Newbie needs help with M31 data

[wedgef5]

I captured this data of M31 a few weeks ago, and I'm really struggling with it. I recognize that it has a lot of issues: noise, coma, light pollution, etc. I'm hopeful that StarTools can still salvage it.

Here are the particulars...

Subs:
60 x 30" Lights, unguided
20 x 30" Darks
20 Flats

Camera:
Unmodified Canon 450D at ISO 800

Scope:
6" f/5 Newt

Stacking was done in DSS with these pertinent settings...
No white balance
Bi-linear Bayer interpolation
Stacking mode: Kappa-Sigma Clipping
No Background Calibration

The output FTS from DSS can be found here: https://www.dropbox.com/s/vj9vvbirasqky ... 6.fts?dl=0

I've made a few attempts at processing it with ST, but I always end up with lots of noise left over. I've generally been following the workflow of: Load, Bin, AutoDev, Crop, Wipe, AutoDev...and at this point I still have lots of noise, and I think it should be looking much better than it is. I think I am just not familiar with ST yet.

Any helpful advice would be greatly appreciated!

Matt

[Cheman]

Hi Matt
Here is what I came up with processing your data and the log file of my processing. It would be interesting to see what you came up with on your tries.
Che

Autosave006.jpg (127.17 KiB) Viewed 8493 times

StarTools 1.4.297
Fri Oct 23 19:50:39 2015
-----------------------------------------------------------
File loaded [C:\Users\Che\Desktop\Autosave006.fts].
---
--- Crop
Parameter [X1] set to [23 pixels]
Parameter [Y1] set to [26 pixels]
Parameter [X2] set to [2106 pixels (-39)]
Parameter [Y2] set to [1374 pixels (-54)]
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [UNKNOWN] set to [Yes]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Drop Off Point] set to [100 %]
Parameter [Corner Aggressiveness] set to [100 %]
Parameter [Aggressiveness] set to [75 %]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [91.45 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
--- Contrast
Parameter [Expose Dark Areas] set to [No]
Parameter [Compensate Gamma] set to [No]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Aggressiveness] set to [59 %]
Parameter [Dark Anomaly Headroom] set to [15 %]
--- Deconvolution
Parameter [Image Type] set to [Deep Space]
Parameter [Mask Behavior] set to [De-ring Mask Gaps, Hide Result]
Parameter [Radius] set to [2.6 pixels]
Parameter [Iterations] set to [6]
Parameter [Regularization] set to [1.00 (optimal noise and detail)]
Parameter [Mask Fuzz] set to [8.0 pixels]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [91.85 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
--- Color
Parameter [Cap Green] set to [To Yellow]
Parameter [Bias Slider Mode] set to [Sliders Reduce Color Bias]
Parameter [Style] set to [Artistic, Detail Aware]
Parameter [LRGB Method Emulation] set to [50/50 Layering, CIELab Luminance Retention]
Parameter [Dark Saturation] set to [2.00]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [314 %]
Parameter [Blue Bias Reduce] set to [1.00]
Parameter [Green Bias Reduce] set to [1.28]
Parameter [Red Bias Reduce] set to [1.57]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [92.39 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
--- Wavelet De-Noise
Parameter [Scale 1] set to [90 %]
Parameter [Scale 2] set to [90 %]
Parameter [Scale 3] set to [90 %]
Parameter [Scale 4] set to [90 %]
Parameter [Scale 5] set to [0 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Scale Correlation] set to [3]
Parameter [Color Detail Loss] set to [12 %]
Parameter [Brightness Detail Loss] set to [12 %]
Parameter [Grain Size] set to [6.0 pixels]
Parameter [Read Noise Compensation] set to [Off]
Parameter [Smoothness] set to [75 %]
File saved [C:\Users\Che\Desktop\Autosave006.jpg].

[wedgef5]

Thanks Che! That looks way better than anything I had gotten so far. I can't share what I had done, as I was trying out ST in demo mode. I just sent payment to Ivo today, so I'll be a "real" user soon!

I'm curious how you determined how far to crop. Did you do an AutoDev first? It wasn't real clear to me how far I needed to go on a couple of the sides. Also, have you had much experience with the Lens module? I tried to straighten out the coma in the image, but I wasn't having a lot of success.

Matt

[Cheman]

Hi Matt
on your image, I just lopped off a bit at random If taking more care I would first autodev and see what was needed. Many times it will be very obvious, other times more subtle. Then I would bin and wipe( with with temp auto develop enabled to be able to see how it does. this is where I sometimes find that I might need to crop more if I get strange or uneven results). I have never used the lens module so cant give any advise there. I'm sure you'll enjoy using StarTools
Che

[wedgef5]

So, I haven't been able to get any better results than Che's so far. I'm still trying, though. I am wondering, however, why is my background so red? It doesn't look like classic light pollution (the yellow-brown cast). I'm wondering if it is an issue in the acquisition, in the stacking or something else.

Thanks for any input.

Matt

[Cheman]

Hi Matt
Is the background red before or after wipe?? mine are usually red/orangeish and yellow before wipe, viewing using Autodev see attached Stephens Quintet before wipe.
Che

prewipe (Medium).jpg (118.58 KiB) Viewed 8455 times

[wedgef5]

Here's what it looks like before the wipe...just load and auto-dev

prewipe.jpg (106.12 KiB) Viewed 8446 times

And after a crop, wipe and auto-dev. There is some decent detail in there that I'd like to tease out.

afterwipe.jpg (213.02 KiB) Viewed 8446 times

[Cheman]

after wipe, redo global stretch using develop, not autodev. Keep pressing "home in" until it gets to where you like it and see if that helps. Thats what works for me.
Che

[wedgef5]

I was leaning toward auto-dev based on Ivo's recommendation in the Modules documentation...

"AutoDev has a lot of smarts behind it - some heavy analysis is going on of the ROI so that it can
find the optimum histogram transformation curve. Develop, in comparison, is rather 'dumb' and
mimics photographic film development, which doesn't actually take into account what is in the
image."

I tried yet again, and got a decent result. Auto-dev did a much better job when I gave it an ROI focused on the galaxy core and some of the adjacent dust lanes. I was even able to mostly correct the bad coma caused by my f/5 Newt.

M31-ST-Try2.jpg (101.72 KiB) Viewed 8436 times

Workflow...
File loaded [C:\Users\Matt\Pictures\Astro\M31\Autosave006.fts].
---
--- Auto Develop
Parameter [Ignore Fine Detail <] set to [Off]
Parameter [Outside ROI Influence] set to [15 %]
--- Lens
Parameter [UNKNOWN] set to [On]
Parameter [Curvature Red] set to [148.09 %]
Parameter [Curvature Blue] set to [148.09 %]
Parameter [Center X] set to [212 pixels]
Parameter [Center Y] set to [-141 pixels]
Parameter [Red Shift X] set to [0.0 pixels]
Parameter [Red Shift Y] set to [0.0 pixels]
Parameter [Blue Shift X] set to [0.0 pixels]
Parameter [Blue Shift Y] set to [0.0 pixels]
Parameter [Curvature Linked] set to [148.09 %]
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
--- Crop
Parameter [X1] set to [5 pixels]
Parameter [Y1] set to [0 pixels]
Parameter [X2] set to [832 pixels (-0)]
Parameter [Y2] set to [537 pixels (-5)]
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [UNKNOWN] set to [Yes]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [3 pixels]
Parameter [Drop Off Point] set to [100 %]
Parameter [Corner Aggressiveness] set to [100 %]
Parameter [Aggressiveness] set to [75 %]
--- Auto Develop
Parameter [Ignore Fine Detail <] set to [Off]
Parameter [Outside ROI Influence] set to [15 %]
--- Deconvolution
Parameter [Image Type] set to [Deep Space]
Parameter [Mask Behavior] set to [De-ring Mask Gaps, Hide Result]
Parameter [Radius] set to [2.5 pixels]
Parameter [Iterations] set to [6]
Parameter [Regularization] set to [1.40 (smoother, less detail)]
Parameter [Mask Fuzz] set to [8.0 pixels]
--- Wavelet Sharpen
Parameter [Intelligent Enhance] set to [Yes]
Parameter [Scale 1] set to [100 %]
Parameter [Scale 2] set to [100 %]
Parameter [Scale 3] set to [100 %]
Parameter [Scale 4] set to [100 %]
Parameter [Scale 5] set to [100 %]
Parameter [Mask Fuzz] set to [8.0 pixels]
Parameter [Amount] set to [100 %]
Parameter [Small Detail Bias] set to [75 %]
--- Contrast
Parameter [Expose Dark Areas] set to [No]
Parameter [Compensate Gamma] set to [Yes]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [3 pixels]
Parameter [Aggressiveness] set to [75 %]
Parameter [Dark Anomaly Headroom] set to [15 %]
--- Wavelet Sharpen
Parameter [Intelligent Enhance] set to [Yes]
Parameter [Scale 1] set to [100 %]
Parameter [Scale 2] set to [100 %]
Parameter [Scale 3] set to [100 %]
Parameter [Scale 4] set to [100 %]
Parameter [Scale 5] set to [100 %]
Parameter [Mask Fuzz] set to [8.0 pixels]
Parameter [Amount] set to [100 %]
Parameter [Small Detail Bias] set to [85 %]
Undo.
--- Color
Parameter [Cap Green] set to [To Yellow]
Parameter [Bias Slider Mode] set to [Sliders Reduce Color Bias]
Parameter [Style] set to [Artistic, Detail Aware]
Parameter [LRGB Method Emulation] set to [Straight CIELab Luminance Retention]
Parameter [Dark Saturation] set to [2.00]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [239 %]
Parameter [Blue Bias Reduce] set to [1.23]
Parameter [Green Bias Reduce] set to [1.13]
Parameter [Red Bias Reduce] set to [1.70]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- Wavelet De-Noise
Parameter [Scale 1] set to [90 %]
Parameter [Scale 2] set to [90 %]
Parameter [Scale 3] set to [90 %]
Parameter [Scale 4] set to [90 %]
Parameter [Scale 5] set to [0 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Scale Correlation] set to [3]
Parameter [Color Detail Loss] set to [12 %]
Parameter [Brightness Detail Loss] set to [12 %]
Parameter [Grain Size] set to [5.0 pixels]
Parameter [Read Noise Compensation] set to [Off]
Parameter [Smoothness] set to [65 %]
File saved [C:\Users\Matt\Pictures\Astro\M31\M31-ST-Try2.jpg].