Well I got a Bushnell 20-60x65mm the eye relief isn't the best. I tried to take video with my phone but the digital zoom was just blurry. My phone films in HD, so was sad..So I thought it would be cool to mix a phone camera with the optical zoom of the spotting scope. I ended up finding this adapter for 20$ something on amazon that you can clamp onto any scope..
This is 32ft, 20x with 4x digital zoom on a old samsung Ace 2 the lightest phone I had.
This is 32 ft no digital zoom.
Just clamps to your eye piece. I had to tape the focus knob because it kept on turning.
Its soo much nicer just to quickly look over. Also I can take pictures, video and review.
It could probably fit on a rifle scope but I think it might fall off. But maybe 22LR. Its easy to fall off, I tried it on my Mauser but as soon as cycled the action it came off.