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Contrast ratio of imac 27

Contrast ratio 992:1
Monitor model imac 27
Submitted 23 Mar 2013 02:26 CET, by 76.126.*.*
Camera model Olympus E-M5
Processing remarks

Note: image file 1: suggested exposure time: 2.4 s (Set EV to +1.3)

Black
Screen photo
[open image]
Luminance 0.12 cd/m2
Luminance spread 0.05 cd/m2 (2 standard deviations)
Exposure value –3.79 stops   (aim for –2 to –3)
Exposure spread 0.57 stops
Area used for calculation 0.389 x 0.437
Camera settings Exposure time: 1   ISO: 400   F-number: 2.8
Focal length: 28 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 120 cd/m2
Luminance spread 19 cd/m2 (2 standard deviations)
Exposure value –2.48 stops   (aim for –2 to –3)
Exposure spread 0.23 stops
Area used for calculation 0.389 x 0.437
Camera settings Exposure time: 1/400   ISO: 400   F-number: 2.8
Focal length: 28 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.