Contrast ratio results

Black
Contrast ratio	10:1
Monitor model
Submitted	25 Sep 2018 19:40 CEST, by 87.214..
Camera model	Canon EOS 5D Mark IV
Processing remarks	Warning: image file 1: camera was zoomed in too much. Warning: image file 1: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. image file 1: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: image file 2: camera was zoomed in too much. image file 2: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: image file 3: camera was zoomed in too much. Warning: image file 3: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. image file 3: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: image file 3: Overexposed. Please decrease the shutter time. Warning: image file 3 is too bright to be a dark photo. Maybe you mixed up the files?
Screen photo	[open image]
Luminance	149 cd/m2
Luminance spread	268 cd/m2 (2 standard deviations)
Exposure value	–1.88 stops (aim for –2 to –3)
Exposure spread	4.25 stops
Area used for calculation	1 x 0.5
Camera settings	Exposure time: 1/400 ISO: 160 F-number: 1.6 Focal length: 189 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	1465 cd/m2
Luminance spread	2247 cd/m2 (2 standard deviations)
Exposure value	–1.58 stops (aim for –2 to –3)
Exposure spread	2.92 stops
Area used for calculation	1 x 0.5
Camera settings	Exposure time: 1/3200 ISO: 160 F-number: 1.6 Focal length: 189 mm (35 mm equivalent) Exposure compensation: 0
Black at screen edge
Screen photo	[open image]
Luminance	306 cd/m2
Luminance spread	553 cd/m2 (2 standard deviations)
Exposure value	–1.84 stops (aim for –2 to –3)
Exposure spread	4.25 stops
Area used for calculation	1 x 1
Camera settings	Exposure time: 1/800 ISO: 160 F-number: 1.6 Focal length: 189 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.