OK, I have been to IISAC and asked around about astro-imaging.
looking to try the cheap option which is DSLR, Nikon body only, as I already have many Nikon lenses from my old F. Also already have Nikon adaptor for the telescope.
Looking on Ebay, but how to interpret their range??
The d70 is only slightly smaller at 23.7 x 15.5mm at 7.8um so is still comparable with the exception of the smaller pixels on the d90. The sensor type on the d70 is also a ccd rather than the current CMOS standard.
If you want a camera that works well with your collection of Nikkors make sure you check the compatibility caveats. For example, entry-level models don't support autofocus unless used with AF-I or AF-S lenses. Only pro models will support metering and hence auto-exposure with non-CPU lenses (Ai and AiS).
I reckon that a base model D40 (not D40X) is less noisy than a D70 by a long shot - I've had both. The D40 also has far less amplifier glow associated with longer exposures. They're not bad as an entry-level unit. No remote cable is a pain, but I use an IR remote without issue and just manually time. The D40 I have works with all of my Nikkor Ai lenses (all 13 of them) that I used to use on my own 1960's "F" as well. If I were looking for a new Nikon body for astro I'd be buying a D700 - a full-frame machine positioned more on the prosumer end. Great at high ISOs too - with very good noise control.
i have Nikon d90 and i have no problems with it the down side is there's no bulb mode when using the laptop to control the camera.but to day i received a wireless shutter release with timer its awesome. Ive added a photo using the d90 5x10 min exp no dark frames or flats. iso noise is good up to 1600
jks.. 
cheap on eBay. That refractor of yours was impressive John. Thx for the views.
