NGC7822, my second full narrowband.

[emyliano2000]

I finally managed to capture everything I wanted for this target and as I have been advised, I stacked and calibrated in pixinsight. 

It is a mixture of 300 and 600sec subs shot with the QHY183M through a SW130pds and AT106.

Roughly 50x300sec and 40x600sec for each filter.

The Oiii filter is giving me these huge halos and not so very small stars which I'm finding hard to tame.

I will try to add a little of the Ha as luminance layer to see if I can make it better.

Emil

[Adreneline]

Very nice Emil.

1 hour ago, emyliano2000 said:

The Oiii filter is giving me these huge halos and not so very small stars which I'm finding hard to tame.

I have had exactly the same issue with my OIII filter (and my Blue filter). I've tried all manner of things to reduce the problem and at the moment my favoured (no doubt cheating) approach is to take the OIII (or Blue) image from PixInsight into Photoshop where I apply a star size reduction action from Annie's Astro Actions. I apply the action three or maybe four times and then take the resulting image (tif) back into PixInsight to combine with Ha and SII (or R and G). For me this method works but I am sure that others will have a better approach. There is no doubt a suitably complicated way of doing it in PI involving all manner of masks, etc. but AAA's are much easier and well worth the $15 or whatever I paid. (P.S. I am a big fan of PI believe it or not)

I'm not sure whether it is a short-coming of the OIII (or Blue) filters or a shortcoming in my optics (ED80/ZS71/Samyang 135mm) or a combination of both.

It worked very well on my most recent HOO iamge here:

HTH or gives you some ideas.

Adrian

[emyliano2000]

2 hours ago, Adreneline said:

take the OIII (or Blue) image from PixInsight into Photoshop where I apply a star size reduction action from Annie's Astro Actions.

At what point do you do this, right after stacking? I'm mostly using photoshop for my post processing and I probably have all the plugins and action packs possible including Annie's ones.

Do you process each filter before combining them?

Emil

[Adreneline]

1 minute ago, emyliano2000 said:

At what point do you do this, right after stacking?

Hi Emil,

I pre-process in APP (which I prefer to PI because I can do all the filters at once) and then take the resulting .fit files and StarAlign and DynamicCrop them in PI, followed by ABE (or DBE if I'm feeling super keen) and then lots small incremental HistogramStretch; I will typically do 10 or 12 small stretches each time making a small correction to the black point each time. 

I then take just the OIII (or Blue) as a 16 bit .tif into PS and apply AAA star size reducer action three or maybe four times.

I then take the resulting tif back into PI and combine in PixelMath or ChannelCombination.

Once combined and I'm happy I usually take the resulting image back into PS to make small level adjustments and align the histograms followed by as little noise reduction as I can get away with (using Dfine) and then finally a little bit of a lift to the colour, but nothing too much as I prefer the toned down subtle colours in my images.

HTH

Adrian

 

 

[emyliano2000]

I added the Ha as luminance and did a bit more work on it. Very pleased with how it came out.

Emil

[Adreneline]

Much prefer this version - nice one!

Adrian

[geordie85]

57 minutes ago, Adreneline said:

Much prefer this version - nice one!

Adrian

Ditto

[emyliano2000]

1 hour ago, Adreneline said:

Much prefer this version - nice one!

Adrian

 

14 minutes ago, geordie85 said:

Ditto

Me too 😁

[emyliano2000]

Ok, this is the final version. The previous one seemed a bit too dark.

Edited August 6, 2019 by emyliano2000