Bahtinov Grabber now with Autofocus !!!

[beamish]

For those of you out there with Ascom/autofocus control, the developerof the "Bahtinov Grabber" app has now added autofocus capability.

See here: Niels Noordhoek’s weblog Blog Archive Bahtinov based autofocus

Karlo

[rikyuu]

Excellent, thanks for the heads up. Just tried it on my focusing image below and the error was 0.54pixels. I guess I could have got it a bit better then. What a great tool

[themos]

There seems to be a bug in that program, I am going to email the author. If you connect the Pipe diagnostic tool for the Focuser (and then select the simulator in that tool) you see, when you press the left button in Bahtinov Grabber, this:

Focuser Link: -> True (done)

Focuser Link: -> True (done)

Focuser IsMoving: False

Focuser Absolute: True

Focuser Position: 0

Focuser Move: -10 (initiated)

You are not supposed to ask for negative Moves in an absolute focuser.

[Tim]

What would make it perfect for me would be to have a sound file that beeped rapidly until focus was achieved and a flat tone could indicate that. It would save looking at the screen for those of use without electric focussers.

[Tim]

If you havent tried it, and if you have a filter wheel, a bahtinov mask is a great way to see exactly how your telescope brings the colours to focus, and how much difference there is between the reds and blues.

It showed to me that I cant really expect the best results using a OSC on a doublet for instance, as only one colour out of the three would be in perfect focus, but with a mono camera, the adjustment can be made between each colour very accurately.

edit: The above assumes parfocal filters, like the Baader CLRGBHaO3S2 set

[themos]

What would make it perfect for me would be to have a sound file that beeped rapidly until focus was achieved and a flat tone could indicate that. It would save looking at the screen for those of use without electric focussers.

Astrosnap Lite (edited) has that.

[themos]

Neil may put an update up, he's fixed the problem of sending -ve Move commands in Absolute mode.

I've been playing with his software and my homemade ASCOM focuser and it did work a few times. I have a problem, though, with image shift when I reverse direction, the mechanics of the focuser tube are atrocious (it's a Celestron starter scope). The image shift confuses the autofocus as the Bahtinov pattern moves off the capture area. So, more often than not, autofocus fails.

I'd really like to hear from other people who have tried this software if it works reliably for them and if they have any issues with image shift.

[Glider]

I use the software and it's fine by me, but I focus by hand only.

What would be really good is if it had a camera interface built in rather than the way it grabs a region of the desktop at the moment.

But apart from the wish list it's good.