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

Contrast ratio results

Contrast ratio 853:1 (edge: 178:1)
Monitor model
Submitted 26 Feb 2015 14:51 CET, by 14.198.*.*
Camera model Pentax K-7
Processing remarks

Note: image file 1: suggested exposure time: 3.3 s (Set EV to -1.6)
Note: image file 2: suggested exposure time: 1/260 s (Set EV to -1.0)
image file 3: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.

Black
Screen photo
[open image]
Luminance 0.18 cd/m2
Luminance spread 0.07 cd/m2 (2 standard deviations)
Exposure value –0.91 stops   (aim for –2 to –3)
Exposure spread 0.53 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 10   ISO: 400   F-number: 4
Focal length: 25 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 155 cd/m2
Luminance spread 14 cd/m2 (2 standard deviations)
Exposure value –1.46 stops   (aim for –2 to –3)
Exposure spread 0.13 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 1/125   ISO: 400   F-number: 4
Focal length: 25 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.87 cd/m2
Luminance spread 3.13 cd/m2 (2 standard deviations)
Exposure value –2.97 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 0.5   ISO: 400   F-number: 4
Focal length: 25 mm   (35 mm equivalent)
Exposure compensation: 0
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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.