Contrast ratio results

Black
Contrast ratio	972:1
Monitor model
Submitted	01 Jul 2017 08:09 CEST, by 70.170..
Camera model	Pentax Q7
Processing remarks	Warning: image file 1: automatic white balance can cause inaccuracies. Warning: image file 2: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. Warning: image file 2: automatic white balance can cause inaccuracies.
Screen photo	[open image]
Luminance	0.14 cd/m2
Luminance spread	0.06 cd/m2 (2 standard deviations)
Exposure value	–2.8 stops (aim for –2 to –3)
Exposure spread	0.64 stops
Area used for calculation	0.563 x 0.563
Camera settings	Exposure time: 0.8 ISO: 400 F-number: 1.9 Focal length: 39 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	135 cd/m2
Luminance spread	27 cd/m2 (2 standard deviations)
Exposure value	–2.52 stops (aim for –2 to –3)
Exposure spread	0.29 stops
Area used for calculation	0.563 x 0.563
Camera settings	Exposure time: 1/1000 ISO: 400 F-number: 1.9 Focal length: 39 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.