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Contrast ratio of HP Compaq 6720s

Contrast ratio 342:1
Monitor model HP Compaq 6720s
Submitted 29 Jun 2011 21:10 CEST, by 94.132.*.*
Camera model CASIO COMPUTER CO.LTD. EX-Z90
Processing remarks

Note: image file 1: suggested exposure time: 0.6 s (Set EV to +1.5)

Black
Screen photo
[open image]
Luminance 0.66 cd/m2
Luminance spread 1.38 cd/m2 (2 standard deviations)
Exposure value –3.97 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.506 x 0.506
Camera settings Exposure time: 1/5   ISO: 400   F-number: 3.1
Focal length: 35 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 224 cd/m2
Luminance spread 72 cd/m2 (2 standard deviations)
Exposure value –1.19 stops   (aim for –2 to –3)
Exposure spread 0.47 stops
Area used for calculation 0.506 x 0.506
Camera settings Exposure time: 1/250   ISO: 400   F-number: 3.1
Focal length: 35 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.