[JJ_SO]

Well, it's two reasons: manual focus check by visual sight, even with zebra, just sucks when the display is already at the edge of amplifying these 3 or 5 photons available at night. It's hard to tell waht is zebra and what is flickering noise. Focus by wire is worsening this: If I turn the focus ring slowly, nothing happens - at least no real difference. If I turn it a bit fast, it starts to jump for- or backward. It's highly unreliable as far as i can tell. Unpredictable acceleration and reduced sharpness control are two variables - one would be more than enough to handle.

 

If the object is close enough, I use a torch - but aiming at the stars with a torch is not helpful.