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

Contrast ratio results

Contrast ratio 25:1
Monitor model
Submitted 16 Feb 2008 14:56 CET, by 86.123.*.*
Camera model Olympus C170D425
Processing remarks

Warning: using the flash makes no sense.
Warning: image file 1: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
Warning: image file 1: automatic white balance can cause inaccuracies.
Warning: image file 1: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Warning: image file 2: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
Warning: image file 2: automatic white balance can cause inaccuracies.
Warning: image file 2: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Note: image file 2: suggested exposure time: 1/530 s (Set EV to -1.1)
Warning: Image ISO settings are not the same.

Black
Screen photo
[open image]
Luminance 49 cd/m2
Luminance spread 88 cd/m2 (2 standard deviations)
Exposure value –2.03 stops   (aim for –2 to –3)
Exposure spread 4.15 stops
Area used for calculation 0.53 x 0.53
Camera settings Exposure time: 1/30   ISO: 100   F-number: 2.8
Focal length: 0 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 1245 cd/m2
Luminance spread 2263 cd/m2 (2 standard deviations)
Exposure value –1.43 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.53 x 0.53
Camera settings Exposure time: 1/250   ISO: 50   F-number: 2.8
Focal length: 0 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.