Contrast ratio results

Black
Contrast ratio	1376:1 (edge: 2198:1)
Monitor model
Submitted	16 Jan 2017 19:57 CET, by 5.172..
Camera model	Apple iPhone 6
Processing remarks	Warning: image file 2: Overexposed. Please decrease the shutter time. Note: image file 3: suggested exposure time: 1.1 s (Set EV to +1.2)
Screen photo	[open image]
Luminance	0.26 cd/m2
Luminance spread	0.18 cd/m2 (2 standard deviations)
Exposure value	–3.01 stops (aim for –2 to –3)
Exposure spread	1.05 stops
Area used for calculation	0.419 x 0.419
Camera settings	Exposure time: 0.5 ISO: 400 F-number: 2.2 Focal length: 29 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	355 cd/m2
Luminance spread	30 cd/m2 (2 standard deviations)
Exposure value	–0.23 stops (aim for –2 to –3)
Exposure spread	0.12 stops
Area used for calculation	0.419 x 0.419
Camera settings	Exposure time: 1/403 ISO: 400 F-number: 2.2 Focal length: 29 mm (35 mm equivalent) Exposure compensation: 0
Black at screen edge
Screen photo	[open image]
Luminance	0.16 cd/m2
Luminance spread	0.15 cd/m2 (2 standard deviations)
Exposure value	–3.68 stops (aim for –2 to –3)
Exposure spread	1.42 stops
Area used for calculation	0.419 x 0.419
Camera settings	Exposure time: 0.5 ISO: 400 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.