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Old 13-05-2016, 04:04 PM
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gregbradley is offline
Join Date: Feb 2006
Location: Sydney
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Thanks Ray.

I am not sure, is this CMOS sensor considered to be an sCMOS?

My Sony A7r2 is backside illuminated, has copper wiring instead of aluminium, is 42.4mp for full frame size and very high QE.
To get that in perspective the cheapest backside illuminated CCD camera in the FLI range is around US$30K!!!

I read one test where read noise is about .3 electrons.

So yeah read noise in CCD is way high compared to the latest Sony Exmor R sensors.

Having said that, something in the implementation is off because it gets quite bad colour noise in the shadows of high ISO long exposure. Also a general light amp glow in the lower 1/3rd. Both of these are correctable.

The Olympus sensor sounds good. But every user of Micro 4/3rds sensor complains about noise kicking in even at lowish ISO levels. So it will have to prove itself as whilst read noise may be low there can be amp glow which is fine if its stable to dark subtract out. Some of these earlier ASI cameras from what I read did not have stable amp glow (perhaps because the temp regulation is not to a temperature but to an ambient, it needs to be regulated like an Astro CCD camera to within a close range of a target temp).

If you can dark subtract the amp glow and flat field it successfully it should be good.

Perhaps the PixInsight overscan bias technique may be useful with a camera like this.

Exciting times and hopefully it works out well. I personally would prefer a Sony Exmor R sensor like in the Fuji X series (16mp APSc) or 24mp APSc sized (around 25mm x19mm).

QHY list some Sony Exmor CMOS sensors on future models. They have large pixels and are large sensors. As you say Sony are quitting CCD to concentrate on CMOS so that is likely the way of the future. Sony mirrorless sensors have probably surpassed CCDs a while ago.

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