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Old 08-03-2012, 08:31 PM
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Peter Ward
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Quote:
Originally Posted by philiphart View Post
thanks Peter! i've been digging for people to describe ways the sensor may have actually improved to deliver real change.. that sounds like a plausible area of improvement. i bet you don't expect a gain of two stops though! canon do claim a slight improvement in 'photoelectric conversion rate' but it's clearly an incremental rather than revolutionary step even the way they phrase it. they also claim better 'on-chip' noise reduction which may be their way of saying what you are without revealing too much?

Phil
No problem Phil....I gave a presentation on CMOS vs CCD at CWAS
(now there's a few acronyms ) a few years ago.

There are a few other hallmarks of CMOS design...their complex architecture often shows us as weird off-axis diffraction spikes with point sources (i.e. stars)...& I see back illuminated CMOS are now coming on line to mittigate this as well as improve QE

However, pixel to pixel read-up variation has always been the bane of CMOS design.

Canon may now have tackled this at a wafer fabrication level, rather than calibration look-up tables, as well as using a full field micro-lens to achieve a few Db gain with similar noise reduction.

In short, I don't think it's all smoke and mirrors.
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