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Contrast ratio of HP nx9420

Contrast ratio 678:1
Monitor model HP nx9420
Submitted 17 May 2011 21:57 CEST, by 85.156.*.*
Camera model Canon EOS 40D
Processing remarks

Note: image file 1: suggested exposure time: 1.8 s (Set EV to +1.1)

Black
Screen photo
[open image]
Luminance 0.17 cd/m2
Luminance spread 0.23 cd/m2 (2 standard deviations)
Exposure value –3.65 stops   (aim for –2 to –3)
Exposure spread 2.4 stops
Area used for calculation 0.382 x 0.43
Camera settings Exposure time: 0.8   ISO: 400   F-number: 2.8
Focal length: 27.5 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 113 cd/m2
Luminance spread 75 cd/m2 (2 standard deviations)
Exposure value –1.54 stops   (aim for –2 to –3)
Exposure spread 1 stops
Area used for calculation 0.382 x 0.43
Camera settings Exposure time: 1/197   ISO: 400   F-number: 2.8
Focal length: 27.5 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.