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Contrast ratio of notebook hp nx7400

Contrast ratio 204:1
Monitor model notebook hp nx7400
Submitted 30 Aug 2009 21:13 CEST, by 78.102.*.*
Camera model Canon PowerShot A700
Processing remarks

image file 1: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
image file 2: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.

Black
Screen photo
[open image]
Luminance 0.38 cd/m2
Luminance spread 0.77 cd/m2 (2 standard deviations)
Exposure value –3.14 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.495 x 0.495
Camera settings Exposure time: 1/4   ISO: 800   F-number: 2.8
Focal length: 34.3 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 77 cd/m2
Luminance spread 12 cd/m2 (2 standard deviations)
Exposure value –2.13 stops   (aim for –2 to –3)
Exposure spread 0.22 stops
Area used for calculation 0.495 x 0.495
Camera settings Exposure time: 1/403   ISO: 800   F-number: 2.8
Focal length: 34.3 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.