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Hi Rally,
An interesting thread. I agree sampling is definitely an important factor and matching pixel size to focal ratio is a well known datum. 1 arc second per pixel is one approximation that AP recommends and others use .66 arc seconds per pixel as being more specific to using the Nyquist sampling theory in application (3 times sample is better than the minimum 2X).
As far as gain goes in 8300 chip I don't know anything about that so I take your work for it.
As far as small pixels will have low well depth and thus likely to show white stars - I have seen examples of better looking stars in shorter exposures in fast scopes. Longer scopes probably less of an issue but then too long a focal length and the small pixels are no longer giving you proper sampling and as you point out you lose sensitivity. I have seen that with my own eyes and this is true.
As far as small pixels not having large dynamic range I think that has some assumptions. It is assuming the same read noise and as the post linking Christian Buils work on measuring some of these common chips you can see the Sony chip is in totally another league with lower read noise whilst higher QE. As dynamic range is a function of read noise (too much read noise and you lose differentiation between some levels of shadow or brightness).
As I thought Sony is totally out in front with clear air from other sensor manufacturers and are leaving them all in the dust. Canon is several generations behind Sony. Sony is also just going from strength to strength. They just last week signed a cross sharing of imaging patents with Aptina who has a huge number of imaging patents. Aptina often make excellent sensors for Nikon cameras for one.
So that means Sony will have access to Aotina's technology to actually increase well depth on any sensor of any pixel size. There is a video of Aptina President describing the technology.
A few years of development at this rate and we'll all be using some sort of hitech CMOS sensor unless True Sense releases some new advanced chips. Probably a while yet but I already see the signs.
My prediction is this 694 chip will be very very hard to beat and will see a lot of people switching their 8300 cameras for one or at least new buyers going to the Sony Darkside.
Greg.
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