| Contrast ratio | 2977:1 |
|---|---|
| Monitor model | iMac 21" |
| Submitted | 01 Sep 2011 20:16 CEST, by 85.180.*.* |
| Camera model | Nikon D40 |
| Processing remarks | Warning: image file 1: Underexposed. Please increase the shutter time. |
| Black | |
| Screen photo |
|
| Luminance | 0.03 cd/m2 |
| Luminance spread | 0.02 cd/m2 (2 standard deviations) |
| Exposure value | –6.3 stops (aim for –2 to –3) |
| Exposure spread | 0.79 stops |
| Area used for calculation | 0.375 x 0.423 |
| Camera settings | Exposure time: 1 ISO: 400 F-number: 3.5 Focal length: 27 mm (35 mm equivalent) Exposure compensation: 0 |
| White | |
| Screen photo |
|
| Luminance | 99 cd/m2 |
| Luminance spread | 9 cd/m2 (2 standard deviations) |
| Exposure value | –2.4 stops (aim for –2 to –3) |
| Exposure spread | 0.14 stops |
| Area used for calculation | 0.375 x 0.423 |
| Camera settings | Exposure time: 1/200 ISO: 400 F-number: 3.5 Focal length: 27 mm (35 mm equivalent) Exposure compensation: 0 |
![[open image]](upload/cr017/04403a.jpg){kind=link}
![[open image]](upload/cr017/04403b.jpg){kind=link}
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.