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CometGuy
05-09-2007, 06:21 PM
This one's doing the rounds, but has major implications for amateur astrophotography:

http://www.ast.cam.ac.uk/news/luckyimaging.html

Basically, uses a technique to amplify the image signal on the sensor to a point sensor readout noise is practically non-existent. This means it will be possible to stack sub-second exposures and achieve the same signal-noise ratio as one single exposure. Autoguiders and expensive high precision mounts will become redundant and potentially higher resolution is possible (since atmospheric seeing can be frozen). Implications for planetary and deep sky imaging are enormous!

I also wouldn't be suprised to see this technology soon in consumer cameras :)

Terry

bojan
06-09-2007, 03:55 PM
Hmm basically this is the same technique widely used for planetary imaging, by stacking number of frames with, say, Registax.... The size of the optics then determines the resolution, because stacking (and adaptive optics) gets rid of atmospheric turbulence.
However, the noise of the CCD will always be the limiting factor for how faint objects we can detect. Obviously, this CCD is much better than anything used so far, but you still have to have at least couple of electrons per frame per pixel to be able to say "OK, light detected", and to have something to stack.... Otherwise you have something similar to "sampling noise" or noise that is here due to the fact that photo-electrons (and photons that creates them) are particles. There is no such thing as "noiseless" sensor.
So the size of the mirror will again be important, both for resolution and for detectability.