Narrow Band Question - SHO Balance - Forums

Topic starter

Sep 4, 2021

I’m just getting started and chose Sh 2-129 as the target due to favorable positioning.

There were numerous equipment issues so little useful data was obtained.

One thing I did notice was a good signal with the S and H filters, very little with the O filter.

My thinking was to go back to this object and try SHLRGB.

Is it ok to skip the O and create a color composite?

Michael Feldberg

Sep 4, 2021

Hi Jeff,

OIII is usually the weakest signal. As far as my limited experience (6 months) goes.
The images I’ve seen from SH2-129 so far, I’d guess you’ll need at least 15h OIII data to see the squid.
I don’t know if the SHLRGB approach would work on this target but I wouldn’t bet on it.

Bob Rucker

Sep 4, 2021

I recently imaged SH2-129 and used 18.5 hours for the Oiii channel. To be honest, even this was not really enough time and I had to get really creative with my processing to get it to show.

APP was used for stacking, light pollution removal and other basic processing on each channel. I then used the star removal tool in APP so that I had starless Ha and Oiii channels. The separate starless images were then cleaned up in Photoshop to remove star remnants and further processed. For the Oiii channel I used some rather creative heavy nonlinear stretching to to pull out detail.

I then used the HOO RGB combine tool in APP to create a color starless version along with a color HOO version with stars. Photoshop was then used to blend the starless version with stars along with some final tweaks for noise reduction, color balance, etc. I don't think the SHLRGB approach will substitute for Oiii. This is the most difficult target I've ever attempted and it put my mediocre processing skills to the ultimate test.

Gary Seven

Topic starter

Sep 5, 2021

Thanks guys. Good to know what I was seeing (OIII being a weak player here) was real.

Maybe I just go HLRGB. Or try a different target!