Contrast ratio results

Contrast ratio 1:1
Monitor model
Submitted 07 Sep 2009 19:37 CEST, by 189.82.*.*
Camera model Sony DSC-W55
Processing remarks

Warning: image file 1: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
Warning: image file 1: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation.
Warning: image file 1: automatic white balance can cause inaccuracies.
image file 1: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Warning: image file 1: Overexposed. Please decrease the shutter time.
Warning: image file 2: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
Warning: image file 2: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation.
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 F-number settings are not the same.
Warning: Image focal lengths/zoom levels are not the same.

Black
Screen photo
Luminance 3269 cd/m2
Luminance spread 7053 cd/m2 (2 standard deviations)
Exposure value –2.04 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.528 x 0.528
Camera settings Exposure time: 1/1250   ISO: 400   F-number: 7.1
Focal length: 0 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 3610 cd/m2
Luminance spread 7910 cd/m2 (2 standard deviations)
Exposure value –1.92 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.528 x 0.528
Camera settings Exposure time: 1/640   ISO: 400   F-number: 10
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.