

Contrast ratio 464:1
Monitor model
Submitted 06 Feb 2009 22:50 CET, by 212.59.*.*
Camera model Canon PowerShot A510
Processing remarks

Warning: image file 2: Overexposed. Please decrease the shutter time.

Black
Screen photo
Luminance 0.84 cd/m2
Luminance spread 0.26 cd/m2 (2 standard deviations)
Exposure value –1.78 stops   (aim for –2 to –3)
Exposure spread 0.46 stops
Area used for calculation 0.5 x 0.5
Camera settings Exposure time: 1   ISO: 200   F-number: 2.6
Focal length: 34.6 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 391 cd/m2
Luminance spread 19 cd/m2 (2 standard deviations)
Exposure value –0.23 stops   (aim for –2 to –3)
Exposure spread 0.07 stops
Area used for calculation 0.5 x 0.5
Camera settings Exposure time: 1/159   ISO: 200   F-number: 2.6
Focal length: 34.6 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.