While I was researching bird photography, I noticed some people suggest using a spotting scope in front of digital camera instead of a super-telephoto lens - this technique is called digiscoping.
So far, I've understood there are such major differences when compared to using a super-telephoto (400+ mm) lens:
- a much longer focal length (1200+ mm);
- lower price;
- smaller weight;
- manual focusing only;
- zoom option when shooting through zoom eyepiece;
- smaller maximum aperture (f/8 seems to be common);
- support (e.g. tripod) is a must, which makes the equipment less maneuverable;
- need equipment for attaching and/or adapting the camera to spotting scope;
- some spotting scopes come with angled ocular - good for minimizing neck fatigue, but makes hard to follow action.
Are there any other important factors to bear in mind when deciding which way to go about birding?
I am aware of the option to get the birds closer with bait, but this question is more about photos in action other than gathering food (in air, on nest), so I'm afraid a short focal length will not do.