Thread: N86 Camera vs. N900 Camera
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titan is offline titan
2009-11-08 , 09:15
Posts: 946 | Thanked: 1,650 times | Joined on Oct 2009 @ Germany
#45
Originally Posted by attila77 View Post
Please, do the math. On the N900 (with a 1/2.5" sensor) it would become an issue at ~f/4 and above. The N900, however, has f/2.8 optics, so it's within that limit even with TWICE the pixels mentioned on the site.
aperture size is independent of optics quality, which also limits the line resolution.
The N900 may have a higher-quality Carl-Zeiss lens and I don't want to defend their
specific MP recommendations based on 2007 technology but there are definitely
physical limitations. Even the Canon marketing dept has realized that and
reduced MP from 14.7 (G10) to 10 (G11) for a 1/1.7" CCD sensor.

Efficiency factor of what ? You can't do a blanket statement like that, when different sensor technologies result in vastly different signal to noise characteristics, and noise itself is a mixture of at least a dozen different factors, thermal noise is just one of which.
It took that number from a current c't magazine article, which compares new sensor technologies. It is the ratio of incoming photons to released electrons.