Contrast ratio results

Contrast ratio 1398:1
Monitor model
Submitted 12 Mar 2015 13:31 CET, by 125.39.*.*
Camera model Pentax K-x
Processing remarks

Note: image file 1: suggested exposure time: 2.3 s (Set EV to +1.2)

Black
Screen photo
Luminance 0.27 cd/m2
Luminance spread 0.21 cd/m2 (2 standard deviations)
Exposure value –3.67 stops   (aim for –2 to –3)
Exposure spread 1.19 stops
Area used for calculation 0.417 x 0.469
Camera settings Exposure time: 1   ISO: 400   F-number: 4
Focal length: 30 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
Luminance 375 cd/m2
Luminance spread 58 cd/m2 (2 standard deviations)
Exposure value –2.19 stops   (aim for –2 to –3)
Exposure spread 0.22 stops
Area used for calculation 0.417 x 0.469
Camera settings Exposure time: 1/500   ISO: 400   F-number: 4
Focal length: 30 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.