[gregbradley]

There are actually 3 chips, the ICX694 at 6.1mp, the ICX834 at 9mp and there is now a 12mp version. All about the same size physically around 12 x 10mm. The 694 has 4.54 micron pixels , 5 electron read noise and
77% QE (they all have 77% peak QE) and very sensitive in O111 (twice that of KAF6303). Full well is around 18,000 (the weak point). ICX834 3.69 micron pixels 77% QE with lower full well not sure what but around 12-14,000K.

The 12mp has 3 electrons read noise 77% QE and 3.1 micron pixels.Its the Sony ICX834.

Not sure what setup you'd use the 12mp, perhaps an FSQ with reducer.

The 834 chip is more for widefield refractors and the 694 is kind of handy all round. Binning 4.54 micron pixels of the 694 gives you back your 9 micron pixels but lower noise again.

KAF8300 versus Sony ICX694 - similar results at the end of the day with the Sony being better suited to narrowband where it really shines. The Sony helps with higher QE and lower read noise requiring less total exposure. It also does not need darks, flats and bias if your filters and camera is clean (darks and flats actually make the images more noisy - hard to believe until you try it several times). So the marketing claim they don't require flats and darks is somewhat true within limitations.
The small sensor size does help with image scale if you want to use a shortish focal length scope to image a galaxy. FLI Microline 694 gets the read noise down to 3 electrons. KAF8300 is higher, hard to find out what but typically Kodak chips have 9-12 electron read noise.

The KAF8300 has about 30% greater field of view at 17.96 x 13.52mm size. Its currently the most popular sensor being used. You see it listed on many many images. Its a proven performer. 56-60% QE is good as well.
KAF8300 does not bin properly at 2x2 so you don't get the full benefits of binning. The ICX694 does bin correctly with the full gains from binning.
KAF8300 has slightly lower than normal dynamic range at 64db(its often 66db) compared to the higher than Kodak 74db of the Sony. This must be from the higher read noise than normal as the sensor is supposed to have 25,500 electron well depth.

Sony has announced it is closing its CCD manufacturing to concentrate on CMOS so the future of updated CCDs seems to be over and this may be all they put out.

Both are great sensors.

Greg.