Recenter after focus


#1

I am very much looking forward to the new focus routine for long FL scopes with COs. I have an EdgeHD 14 and for now, autofocus is essentially useless at prime focus at 3910mm or with the reducer at 2737mm, though it works beautifully with the Hyperstar. Any hints on the timeframe for this?

One issue that I know I will have once the new routine is implemented is dealing with mirror shift during focus. With Hyperstar, the shift is small in comparison to the FOV, and is comparable to the shift from dithering. But at 2737mm or even more so at 3910mm, a small amount of mirror shift will substantially displace the target after focus. I know that in theory, the shift from moving focus in one direction should be canceled out by the shift from moving in the opposite direction, but in reality, this isn’t the case. For now, I just slew to a bright star to use a Bahtinov mask and then recenter the target. This works fine, but is clearly not conducive to remote imaging, which is my goal. So, I’m wondering about the feasibility of offering an option to recenter after focus.

I expect that I’ll eventually move to a Crayford focuser when imaging with the camera at the back of the scope to eliminate mirror shift altogether, but in the meantime, this feature would be very helpful.

Thanks for your consideration.

Tim


#2

None. No real work has been completed. We have been having a rash of issues dealing with general stability and those always take precedence.

Possibly… we’ll take a look. One thing at a time.


#3

Understood. No hurry. I appreciate the consideration.

Tim


www.mainsequencesoftware.com