Obtaining Autofocus Log & Focus Settings


#1

I’ve searched on the forums here and found one thread with regards to obtaining Sequence Log information - specifically with regards to the Autofocus tool. I was thinking about running Flats for my most recent imaging (which I ran differently - I had it do Autofocus between Filter changes). The results of that run were amazing, so I’m thinking that despite my filters being parafocal, a little fine tweaking is still best to optimize results. Before I was just Autofocus’ing the Lum filter only. So rather than spend 5-10 minutes doing a focus on filter, I wanted to use the Absolute values.

From my understanding, if I can pull up the log files from this last sequence, I can find whatever the generated focus value for the Lum filter was (ex. 25430) and then look at the other filters (ex. Red: 25330, Blue: 26430, Green: 25230, etc) and then use these absolute values in the Filter Focus settings instead - So for Lum I’d leave it to Autofocus, but for rest it would be (from the examples above): Red: -100, Blue: +1000, Green: -200, etc. So it would Auto-focus the Lum filter, then auto-adjust everything else after that. Since the filters should be linear given any temperature adjustments, the values should align perfectly. If I’m understanding that functionality correctly?

The main question of this thread, however, is how do I find/view those values from the last sequence run? I know there is a log file of it (from threads talking about), but where exactly is that file located? Can I view it somehow directly in SGP? Looks like another clear night tonight, so would love to get it all updated and ready before it gets dark to test it out tonight! Thanks to anyone who can help point me in the right direction and confirm (or correct) my understanding of the Focus setting!


#2

You would use the absolute values (26430, 25230, etc), not the relative (-100, +100, etc). SGP will convert these property to offsets internally but using the absolute values also gives you a “starting point” to go to as well. You’ll want to use the “Adjust Focus Per Filter” option that will apply these values.

No, but if you go to the “Help” menu there are options there to open the current log, or open the folder where all the logs are (this is likely what you want).

Thanks,
Jared


#3

Thanks for the info Jared!

Managed to get a focus set done last night and the absolute values loaded into the filter focus points. Also enabled the Adjust Focus Per Filter setting and it looks good.

The last question I have is in regards to Sequences. I was able to run the Lum filter manually (for the Auto Focus) and then “Set Focus Position for Filter”. It then had a checkbox I had to select to auto-adjust all other filters by +/- X. If I enable the ‘Run Autofocus at the start of sequence’ or any of the other sequence automated focus parameters (Every X frames or for Temp Compensation, etc), will it automatically update all the other filters during the sequence? I didn’t see an option anywhere to have it do the adjustment to the other filters automatically and since I had to manually check the box to Adjust the filters, wondering if the sequence automation just does it without asking.

Thanks!


#4

No, and it doesn’t need to. Those values need to be relative to one another at a given temperature…so you want to set them all when seeing and temperature are pretty stable. From there you use the “auto adjust focus per filter” option and SGP will apply your offsets. The absolute number is just a rough starting point. So if you ever zeroed your focuser you can click “Focus for Lum” and it will quickly move to that position. You likely won’t be in perfect focus there…but you’ll be in the ballpark.

Let’s say you setup your filters initially like:
Lum - 1000
Red - 1100
Green - 900

You’re on lum and you’ve focused and you’re currently at 1050. You clip to Red and SGP will take the (Red - Lum = 100) and apply this offset. so Now you’re on red and at 1150. The night goes on and cools some, you run auto focus and you’re now at 1120 on your Red filter. You switch to Green and SGP takes (Red - Green = -200) and moves to 920 with the Green filter.

Hope that makes sense.
Thanks,
Jared


www.mainsequencesoftware.com