I've taken video of the moon with the 600D before. I found the mov format to be a pain since most astro software handles avis. Also the video is lossy compressed. I note the 7D2 now has the mp4 option which is a bit easier to handle, but don't know when they might have added this to other models. Dedicated astro video cams can output raw video so you get better quality stills out of it. I think someone made a picture style before which was flatter and more neutral which could help with later processing.
On that note, with planets, unless you have seriously big optics, they are still tiny on sensor. A bigger sensor is wasted. For example, the camera I was using is "only" 640x480 with similar pixel size to the 18MP APS-C Canon sensor. You can easily fit Jupiter on that with 6m focal length. I was trying between 4m f/20 and 6m f/30 and there isn't much in it quality wise. Yup, could use a bigger scope
Other planets are going to be smaller! Also with a dedicated astro camera, you can run at higher frame rates to increase your chances of getting good moments.
For a rough idea, below are with the astro imaging cam, not DSLR, but gives an example of what you could expect size wise. They are 100% crops. Left is my first and only serious Mars attempt though 6m f/30, and right is Jupiter at 3m f/30 (I was testing out a new scope at the time). That's with 200mm and 100mm aperture optics. If you can go bigger, there is more resolution potential.
Back to DSLR output, I don't think I ever bothered going through processing the moon video I took with the 600D, but I would say the moon would be a better choice to play with in this case.