For those who have never tried a Bahtinov Mask

[Euan]

I tried going down the auto-focus route and wasted far too many nights toiling with Focusmax. I then thought I would try a Bahtinov mask from eBay

..what a difference!

I can get focus in just a few seconds now, it's a doddle even when changing filters and re-focusing. I wished I hadn't wasted so many clear nights and got one ages ago. Even if you don't have live preview and have an older DSLR I can image it would make a huge difference

A big thumbs up from me

[Catanonia]

Good ain't they

[RobH]

They are great....very accurate.

I have a whole bunch of them for different scopes/FL's.

However, I now have robofocus fitted to both my 6 inch and 80mm scopes, and use focusmax.

This is a fraction more accurate, and almost as quick.

What problems were you having with FM?

It works fine for me. Maybe I can be of assistance.

Cheers

Rob

[sgazer]

I second that, the single most useful thing ever (more or less). I even made one for a camera lens that was only 50mm diameter and it works a treat!

[themos]

I understand that focusmax needs an ASCOM focuser (I am building one myself) but is it true that it also needs Maxim for image acquisition (or some other commercial software costing mucho dinares)?

[RobH]

Yes, you do need something like Maxim.

With Robofocus alone though, you don't, and the combination of robofocus and a Bahtinov mask is a joy to use

Cheers

Rob

[Psychobilly]

Try using the Bahtinov Grabber app...

Apart from the fact that it doesnt remember the FL and aperture settings its great for telling you when your in precise focus...

And can control a focuser as well...

Peter....

[red dwalf]

i made one from a cut out from the net, take abit of effort to cut out but they work very well, very, very easy to pick up and use, as you say focus in seconds

[MartinB]

I use robofocus and focusmax on my FSQ and there is nothing to touch it. Also have used it with my LX200 but for on changing my laptop I've tried to set it up again. I just can't get it to find focus. So I've also resorted to a bahtinov mask and it is excellent. Great with an SCT because you can visually see when you've hit optimum focus without going back and forth which is a nightmare with SCTs and mirror shift.

[Euan]

Rob, it turned out to be more of a hardware limitation than the fault of Focusmax. With the DC motor Moonlites and a controller (tried Lazyfocus & FCUSB), the focusing was really unreliable. The Lazyfocus wouldn't move the motor AT ALL, and the FCUSB started to give up when I added a filter wheel onto my imaging train.

The way to do it properlly is to use the stepper motor for the Moonlites of course but when it's £300+ versus a £8.99 mask guess what wins

[RobH]

The way to do it properlly is to use the stepper motor for the Moonlites of course but when it's £300+ versus a £8.99 mask guess what wins

No, you can't argue with that

[Psychobilly]

Bahtinov Grabber app and some other interesting stuff can be downloaded from here...

Astro Software Niels Noordhoek’s weblog

V10 remembers the settings as well...

WARNINg - dont click autofocus if you havent got an ASCOM compliant focusser connected as this will generate an exception which cannot be recovered from... you cant even toggle the autofocus setting to off when you restart the program... fortunately I found this out on my desktop pc not the obs one....

Peter...

[themos]

Bahtinov Grabber sounds great! It motivates me to finish writing the ASCOM driver for my home-made focuser.

[LukeSkywatcher]

Here's a site where you can generate your own mask and print it off.

astrojargon - Bahtinov Focusing Mask Generator: Overview