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

Contrast ratio results

Contrast ratio 1503:1 (edge: 413:1)
Monitor model
Submitted 26 Feb 2015 14:41 CET, by 14.198.*.*
Camera model Pentax K-7
Processing remarks

Warning: image file 1: automatic white balance can cause inaccuracies.
image file 1: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
Note: image file 1: suggested exposure time: 2.2 s (Set EV to +1.1)
Warning: image file 2: automatic white balance can cause inaccuracies.
Warning: image file 3: automatic white balance can cause inaccuracies.
image file 3: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
Warning: image file 3: Overexposed. Please decrease the shutter time.

Black
Screen photo
[open image]
Luminance 0.14 cd/m2
Luminance spread 0.1 cd/m2 (2 standard deviations)
Exposure value –3.63 stops   (aim for –2 to –3)
Exposure spread 1.07 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 1   ISO: 800   F-number: 4
Focal length: 25 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 208 cd/m2
Luminance spread 19 cd/m2 (2 standard deviations)
Exposure value –1.72 stops   (aim for –2 to –3)
Exposure spread 0.13 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 1/400   ISO: 800   F-number: 4
Focal length: 25 mm   (35 mm equivalent)
Exposure compensation: 0
Black at screen edge
Screen photo
[open image]
Luminance 0.5 cd/m2
Luminance spread 1.31 cd/m2 (2 standard deviations)
Exposure value –1.76 stops   (aim for –2 to –3)
Exposure spread 4.25 stops
Area used for calculation 0.345 x 0.398
Camera settings Exposure time: 1   ISO: 800   F-number: 4
Focal length: 25 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.