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You bring up an interesting point Phil.
I take it that the gains both Nikon and Canon are achieving in noise control come more from improvements in the supporting processing electronics and chips.
For example not to pick on SBIG but it serves as an example - the STL11 is very very noisy compared to identically chipped FLI Proline 11002. Why? Better A/D conversion probably. Now you are seeing ST8300F models with these improved electronics and SBIG is now acknowledging these available improvements and incorporating them into their newer models. No doubt STX has these improvements.
Same I suspect with DSLRs. Expeed 3 for Nikon and Digic 5+ for Canon have way more processing power. So there would be a gain there.
Plus they must be able to process perhaps more advanced noise suppression using the extra computing power available than earlier models.
There is also optimising the antialiasing filter. These filters are pretty harsh. I have changed a few over on EOS20D and also Nikon D70. They must cut down QE a lot. So optimising them must have a gain at the expense of flirting with moire.
But I know what you mean. I have a 20D and a 40D and I shot a 5D mark ii and the 40D seemed to have same or better noise performance as the 5D mark ii or at minimum it was similar. I was surprised I expected the 5D mark ii to be a lot cleaner. Both used under near identical conditions.
I guess in that case it comes down to pixel size.
Surely 36mp though must be some sort of ceiling or close to the theoretical limit. Geez, that same sized sensor in an astro camera is the Kodak KAI11002 chip and that is a mere 11mp (probably a tad less). My 16803 chipped camera is twice the sensor size of these chips and its only 16.8mp so that would be 8.3mp if it were full frame!
Yet when Kodak brought out the KAI16000 which is 16mp full frame size it seems to have been hugely unpopular in the astro world. Noone really uses it.
Greg.
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