Originally posted by crewl1 I have not used that scope but used to own a Pentax PF-80ED. I believe I heard that it was comparable to a 1000mm camera lens as far as range.
Your 55-300 will give you somewhere around 300-1650 mm equivalent, a slong as you don't mind looking at an LCD screen. You can also add a lcd loupe but it may get bulky.
I think for photos it is worth the effort, but as just a viewing device it may not be the handiest.
Have you looked into the Kenko lens to scope adapter? I have only read info on the internet but it may be a solution for a smaller kit.
2013 CES - Kenko LENS2SCOPE Adapter - YouTube Review of Lens2scope spotting scope adapter – and a warning I have a Lens2Scope with a K mount on order from Amazon. I plan to use it with a Pentax M 200mm lens. It will be the equivalent of a 1100mm lens on the Q. With the Lens2Scope, it will be a 20x scope.
This should be a very light, compact, and bright kit.
When the 200mm lens is attached with a K to Q adapter, it is the equivalent of a 22x scope. This is very similar to the 20x view when used with the Lens2Scope.
This kit is much easier to use for both viewing and photography than adapting a spotting scope. It should be brighter as well. It should be easier to focus.
The Pentax PF65 scope with a fixed focal length eyepiece has about a 27x view, but is about f12. One very nice thing about the Pentax fixed focal length eyepieces is that if you remove the eyecup, it reveals a 43mm thread. With a 40.5 to 43mm adapter you could attach the Q with the 01 lens attached. This is the easiest digiscoping setup I have identified.
One advantage the PF65 with the fixed eyepiece is that it is waterproof and field rugged.