Processing star clusters

[celeron787]

About 30mins integration time of M46 and M47 star clusters in a B8 zone.
I know that I would benefit from longer intergration time but I would like to see if this set of data could be processed better.
Any tips to push back the background noise a little bit more but retaining the same amount of stars? Super Structure default does the job quite well but gives me a mottled background.

Stacked file: https://www.dropbox.com/s/wb5t6wb0yaj1buh/47.FTS?dl=0

Screenshot 2021-02-06 230833.jpg (458.69 KiB) Viewed 1793 times

Sony A6000
William Optics RedCat 51 Petzval APO
Sky-Watcher Star Adventurer
Tripod

Bortle 8
ISO800
Light frames - 87 x 20secs (manually dithered in RA and DEC)
Dark Frames - 30 x 20secs
Flat Frames - 30
Bias Frames - 50

Deep Sky Stacker
StarTools - Autodev, Crop, Wipe, Super Structure (brighten), Decon, Color, Denoise
Lightroom - Vibrance, Saturation brush on planetary nebula

[admin]

The Super Structure module is indeed the best tool for this job. I wasn't able to replicate the mottled background(?), but when using the Super Structure module, make sure to roughly match the field of view to the Airy Disk. From the docs;

The 'Airy Disk Radius' parameter sets the radius of the Airy disk point spread function (PSF) that is used to diffract the light. Smaller values are generally more suited to wide fields, whereas larger values are generally best for narrow fields. This is so that the PSF mimics the diffraction pattern of the original optical train. 'Incorrect' values may make the image look fuzzier than need be (in the case of wide fields), or may define super structures less well (in the case of narrow fields).

PS The manual dithering is working wonders!

[celeron787]

The Super Structure module is indeed the best tool for this job. I wasn't able to replicate the mottled background(?), but when using the Super Structure module, make sure to roughly match the field of view to the Airy Disk. From the docs;

The 'Airy Disk Radius' parameter sets the radius of the Airy disk point spread function (PSF) that is used to diffract the light. Smaller values are generally more suited to wide fields, whereas larger values are generally best for narrow fields. This is so that the PSF mimics the diffraction pattern of the original optical train. 'Incorrect' values may make the image look fuzzier than need be (in the case of wide fields), or may define super structures less well (in the case of narrow fields).

PS The manual dithering is working wonders!

Thanks Ivo! I went with a default Super Structure but at lower strength which I'm happy with. I then run Super Structure again with Brighten preset. Is it advisable to run the same module multiple times?

Would you mind sharing your processing log for this file?

[admin]

Thanks Ivo! I went with a default Super Structure but at lower strength which I'm happy with. I then run Super Structure again with Brighten preset. Is it advisable to run the same module multiple times?

Not typically (the ST philosophy is "do it once, do it right"), however the Super Structure module can do multiple useful things. I will actually be implementing a "chain" button, so you can use the output from one setting as the input for another.

Would you mind sharing your processing log for this file?

I had a quick play with it, but I just used a minimal flow.

AutoDev to see what we got, Bin 50%, Crop, Wipe with Uncalibrated 1 preset (probably overkill but usually quite safe when dealing with extreme widefields), AutoDev with RoI over cluster and reduced Shadow Linearity, Decon w/default settings, Color w/Cap Green set to 100%, Super Structure Isolate preset w/Airy Disk Radius set to 3%, ran it again and used the Brighten preset (again w/Airy Disk Radius set to 3%), switch Tracking off, default noise reduction.

That yields something like this;

47.jpg (472.81 KiB) Viewed 1774 times

This all really depends on your taste of course.