QHY 5 II
This is my guide camera and it fits like a 1.25" eyepiece on the Tak FS 60C. Focus is obtained by sliding the camera in/out on 1st use, then 'marking' the position with the locking ring. Subsequent use of the camera just means you push in as far as the locking ring - and the camera is at focus. It is, I suppose, a low to mid-range guide & planetary camera and I have had good results and few complaints all the time I have been using this. It has an ST-4 output if required and I did try this initially, as in the photo below. I discontinued that connection though as my software, PHD2, works more comprehensibly by just using the one USB connection that also supplies power to the camera.