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

Contrast ratio results

Contrast ratio 845:1
Monitor model
Submitted 16 Oct 2011 01:53 CEST, by 2.221.*.*
Camera model Pentax K20D
Processing remarks

image file 1: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Note: image file 1: suggested exposure time: 3.2 s (Set EV to -1.6)
image file 2: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.

Black
Screen photo
[open image]
Luminance 0.19 cd/m2
Luminance spread 0.06 cd/m2 (2 standard deviations)
Exposure value –0.86 stops   (aim for –2 to –3)
Exposure spread 0.44 stops
Area used for calculation 0.375 x 0.422
Camera settings Exposure time: 10   ISO: 400   F-number: 4
Focal length: 27 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 159 cd/m2
Luminance spread 26 cd/m2 (2 standard deviations)
Exposure value –1.78 stops   (aim for –2 to –3)
Exposure spread 0.24 stops
Area used for calculation 0.375 x 0.422
Camera settings Exposure time: 1/160   ISO: 400   F-number: 4
Focal length: 27 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.