ASIAIR Narrowband Autofocus Exposure Times

SB (Chris) · #1 17-12-2021, 07:44 AM

Hi All,
I have no problem using ASIAIR autofocus with broadband, however I find Narrowband more difficult. I am using Antlia 3.5nm filters with ASI183mm.

Focussing on targets like NGC2070 is particularly difficult. Moving to a nearby star field to focus might be fine for the first filter and then slewing to target, but this would be impractical for each filter.

What exposure lengths would you recommend for ASIAIR autofocus using narrowband filters and at what BIN setting?

Feedback appreciated.

Best.

SB

pmrid (Peter) · #2 17-12-2021, 08:18 AM

I use a ASI1600MM with 5nm Astrodon NB filters. I use a gain setting of 200 generally and 5 second subs in autofocus. So far, I have had no problems.

SB (Chris) · #3 17-12-2021, 08:29 AM

Thanks Peter
What BIN setting do you use? I’ve been using BIN 4.

SB

rustigsmed (Russell) · #4 17-12-2021, 08:45 AM

Quote:

Originally Posted by SB

Thanks Peter
What BIN setting do you use? I’ve been using BIN 4.

SB

i think you get better results in any autofocus program sequence by not binning and upping the gain and exposure time. I had trouble when binning in other programs.

pmrid (Peter) · #5 17-12-2021, 04:54 PM

Quote:

Originally Posted by SB

Thanks Peter
What BIN setting do you use? I’ve been using BIN 4.

SB

Bin 1. Never bothered with more.