Originally posted by Ben_Edict There are 2 fundamentally different ways to connect a camera to a scope:
1. "Digiscoping" – Using a camera + lens or only the camera to shoot through a telescop + eyepiece
2. using the telescope directly as a camera lens
for 1. you need an eyepiece projection adapter like that:
ScopeTronix: Spotting Scopes and Digiscoping Adapters
Look for example at the Uni-T adaptor. If you use the camera lens it helps to screw the camera lens to the mounting adapter with the help of another threaded adapter. You get very high magnifications this way.
You can also mount the camera without lens to the eyepiece, in which case you would need a T2-to-Pentax K adapter (which is NOT the same as a M42 adapter, both have the same diameter, but different thread pitches)
for 2. you usually just need the T2-to-Pentax K adapter, as scopes, that are intended for photographic use provide either a T2 thread diectly or via an optional mounting tube.
The latter option will provide you with a tele lens of the primary focal length of the scope - but without an adjustable aperture. On the other hand, not all scopes can be used as a camera lens, depending on whether the eyepice is removable at all.
Ben
Maybe a bit late for this topic, but addressing item 1. above, that is how I do my digiscoping with my K10D and Swarovski AT-80-HD scope.
First of all, the camera lens is critical to do what I have done. (This was based on good advice from a couple digiscopers in Great Britain.) Buy the Pentax 40mm Pancake lens - it is the only one I (and at the time that these advisors) know will work to do what comes next.
Second, find a friend who is a skilled machinist or go to a machine shop and prepare to pay, and have an adapter made to fit. Mine is made from a solid cylinder of Delrin (a brand of Nylon). He bored out the inner diameter to slip over the eyepiece of the scope. Then I had bought the proper threaded sized ring to fit the threads of the larger opening in that 40mm lens, and he turned the outside diameter, on the camera end, down to slip this ring over and pinned it to the Delrin cylinder.
This allows me to thread this cylindrical adapter into the camera, then slip the assembly over the eyepiece, and its a snug fit. It's long enough so that it slips down almost to the scope body, just leaving enough space to vary the eyepiece's magnification. Incidentally, this combo does cause some vignetting if the magnification is set incorrectly, but when set at 20 to 25 X, I get the equivalent of a 1200mm to 1500mm telephoto lens.
More details available if desired.
Olin