Do you have auto stretch turned on in SGP?
Yes, that’s it.
Thanks,
Jared
there are some programs that have an assisted focus with the bathinov mask. Maybe it could a new function you can add in your future release! 
1 Like
We have considered integrating Bahtinov Grabber into SGPro in the past. Of course the original author (the late Niels Noordhoek) created and distributed this software for free. If we ever integrate in this way, it will be part of SGLite so we can continue to propagate the software according to the author’s original intent.
Moving to feature requests.
No auto stretch when I’m using live view, too much noise. Don’t need it for single shots with the mask, those are well resolved.
News about the Bathinov Grabber integration in SGP Pro?
We have not yet decided if we are going to do this. If we did, it would be in 2.5.
I hope you decide to support. A lot of people use bathinov mask for focus. It would be awesome! good work!
I’m also looking forward to this feature.
Not all of us uses auto focusing and this makes me much easier to focus than using SGP and he grabber separately.
2 Likes
I agree with donghun. I use several scopes and only 2 have autofocus options.
So a manual aid via a grabber like feature would be of great help.
Thanks
Robert
Another vote here for an integrated Bahtinov Grabber.
Regards
John
1 Like
Agree, it will be an good focusing option.
I’d also love to see this incorporated into Sgp - would be a great feature
One thing I’ve seen with all these focusing methods is the need to get fairly close to focus before they work. This applies with or without a Bahtinov mask.
What I see in the image when I’m a long way away from focus is a collection of circles or doughnuts. I make a focus change and see what happens. If the circles get bigger I’ve gone the wrong way. If they get smaller I’m going the right way. I continue making focus adjustments until I’m close enough for auto focus to work.
I wonder if this could be automated:
- Collect an image
- Detect circles (the Circular Hough Transform maybe)
- Get the average circle radius.
- Move the focuser.
- Collect an image
- Detect circles and determine their radius
- Use the change in circle radius and focuser movement to find an
approximate best focus. - Move there.
- Do fine focus.
I’m not sure how practical this would be and there’s a lot of development and testing needed but it could be very useful, especially if it could be used to avoid the problem of spurious low HFR values with obstructed scopes.
Chris
2 Likes
Another vote here for an integrated Bahtinov Grabber (or similar, of course)
I’ve got two scopes, but not enough money for two autofocus… 
Regards from Spain.
My vote for integrating some sort of Bahitnov Grabber feature !!
-Kai
Hello all,
What Chris is suggesting sounds like a great Idea. One thing to bare in mind though, when SGP does an auto focus run and successfully finds best focus position for the focuser it could ‘LOG’ the focusers position along with current temperature when it ran. It could add to the log every time it finds a temp which is missing from the Log file thus building up a database of starting positions based on temp. This database will be unique to everyone’s individual setups.
I myself when finishing an imaging session always crank the focuser tube all the way in as im sure most people do so when setting up, my focuser tube always begins at position zero and have to go through the annoying process of finding focus first. At the press of a button, SGP could consult this ‘LOG File’ after establishing what the current temperature is and find a focuser position based on that temp from a previously successful focusing run at that temp and auto push the focuser tube out to that position to start. Theoretically this position will be very close to focus anyway. Either SGP could run auto focus from here or run a little sequence like Chris has suggested to do any fine tune before a sequence proceeds or autofocus is invoked.
Obviously this isn’t going to do a huge amount for people who don’t have an autofocusing system installed but it would enhance automation which is what SGP is all about. I know the documentation states that SGP’s purpose is to maintain focus throughout a session but a small feature like this could also automate the initial focus stage too.
Just a thought !
Paul
SGP already allows you to setup a start position for focus, it’s just not temperature based. Please see here in the “Filter Setup Dialog”:
http://mainsequencesoftware.com/Content/SGPHelp/FilterWheels.html
Focus pt: Used to specify a starting point as well as to specify the offsets for adjusting focus on filter change when using an absolute focuser when Auto adjust focus per filter is enabled. Because of the way in which “focus on filter” works it is recommended that you set the focus position of your filters near the same ambient temperature.
Thanks,
Jared
I would really like to see the initial focus position adjusted for temperature. This can be easily incorporated by getting two numbers from the user: 1) slope of focus least square fit line 2) intercept of the line. These two numbers define precisely the best focus position as a function of temperature. This would allow the maintenance of an excellent focus position completely automated for a long period of time. Auto focusing would not even be required, except perhaps from time to time to confirm that the best fit line is optimum.
If additionally, a maximum deviation of the focus position from this calculated value could be given, then I would have no reservations about running the autofocus routine on some regular interval during each night’s session. The reason I do not do so now is that, although the new auto-focus routine works wonderfully well, most of the time, it sometimes fails. When it fails, it leaves my focus position badly out of focus and that whole stretch of imaging time is toast. There are various reasons why it might fail, perhaps a brief cloud or wind gusts come along. My RC12 is particularly prone to auto-focus failures, so I never ever run the auto-focus unless I am attending it. It works so much better to just let the temperature compensation just do its thing.
This would in no way change anything for those folks who are very happy with the way it is running now. It would just be a new optional feature that could be turned on.
You can use temperature compensation which already exists in SGP. The only piece missing is getting you to the first focus position.
Thanks,
Jared
Yes, quite so. That is my standard way of operating now, on all my scopes. But I have to initiate it to a good focus position when the evening starts. I can’t start an automated process at 10 in the morning or 6 pm and let it completely run the night’s imaging session. I don’t know what the temp will be at 9:45pm when it starts taking images to be able to set the correct focuser position. I have to be at my computer at 9:45pm and do this manually.