|
Ah, the joys of a Newt. Perfect for imaging though, and seriously under-rated.
I set mine up specifically like that. I used a shortish focuser, and placed the primary where it needed to be, so my Canon would just come to (prime) focus. I then use eyepieces at the outer end of the focuser travel, and to date have not required an extension tube (but a very short one is an option).
In your case, where you are not building from scratch, both choices are possible. Place the camera in the focuser, and make sure it is as low as possible (in an earlier scope I actually lathed the T ring down to 2" so it too slipped into the focuser, saving a few mm's). Tie the tube down and point it at a distant object. Now with the camera in place, have someone carefully slip the primary in it's cell forward a bit. You may find, if you are lucky that it doesn't need to move at all, but most likely it will need to move an inch or two. When the distant object is perfectly in focus, mark the new position of the attachment bolts/screws and this is where the primary needs to be.
This requires you make new holes in the tube, and perhaps you don't want to do this.
The other alternative is to change focusers. If you do, first check the minimum height of your existing focuser. Measure from the tube wall to the top of the focuser with it in it's min position. Let me know what this height is. We can then cast the eyes around for a shorter version, and I have been down this route as well. Really it all depends on how keen you are to hack the tube, and what the budget is. Also, if your current focuser is very short already then this isn't a viable option.
Gary
|