Contrast ratio results

Black
Contrast ratio	2882:1
Monitor model
Submitted	15 Apr 2014 09:49 CEST, by 174.77..
Camera model	Canon EOS REBEL T4i
Processing remarks	Warning: image file 1: automatic white balance can cause inaccuracies. Warning: image file 1: Underexposed. Please increase the shutter time. Note: image file 1: suggested exposure time: 5.0 s (Set EV to +4.3) Warning: image file 2: exposure time below 1/500 sec is unreliable. Try increasing the EV compensation. Warning: image file 2: automatic white balance can cause inaccuracies.
Screen photo	[open image]
Luminance	0.09 cd/m2
Luminance spread	0.03 cd/m2 (2 standard deviations)
Exposure value	–6.81 stops (aim for –2 to –3)
Exposure spread	0.42 stops
Area used for calculation	0.617 x 0.694
Camera settings	Exposure time: 1/4 ISO: 400 F-number: 3.5 Focal length: 44.4 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	269 cd/m2
Luminance spread	124 cd/m2 (2 standard deviations)
Exposure value	–2.94 stops (aim for –2 to –3)
Exposure spread	0.68 stops
Area used for calculation	0.617 x 0.694
Camera settings	Exposure time: 1/790 ISO: 400 F-number: 3.5 Focal length: 44.4 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.