Contrast ratio | Test results | LCD test | Small-screen tests | Lagom home

Contrast ratio results for Dell u23

Contrast ratio 2843:1 (edge: 3552:1)
Monitor model Dell u23
Submitted 13 Jun 2017 17:34 CEST, by 79.115.*.*
Camera model Sony NEX-5N
Processing remarks

Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 9.6 s (Set EV to +4.3)
Warning: image file 3: Underexposed. Please increase the shutter time.
Note: image file 3: suggested exposure time: 12.0 s (Set EV to +4.6)
Warning: Image F-number settings are not the same.
Warning: Image focal lengths/zoom levels are not the same.

Black
Screen photo
[open image]
Luminance 0.06 cd/m2
Luminance spread 0.04 cd/m2 (2 standard deviations)
Exposure value –6.76 stops   (aim for –2 to –3)
Exposure spread 1.07 stops
Area used for calculation 0.499 x 0.564
Camera settings Exposure time: 0.5   ISO: 400   F-number: 4
Focal length: 36 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 179 cd/m2
Luminance spread 21 cd/m2 (2 standard deviations)
Exposure value –2.55 stops   (aim for –2 to –3)
Exposure spread 0.17 stops
Area used for calculation 0.374 x 0.423
Camera settings Exposure time: 1/400   ISO: 400   F-number: 3.5
Focal length: 27 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.05 cd/m2
Luminance spread 0.05 cd/m2 (2 standard deviations)
Exposure value –7.08 stops   (aim for –2 to –3)
Exposure spread 1.73 stops
Area used for calculation 0.499 x 0.564
Camera settings Exposure time: 0.5   ISO: 400   F-number: 4
Focal length: 36 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.