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Contrast ratio results for imac 21.5" 2011

Contrast ratio 1019:1
Monitor model imac 21.5" 2011
Submitted 17 Jan 2017 06:50 CET, by 154.58.*.*
Camera model Sony DSC-RX100M3
Processing remarks

Warning: Image ISO settings are not the same.

Black
Screen photo
[open image]
Luminance 0 cd/m2
Luminance spread 0 cd/m2 (2 standard deviations)
Exposure value –2.66 stops   (aim for –2 to –3)
Exposure spread 0.89 stops
Area used for calculation 0.333 x 0.375
Camera settings Exposure time: 2.5   ISO: 4000   F-number: 1.8
Focal length: 24 mm   (35 mm equivalent)
Exposure compensation: 1.7
White
Screen photo
[open image]
Luminance 4.48 cd/m2
Luminance spread 0.45 cd/m2 (2 standard deviations)
Exposure value –1.95 stops   (aim for –2 to –3)
Exposure spread 0.14 stops
Area used for calculation 0.333 x 0.375
Camera settings Exposure time: 1/400   ISO: 6400   F-number: 1.8
Focal length: 24 mm   (35 mm equivalent)
Exposure compensation: 1.7

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.