| Contrast ratio | 425:1 |
|---|---|
| Monitor model | |
| Submitted | 13 Oct 2018 14:58 CEST, by 188.37.*.* |
| Camera model | Microsoft Lumia 640 LTE |
| Processing remarks | image file 2: Note: image seems to be noisy. Try reducing the ISO setting or increasing the exposure time. |
| Black | |
| Screen photo |
|
| Luminance | 0.7 cd/m2 |
| Luminance spread | 0.46 cd/m2 (2 standard deviations) |
| Exposure value | –2.88 stops (aim for –2 to –3) |
| Exposure spread | 0.98 stops |
| Area used for calculation | 0.404 x 0.404 |
| Camera settings | Exposure time: 0.8 ISO: 100 F-number: 2.2 Focal length: 28 mm (35 mm equivalent) Exposure compensation: -7 |
| White | |
| Screen photo |
|
| Luminance | 299 cd/m2 |
| Luminance spread | 448 cd/m2 (2 standard deviations) |
| Exposure value | –1.47 stops (aim for –2 to –3) |
| Exposure spread | 2.8 stops |
| Area used for calculation | 0.404 x 0.404 |
| Camera settings | Exposure time: 1/200 ISO: 100 F-number: 2.2 Focal length: 28 mm (35 mm equivalent) Exposure compensation: -7 |
![[open image]](upload/cr049/12374a.jpg){kind=link}
![[open image]](upload/cr049/12374b.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.