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Contrast ratio results for LG 28" 4k

Contrast ratio 1248:1 (edge: 875:1)
Monitor model LG 28" 4k
Submitted 18 Feb 2018 04:34 CET, by 73.68.*.*
Camera model Sony SLT-A58
Processing remarks

Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 8.5 s (Set EV to +1.8)
Warning: image file 3: Underexposed. Please increase the shutter time.
Note: image file 3: suggested exposure time: 6.0 s (Set EV to +1.6)

Black
Screen photo
[open image]
Luminance 0.14 cd/m2
Luminance spread 0.06 cd/m2 (2 standard deviations)
Exposure value –4.27 stops   (aim for –2 to –3)
Exposure spread 0.61 stops
Area used for calculation 1 x 1
Camera settings Exposure time: 2.5   ISO: 100   F-number: 2.8
Focal length: 75 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 174 cd/m2
Luminance spread 74 cd/m2 (2 standard deviations)
Exposure value –2.95 stops   (aim for –2 to –3)
Exposure spread 0.62 stops
Area used for calculation 1 x 1
Camera settings Exposure time: 1/200   ISO: 100   F-number: 2.8
Focal length: 75 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.2 cd/m2
Luminance spread 0.23 cd/m2 (2 standard deviations)
Exposure value –4.08 stops   (aim for –2 to –3)
Exposure spread 1.88 stops
Area used for calculation 1 x 1
Camera settings Exposure time: 2   ISO: 100   F-number: 2.8
Focal length: 75 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.