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Contrast ratio of HP Compaq nc8430

Contrast ratio 215:1 (edge: 285:1)
Monitor model HP Compaq nc8430
Submitted 02 Sep 2008 22:12 CEST, by 213.37.*.*
Camera model Canon EOS 400D DIGITAL
Processing remarks


Black
Screen photo
[open image]
Luminance 0.59 cd/m2
Luminance spread 0.93 cd/m2 (2 standard deviations)
Exposure value –2.88 stops   (aim for –2 to –3)
Exposure spread 3.03 stops
Area used for calculation 0.39 x 0.44
Camera settings Exposure time: 0.6   ISO: 400   F-number: 3.5
Focal length: 28.1 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 128 cd/m2
Luminance spread 34 cd/m2 (2 standard deviations)
Exposure value –2.04 stops   (aim for –2 to –3)
Exposure spread 0.39 stops
Area used for calculation 0.39 x 0.44
Camera settings Exposure time: 1/200   ISO: 400   F-number: 3.5
Focal length: 28.1 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.45 cd/m2
Luminance spread 0.66 cd/m2 (2 standard deviations)
Exposure value –2.87 stops   (aim for –2 to –3)
Exposure spread 2.71 stops
Area used for calculation 0.39 x 0.44
Camera settings Exposure time: 0.8   ISO: 400   F-number: 3.5
Focal length: 28.1 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.