[gregbradley]

Binning a Sony 694 gives 9 micron pixels which is ideal at 2800mm focal length.

That ideal pixel/arc sec is 1 arc second not 2 arc seconds per pixel which is really slightly oversampling. Nyquist theorem says at least 2x sampling for an efficient sample. Stan Moore suggests .5 to 1.5 arc seconds per pixel. Short focal length scopes are often imaged at 3 arc seconds or more.
A 3X sampling seems to be close to ideal and when you consider most experience seeing around 3 to 3.5 arc seconds a 3X sample is simply 3 divided by 3 = 1 arc second per pixel.

1x1 binning will work on the smaller Sony chip at 2800. I have done 3 metres. It worked better than 8300 did at that focal length because its so clean and sensitive. Its a full 30% more sensitive than the 8300 and even more when binned 2x2. The main advantage of the 8300 is the wider field of view and slightly larger well depth.

Not only is the chip cleaner, it bins properly compared to the 8300. Its more sensitive to start with so a binned 694 would cut exposure time significantly over a binned 8300 sensor.

Also the 694 being smaller is less likely to have coma in the FOV from the fairly low quality Meade or Celestron reducer. I would not be surprised if the 8300 does not correct fully with that reducer but others would know for sure.

But if you are new to astrophotography trying to image at 2800mm focal length as your first imaging setup is likely to cause you grief as an SCT has mirror flop, the focuser is a bit sloppy, your mount unless very high end is going to lack accurate enough tracking and your autoguiding solution is not likely to be ideal. The usual advice is to start with short focal length refractors in which case the 8300 or 694 are both great sensors to use and guide scopes work. Guide scopes tend not to work at 2800mm unless for quite short exposures. Off axis guiders become vital above about 800mm focal length.

At the end of the day you will get excellent results from both the Sony 694 and the Kodak 8300 sensors. The 8300 tends to be the more popular sensor as it is also a bit cheaper and a larger field of view (about 50% more than the Sony 694), is quite sensitive with reasonably low read noise.

The Sony 694 on the other hand is much cleaner, about 30% more sensitive, even more when binned, 4.54 micron pixels binned 2 x 2 gives you 9 microns which seems about perfect for longer focal lengths but it will be even more challenging for tracking as the smaller sized sensor gives you a zoom effect so objects will appear larger on the Sony sensor than the 8300 sensor. This is good for galaxies and perhaps worse for larger nebula images.

Greg.