The GoPro setup would be awesome & I have been thinking about that myself. There are a couple issues with that particular setup that I haven't figured out yet.
1- A stock GoPro doesn't have a view finder. It woulld be extremely hard to see what you're trying to film & whether or not it is actually in focus.
1a- They do make an LCD screen to put on your GoPro that would let you see what your GoPro sees however, this creates another problem. The battery life of the GoPro already sucks, I have no doubts the LCD screen will diminish what precious little battery life you have to the point of almost being useless. Or extremely frustrating anyway....
They do make an adapter to mount your smart phone to a spotting scope. Good battery life, nice sized view finder & decent video quality. This may actually be the way to go without dropping serious coin on a HD video camera with a high zoom ratio.
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