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

Contrast ratio results for Dell

Contrast ratio 485:1
Monitor model Dell
Submitted 21 Mar 2008 18:53 CET, by 65.185.*.*
Camera model Canon PowerShot A520
Processing remarks

Warning: image file 1: automatic white balance can cause inaccuracies.
image file 1: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.
Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 5.0 s (Set EV to +3.3)
Warning: image file 2: automatic white balance can cause inaccuracies.
image file 2: Warning: 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: 1/32 s (Set EV to -1.1)
Warning: Image F-number settings are not the same.

Black
Screen photo
[open image]
Luminance 0.41 cd/m2
Luminance spread 0.67 cd/m2 (2 standard deviations)
Exposure value –5.83 stops   (aim for –2 to –3)
Exposure spread 3.36 stops
Area used for calculation 0.5 x 0.5
Camera settings Exposure time: 0.5   ISO: 50   F-number: 2.6
Focal length: 34.6 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 197 cd/m2
Luminance spread 82 cd/m2 (2 standard deviations)
Exposure value –1.4 stops   (aim for –2 to –3)
Exposure spread 0.61 stops
Area used for calculation 0.5 x 0.5
Camera settings Exposure time: 1/15   ISO: 50   F-number: 4.5
Focal length: 34.6 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.