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Contrast ratio results for LG 25um58

Contrast ratio 597:1 (edge: 462:1)
Monitor model LG 25um58
Submitted 15 Feb 2019 12:53 CET, by 120.29.*.*
Camera model Sony ILCE-7M3
Processing remarks

Note: image file 1: suggested exposure time: 1.3 s (Set EV to -1.3)
Note: image file 2: suggested exposure time: 1/470 s (Set EV to -1.9)
Warning: image file 3: Overexposed. Please decrease the shutter time.
Note: image file 3: suggested exposure time: 1.0 s (Set EV to -1.7)
Warning: Image focal lengths/zoom levels are not the same.

Black
Screen photo
[open image]
Luminance 0.37 cd/m2
Luminance spread 0.08 cd/m2 (2 standard deviations)
Exposure value –1.16 stops   (aim for –2 to –3)
Exposure spread 0.33 stops
Area used for calculation 0.389 x 0.437
Camera settings Exposure time: 3.2   ISO: 400   F-number: 3.5
Focal length: 28 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 219 cd/m2
Luminance spread 16 cd/m2 (2 standard deviations)
Exposure value –0.58 stops   (aim for –2 to –3)
Exposure spread 0.1 stops
Area used for calculation 0.389 x 0.437
Camera settings Exposure time: 1/125   ISO: 400   F-number: 3.5
Focal length: 28 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.47 cd/m2
Luminance spread 0.3 cd/m2 (2 standard deviations)
Exposure value –0.79 stops   (aim for –2 to –3)
Exposure spread 0.96 stops
Area used for calculation 0.403 x 0.452
Camera settings Exposure time: 3.2   ISO: 400   F-number: 3.5
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.