Contrast ratio | 438:1 |
---|---|
Monitor model | Dell u221h |
Submitted | 06 Jan 2012 06:06 CET, by 96.247.*.* |
Camera model | Apple iPhone 4S |
Processing remarks | Warning: image file 1: automatic white balance can cause inaccuracies. |
Black | |
Screen photo |
|
Luminance | 0.16 cd/m2 |
Luminance spread | 0.04 cd/m2 (2 standard deviations) |
Exposure value | –8.92 stops (aim for –2 to –3) |
Exposure spread | 0.4 stops |
Area used for calculation | 0.485 x 0.55 |
Camera settings | Exposure time: 1/20 ISO: 125 F-number: 2.4 Focal length: 35 mm (35 mm equivalent) Exposure compensation: 0 |
White | |
Screen photo |
|
Luminance | 71 cd/m2 |
Luminance spread | 5 cd/m2 (2 standard deviations) |
Exposure value | –0.15 stops (aim for –2 to –3) |
Exposure spread | 0.1 stops |
Area used for calculation | 0.48 x 0.565 |
Camera settings | Exposure time: 1/20 ISO: 125 F-number: 2.4 Focal length: 35 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.