Okay let me see if I can ask this and get to the point quickly and not reinvent past posts.
I’m trying to figure out how to get my auto focus to work with offsets and my astrodon filters.
What I think I understand about Auto Focus…
- I know you designate your “Focus Point” in your filter setup menu
- I understand all the boxes and what needs to go in them in the “Auto focus Settings Dialog” box
- I understand how to start looping an exposure to get the HFR 4 to 5 times higher than the original number and then use the formula of subtracting your in-focus numbers to get the step size for the particular filter that you are using. All done through your “Focus Control”
- I understand that when you have “Auto adjust focus per filter” checked that it takes into consideration that the focus point will change from night to night based on variables like the temp outside etc.
What I am not understanding is how to pull all this together. I think when I am reading what I wrote above that I might be combining a few different scenarios that don’t necessarily go together.
I think I understand that using the formula listed above will give me the step size for each of my astrodon filters but after reading various posts it seems that using that formula does not necessarily give me the actual step size that will be used all the time in my auto focus sequence.
How do I determine what that step size should be?
For Example:
If I get the focus number for my Lum filter, and then figure out the focus number for my Ha filter, I’m guessing that I just subtract/add it to the Lum’s number to get the number of steps between the two filters, and then use that number to tell SGP to add/subtract from the Lum’s focus point to get the focus point for the Ha? And then do the same for the other filters. Would that number then be considered the Ha’s “Focus Point?” And is that the number I should enter into the “Focus Point” line item in the “Define Filters” box?
If that’s the case then it stands to reason that no mater what the focus number ends up being on Lum for any given night it will then add/subtract that predetermined number for Ha, set it there, and then run an auto focus to get it dialed in exactly? Correct?
All this seems to make sense when you look at using that formula to get the step size if you were using auto focus for each filter individually but I’m missing something here on the final step size.
In the end will there be one number for step size in the “Auto Focus Settings Dialog” box and if so how do I determine what that number will be.
Sorry if this was convoluted but I’m trying to figure out what to say as I write it.
Thanks Sean