Autofocus direction change

Hi,

When I use autofocus, focuser goes OUT and then step by step IN, making V-curve. I would like to have it opposite way - is it possible in other way than using “reverse direction” checkbox?

I have little slip on my cryford when it goes IN. So when autofocus make several moves IN, I have got noticeable error.

I am not sure if I can treat it as backlash and enter backlash compensation.

I would appreciate your help.

best regards,
Lukasz

Even if you switch the direction it would need to go IN to go back to the optimal focus, doing that your focuser will probably slip and your images won’t be in focus anymore.
If your focuser slips you simply need to fix that, you won’t get good results with autofocus when there’s a mechanical problem.

Xplode

Thank you for your answer. I know that the best solution is to fix crayford, but I have run out of ideas what to do more, so I look for other solution. And no, buying new one is not an option right now :slight_smile:

Why I asked for changing direction? I have slippage only when focuser is travelling IN direction, so I understand this situation like that:

What I have during autofocus:

  • focuser travel OUT 100 steps, no slip, no errors
  • focuser travel IN 11 steps 9 times, I have 9 x slip error
  • focuser travel OUT to best focus position, no slip, no error

What I would like to have:

  • focuser travel IN 100 steps, one slip, one error
  • focuser travel OUT 11 steps 9 times, no slip, no error
  • focuser travel IN to best focus position, one slip, one error

It is not. You’d need to “Reverse Direction” and then use “OUT”, I think, to get the behavior you desire.

Thanks,
Jared