Contrast ratio results

Contrast ratio 271:1
Monitor model
Submitted 15 Sep 2010 20:06 CEST, by 80.47.*.*
Camera model Canon PowerShot A710 IS
Processing remarks

Note: image file 2: suggested exposure time: 1/120 s (Set EV to -1.6)

Black
Screen photo
Luminance 0.13 cd/m2
Luminance spread 0.04 cd/m2 (2 standard deviations)
Exposure value –2 stops   (aim for –2 to –3)
Exposure spread 0.44 stops
Area used for calculation 0.495 x 0.495
Camera settings Exposure time: 3.2   ISO: 408   F-number: 2.8
Focal length: 34.3 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 35 cd/m2
Luminance spread 2 cd/m2 (2 standard deviations)
Exposure value –0.92 stops   (aim for –2 to –3)
Exposure spread 0.07 stops
Area used for calculation 0.495 x 0.495
Camera settings Exposure time: 1/40   ISO: 408   F-number: 2.8
Focal length: 34.3 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.