I really like the video with Sigma 150-600mm lens:
I wanted to do the same, but did not want to spend 1000$ for such lens(as amazon said).
So I used 50$ 35mm C mount lens with 14$ 50X zoom lens in series:
I captured video as well, captured moon with smartphone on 7" display showing "raspistill --focus -t 0":
Nothing comparable to Sigma lens, but details can be seen with 64$ as well.