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

Contrast ratio results

Contrast ratio 2212:1
Monitor model
Submitted 09 Jul 2011 03:03 CEST, by 85.242.*.*
Camera model Hewlett-Packard HP PhotoSmart C850 V07.3
Processing remarks

Warning: image file 1: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
image file 1: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
Warning: image file 1: Underexposed. Please increase the shutter time.
Note: image file 1: suggested exposure time: 36.7 s (Set EV to +1.7)
Warning: image file 2: could not determine angle of view; assuming 38 mm lens (35 mm equivalent).
image file 2: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen.

Black
Screen photo
[open image]
Luminance 0.03 cd/m2
Luminance spread 0.02 cd/m2 (2 standard deviations)
Exposure value –4.22 stops   (aim for –2 to –3)
Exposure spread 1.08 stops
Area used for calculation 0.528 x 0.53
Camera settings Exposure time: 11.1   ISO: 100   F-number: 2.9
Focal length: 0 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 77 cd/m2
Luminance spread 70 cd/m2 (2 standard deviations)
Exposure value –1.67 stops   (aim for –2 to –3)
Exposure spread 1.42 stops
Area used for calculation 0.528 x 0.53
Camera settings Exposure time: 1/34   ISO: 100   F-number: 2.9
Focal length: 0 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.