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

Contrast ratio results

Contrast ratio 1329:1
Monitor model
Submitted 13 Jan 2009 00:29 CET, by 76.123.*.*
Camera model Canon PowerShot SD450
Processing remarks

Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 13.0 s (Set EV to +5.7)
Warning: image file 2: Underexposed. Please increase the shutter time.
Note: image file 2: suggested exposure time: 1/100 s (Set EV to -0.0)

Black
Screen photo
[open image]
Luminance 0.18 cd/m2
Luminance spread 0.04 cd/m2 (2 standard deviations)
Exposure value –6.2 stops   (aim for –2 to –3)
Exposure spread 0.28 stops
Area used for calculation 0.497 x 0.497
Camera settings Exposure time: 1   ISO: 50   F-number: 2.8
Focal length: 34.4 mm   (35 mm equivalent)
Exposure compensation: 2
White
Screen photo
[open image]
Luminance 243 cd/m2
Luminance spread 54 cd/m2 (2 standard deviations)
Exposure value –4.48 stops   (aim for –2 to –3)
Exposure spread 0.32 stops
Area used for calculation 0.497 x 0.497
Camera settings Exposure time: 1/403   ISO: 50   F-number: 2.8
Focal length: 34.4 mm   (35 mm equivalent)
Exposure compensation: -2

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.