Careful with those 4 letters... A DSLR is only as good as the lens you use, and super telephoto lenses are big, heavy and expensive - 400mm is your starting point, and that will set you back at least $2300 for the old f5.6 or around $20k for the f2. 8 (2.8kg without the body...)
If you really want to go the lens/body route, you should look at mirrorless cameras rather than DSLRs. Smaller and lighter and a rapidly growing selection of smaller and lighter lenses. They are also silent if you want them to be.
Bookmarks