Contrast ratio results

Black
Contrast ratio	1:1
Monitor model
Submitted	18 Sep 2019 22:18 CEST, by 89.64..
Camera model	Canon PowerShot A630
Processing remarks	Warning: image file 1: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. image file 1: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time. Warning: image file 2: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. image file 2: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
Screen photo	[open image]
Luminance	348 cd/m2
Luminance spread	60 cd/m2 (2 standard deviations)
Exposure value	–2.58 stops (aim for –2 to –3)
Exposure spread	0.25 stops
Area used for calculation	0.49 x 0.49
Camera settings	Exposure time: 1/1244 ISO: 400 F-number: 2.8 Focal length: 33.9 mm (35 mm equivalent) Exposure compensation: -2
White
Screen photo	[open image]
Luminance	348 cd/m2
Luminance spread	60 cd/m2 (2 standard deviations)
Exposure value	–2.58 stops (aim for –2 to –3)
Exposure spread	0.25 stops
Area used for calculation	0.49 x 0.49
Camera settings	Exposure time: 1/1244 ISO: 400 F-number: 2.8 Focal length: 33.9 mm (35 mm equivalent) Exposure compensation: -2

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.