Contrast ratio results

Black
Contrast ratio	2:1
Monitor model
Submitted	09 Jul 2011 13:59 CEST, by 86.185..
Camera model	Canon EOS 550D
Processing remarks	Warning: image file 1: camera was zoomed in too much. image file 1: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: image file 1: Overexposed. Please decrease the shutter time. Note: image file 1: suggested exposure time: 1/460 s (Set EV to -1.2) Warning: image file 2: camera was zoomed in too much. image file 2: Warning: image includes screen edges or something that's not a monitor. Hold the camera close to the screen. Warning: image file 2: Overexposed. Please decrease the shutter time. Warning: Image ISO settings are not the same. Warning: Image F-number settings are not the same. Warning: Image focal lengths/zoom levels are not the same.
Screen photo	[open image]
Luminance	3556 cd/m2
Luminance spread	5724 cd/m2 (2 standard deviations)
Exposure value	–1.62 stops (aim for –2 to –3)
Exposure spread	3.21 stops
Area used for calculation	1 x 0.5
Camera settings	Exposure time: 1/200 ISO: 100 F-number: 8 Focal length: 87 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	8388 cd/m2
Luminance spread	13720 cd/m2 (2 standard deviations)
Exposure value	–1.3 stops (aim for –2 to –3)
Exposure spread	3.32 stops
Area used for calculation	1 x 0.802
Camera settings	Exposure time: 1/200 ISO: 400 F-number: 22 Focal length: 154 mm (35 mm equivalent) Exposure compensation: 0

{adcode}

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.