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

Contrast ratio results for Apple iPhone 4

Contrast ratio 2833:1
Monitor model Apple iPhone 4
Submitted 11 Sep 2011 13:12 CEST, by 90.213.*.*
Camera model Sony DSC-V3
Processing remarks

image file 2: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time.
Warning: image file 2: Underexposed. Please increase the shutter time.
Note: image file 2: suggested exposure time: 140.1 s (Set EV to +4.1)

Black
Screen photo
[open image]
Luminance 0 cd/m2
Luminance spread 0 cd/m2 (2 standard deviations)
Exposure value –6.63 stops   (aim for –2 to –3)
Exposure spread 0.69 stops
Area used for calculation 0.49 x 0.49
Camera settings Exposure time: 8   ISO: 400   F-number: 2.8
Focal length: 33.9 mm   (35 mm equivalent)
Exposure compensation: 0
White
Screen photo
[open image]
Luminance 6 cd/m2
Luminance spread 2 cd/m2 (2 standard deviations)
Exposure value –3.48 stops   (aim for –2 to –3)
Exposure spread 0.52 stops
Area used for calculation 0.49 x 0.49
Camera settings Exposure time: 1/40   ISO: 400   F-number: 2.8
Focal length: 33.9 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.