Contrast ratio results

Black
Contrast ratio	1:1
Monitor model
Submitted	30 Dec 2022 16:14 CET, by 178.46..
Camera model	OPPO CPH2127 OP4EFDL1
Processing remarks	Warning: image file 1: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. Warning: image file 1: automatic white balance can cause inaccuracies. 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: automatic white balance can cause inaccuracies. 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: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. Warning: image file 3: automatic white balance can cause inaccuracies. image file 3: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: Image ISO settings are not the same. Warning: image file 3 is too bright to be a dark photo. Maybe you mixed up the files?
Screen photo	[open image]
Luminance	493 cd/m2
Luminance spread	816 cd/m2 (2 standard deviations)
Exposure value	–1.93 stops (aim for –2 to –3)
Exposure spread	3.4 stops
Area used for calculation	0.384 x 0.513
Camera settings	Exposure time: 1/410 ISO: 90 F-number: 2.2 Focal length: 29 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	686 cd/m2
Luminance spread	1480 cd/m2 (2 standard deviations)
Exposure value	–2.4 stops (aim for –2 to –3)
Exposure spread	4.25 stops
Area used for calculation	0.384 x 0.513
Camera settings	Exposure time: 1/760 ISO: 87 F-number: 2.2 Focal length: 29 mm (35 mm equivalent) Exposure compensation: 0
Black at screen edge
Screen photo	[open image]
Luminance	1080 cd/m2
Luminance spread	790 cd/m2 (2 standard deviations)
Exposure value	–0.75 stops (aim for –2 to –3)
Exposure spread	1.11 stops
Area used for calculation	0.384 x 0.513
Camera settings	Exposure time: 1/832 ISO: 189 F-number: 2.2 Focal length: 29 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.