| Contrast ratio | 530:1 | 
|---|---|
| Monitor model | |
| Submitted | 25 Sep 2011 11:54 CEST, by 112.206.*.* | 
| Camera model | Pentax K-x | 
| Processing remarks | Note: image file 1: suggested exposure time: 3.3 s (Set EV to +1.1) | 
| Black | |
| Screen photo |  | 
| Luminance | 0.14 cd/m2 | 
| Luminance spread | 0.03 cd/m2 (2 standard deviations) | 
| Exposure value | –3.55 stops (aim for –2 to –3) | 
| Exposure spread | 0.32 stops | 
| Area used for calculation | 0.375 x 0.422 | 
| Camera settings | Exposure time: 1.6   ISO: 400   F-number: 3.5 Focal length: 27 mm (35 mm equivalent) Exposure compensation: 0 | 
| White | |
| Screen photo |  | 
| Luminance | 74 cd/m2 | 
| Luminance spread | 25 cd/m2 (2 standard deviations) | 
| Exposure value | –2.5 stops (aim for –2 to –3) | 
| Exposure spread | 0.49 stops | 
| Area used for calculation | 0.375 x 0.422 | 
| Camera settings | Exposure time: 1/160   ISO: 400   F-number: 3.5 Focal length: 27 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.