Hi!

I'm not really sure how the scheduler handles different filters, so I ask here. I am setting up a RGB job for the night. That is: a batch of R images, then G images, then B images. My question is, how focusing is handled. So far, it seems to me that the focuser does not necessarily shift to the same filter as what is used in the Capture module. So how do I manage that there are filter shifts and a certain degree of focus shift between these filters (yes, they probably should be parfocal, but are they really,.....)? Does the focuser really shift filters when running with scheduler? Or is there a way to make it? OR should this be handled by focusing with Lum and then setting offsets?

Magnus

I will be trying this out tomorrow, but under the focuser module there is a filter checkbox that leads to a menu, where you can set autofocus on a per filter basis. Unclear whether this means focusing away to a filter or focusing to a filter. Anyhow going to try it all tomorrow, weather permitting.

I'll report back

Oh and a little word of warning, those filter autofocus settings seem to still apply when you try to take calibration frames, so maybe disable them and restart kstars if you do your calibration frames after your session.

I do this all the time. What I do is:

• Set up the scheduler with a sequence job that has say: 8 4-minute Red, 8 4-minute Green, 8 4-minute Blue, 8 4-minute Red, 8 4-minute Green, 8 4-minute Blue, 8 4-minute Red, 8 4-minute Green, 8 4-minute Blue, ...
  That is, about half-hour per filter.
• In the capture tab, I fill out the filter settings table (button just to the left of the '+' on the top row of buttons) with focus offsets for each filter and make sure the auto-focus is checked for all filters where I want focusing done (usually all of them).
• Refocus every ___ seconds is unchecked.
• Autofocus needs to be set up the way you want it in the focus tab.

Then, whenever it changes filters, it autofocuses, which for me would be about every half hour. This may be overkill, and you can change your sequence job accordingly.

This works pretty reliably for me, but, of course, you should check it while it's running the first few times to make sure you set it up properly.

Also, if you run the way I've described, the filter setting in the autofocus tab is ignored when autofocusing-on-filter-change is happening.

Hi!

Great, thanks! Which filters do you then use for focusing, that is, have you set "lock filter" as well, or do you focus with Red when capturing Red and so on? (which would eliminate the off-set, right?)

Actually, I have unchecked the "force autofocus" (or what it is called, don't have it here now) in the focus off-set window, because I experienced some disturbing loops with the alignment module - where alignment changed filter to Lum to align, then that forced autofocus and in some strange way, I was sort of locked into a situation where it spent like 90 % of the time focusing.... But as I take it, that is not the case for you - so must have been some other thing happening there. I will try your routine next time the clouds part!!

Best,

Magnus

Magnus,

There definitely used to be issues with the force autofocus checkbox. I believe I fixed most of that in the code in the past several months.
Not promising it's perfect, but I've been using it each imaging session for the last several months and things have worked well for me. All these changes are in the recent releases. For example,I made a change to the code that prevented the alignment tab from autofocusing when it changed filters for just the reasons you mentioned.

I think you misunderstand how it works. When the capture module, and ONLY the capture module, changes filters (e.g. when going from one sequence to another), it autofocuses using the filter that the capture module wants to use. The filter set in the focus tab is ignored. The filter setting in the focus tab is used when auto focus is called for other reasons, for instance: at scheduler start up if you have focus checked, or if you're just in the focus tab and you click the autofocus button.

So, I'd recommend checking those force autofocus checkboxes for your situation.

If you find issues with the way this works, please post here and please add a debug log where most things I've been debug-logged.

I just noticed your question about "lock filter". I've never use that, that is I don't have it checked, and in fact I hadn't noticed that before and don't know what it does (though, of course I could guess).

Another amendment is that, on the two focus settings at the bottom of the capture tab, "Auto focus if HFR > __" and "Refocus every __", I have both unchecked, and I'd guess that those two would use the filter set in the autofocus tab, but honestly I'm not sure.