Quote:
Originally Posted by Peter Ward
Well.... 
I'd disagree. Sony don't publish absolute QE data, and it seems derived values vary a tad depending on who's website you want to believe.
So does Christian Buil...
....his testing indicates it's more like 20% at best.
http://www.astrosurf.com/buil/isis/noise/result.htm |
...
Crikey Peter..... I thought that old myth had been put to bed years ago
.
looking at the website you linked to, 66% QE (694) actually provides 50% better sensitivity than 44% QE (8300), which is way more than "like 20% at best". Greg was talking about the system sensitivity gain you get from the higher QE, not a subtraction of absolute quantum efficiencies.
However, the extra pixel size of the 8300 will partially compensate for the lower QE and higher read noise of the 8300 (though not totally from Greg's post) and at 2x2, the bigger pixels are a better match to a 2800mm fl than those of the more expensive Sony CCDs (it is still oversampled though). Agreed that it is far from an optimum solution, but a binned Atik8300, QHY9 or similar camera would be a relatively cost effective way to start imaging with Brian's setup.
Brian, you could also have a look at the 11002 based cameras, but check how big the corrected field is on the edge11. Also be aware that the 11002 has a very low absolute QE and will give you a much less sensitive system than other possible solutions - you will be scratching for sensitivity at f10, even with 9 micron pixels.