[Shiraz (Ray)]

the 8300 and the Sony chips have similar dynamic ranges - the Sony spec is slightly better, but not by a whole lot.

If you are worried by overexposure of stars, reduce the length of subs - the relatively low read noise of the Sony chip will allow subs about 1/3 as long as those needed by the 8300 for the same signal to noise ratio in the integrated image. If you use short subs, you can use more of them and significantly increase the total dynamic range. Despite what you will read in advertising material and elsewhere, large pixels with deep wells are not necessarily better for dynamic range, since they are often accompanied by high read noise.

The larger pixel size of the 8300 will give you more sensitivity with the same scope, but at the cost of reduced ability to resolve the finest detail - this is not a huge issue with nebulae etc, so the 8300 is best for these targets. If you want to image fine detail in galaxies, the Sony chips will definitely do better, but the scope aperture and chromatic aberration will be the limiting factors - 110mm is not quite big enough to take full advantage of very good seeing with small targets, regardless of which chip you have. Even so, the Sony chips will produce larger galaxy images, due to their smaller pixels - the 9mp chip would be best for this type of imaging with your scope.

For clarification, the 694 does not have zero thermal noise, it is just that it is so quiet that thermal noise is not an issue after minor processing (eg hot pixel removal or dithering) - even at 0C.