Contrast ratio results

Contrast ratio 28624:1
Monitor model
Submitted 13 Jan 2014 13:00 CET, by 31.181.*.*
Camera model
Processing remarks

Warning: image file 1: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
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: 548.2 s (Set EV to +12.4)
Warning: image file 2: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
Warning: image file 2: automatic white balance can cause inaccuracies.
image file 2: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Warning: Image ISO settings are not the same.

Black
Screen photo
Luminance 0 cd/m2
Luminance spread 0 cd/m2 (2 standard deviations)
Exposure value –14.92 stops   (aim for –2 to –3)
Exposure spread 3.35 stops
Area used for calculation 0.528 x 0.529
Camera settings Exposure time: 1/10   ISO: 272   F-number: 2.4
Focal length: 0 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 17 cd/m2
Luminance spread 3 cd/m2 (2 standard deviations)
Exposure value –2.43 stops   (aim for –2 to –3)
Exposure spread 0.22 stops
Area used for calculation 0.528 x 0.208
Camera settings Exposure time: 1/25   ISO: 137   F-number: 2.4
Focal length: 0 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.