Contrast ratio of Lenovo Thinkpad S430

Black
Contrast ratio	351:1 (edge: 442:1)
Monitor model	Lenovo Thinkpad S430
Submitted	03 Jan 2013 10:33 CET, by 199.58..
Camera model	Canon EOS 600D
Processing remarks
Screen photo	[open image]
Luminance	0.95 cd/m2
Luminance spread	1.66 cd/m2 (2 standard deviations)
Exposure value	–2.79 stops (aim for –2 to –3)
Exposure spread	3.88 stops
Area used for calculation	0.393 x 0.442
Camera settings	Exposure time: 0.4 ISO: 400 F-number: 3.5 Focal length: 28.3 mm (35 mm equivalent) Exposure compensation: 0
White
Screen photo	[open image]
Luminance	332 cd/m2
Luminance spread	178 cd/m2 (2 standard deviations)
Exposure value	–1.39 stops (aim for –2 to –3)
Exposure spread	0.79 stops
Area used for calculation	0.393 x 0.442
Camera settings	Exposure time: 1/332 ISO: 400 F-number: 3.5 Focal length: 28.3 mm (35 mm equivalent) Exposure compensation: 0
Black at screen edge
Screen photo	[open image]
Luminance	0.75 cd/m2
Luminance spread	1.36 cd/m2 (2 standard deviations)
Exposure value	–3.12 stops (aim for –2 to –3)
Exposure spread	4.25 stops
Area used for calculation	0.393 x 0.442
Camera settings	Exposure time: 0.4 ISO: 400 F-number: 3.5 Focal length: 28.3 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.