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The way to M31

Posted: Mon Aug 12, 2019 12:04 pm
by gaetano
Dear all,
the suggestions received on processing IC1805 were precious to me so I dare proposing another subject that is structurally different, in order to understand the subsequent differences in approaching it.
It is the hyper-well-known M31 coming from a noisy stack of few frames, I hope somebody will have little time to show us the way.
You can download it here https://www.dropbox.com/s/5h6x2jatl80l6wi/M31.fts?dl=0

Thank you in advance
Gaetano

Re: The way to M31

Posted: Tue Aug 13, 2019 8:58 am
by admin
Hi Gaetano,

You're acquiring nice data! :thumbsup:

Below a (very!) quick process in StarTools 1.5
M31(2).jpg
M31(2).jpg (594.66 KiB) Viewed 6632 times
Log as follows;

--- Auto Develop
To see what we got. We can see a red bias, noise, decent calibration except in the corners, oversampling.
--- Bin
To make use of oversampling for noise reduction.
Parameter [Scale] set to [(scale/noise reduction 35.38%)/(798.89%)/(+3.00 bits)]
--- Crop
Cropping away stacking artefacts and misalignment(?) artefacts.
Parameter [X1] set to [189 pixels]
Parameter [Y1] set to [44 pixels]
Parameter [X2] set to [1815 pixels (-319)]
Parameter [Y2] set to [1374 pixels (-52)]
Image size is 1626 x 1330
--- Wipe
Getting rid of light pollution / bias.
Parameter [Dark Anomaly Filter] set to [3 pixels]
--- Auto Develop
RoI over slice of M31
Parameter [Ignore Fine Detail <] set to [4.0 pixels]
Parameter [RoI X1] set to [671 pixels]
Parameter [RoI Y1] set to [525 pixels]
Parameter [RoI X2] set to [882 pixels (-744)]
Parameter [RoI Y2] set to [909 pixels (-421)]
--- HDR
Showing a little more detail in the core.
Tame preset.
--- Deconvolution
Tightens up things just a tiny bit.
Default settings.
--- Color
You're looking for a yellow/milky core (older stars) and bluer outer rim (younger stars).
Parameter [Green Bias Reduce] set to [1.18]
Parameter [Red Bias Reduce] set to [1.58]
Parameter [Cap Green] set to [To Yellow]
--- Wavelet De-Noise
Parameter [Filter Type] set to [Distance Weighted Outlier Rejection]
Parameter [Grain Size] set to [4.0 pixels]
--- Wavelet De-Noise
Parameter [Grain Dispersion] set to [4.0 pixels]
Parameter [Smoothness] set to [69 %]

Hope this helps!

Re: The way to M31

Posted: Sat Aug 17, 2019 9:04 am
by gaetano
Thank you so much, this helps a whole lot!

By the way, I see you worked this image with version 1.5, is this available for MacOS? If yes, I would be very happy to try it :thumbsup:

Thank you
Gaetano

Re: The way to M31

Posted: Sun Aug 18, 2019 1:46 am
by admin
1.5. (including Release Candidates) is indeed available for all platforms. PM sent!

Re: The way to M31

Posted: Mon Aug 19, 2019 6:04 pm
by Rkonrad
Here is my version Gaetano. The stars a are a little more prominent than I would prefer but time stopped me from doing a star removal step. I'm not totally convinced of the overall colour (max rgb under colour shows a good bit of red in the outer areas of the galaxy which seems unusual to me - so I did a bit of alteration). I also should have probably binned it down to Ivo's choice 35% but did 50 as I didn't want square stars at a deeper level. As a result there's more noise than I want. I found that "Contrast - compensate gamma" gave quite a bit of detail even beyond sharpening...
It's amazing how much of m31 comes out with little acquisition time!

Here is a link to it https://www.flickr.com/gp/rkonrad/x347gN

Sorry but I'm having major trouble accessing the log file with my medium slow computer and all the characters that make up the masks. Ivo - is there another way (perhaps in the 1.5 version) to access and post log file in my situation? My computer is good enough for processing but the log files take too long to load. I will try to post my process when I get past this point.

Cheers Richard

Re: The way to M31

Posted: Mon Aug 19, 2019 9:43 pm
by gaetano
Hello!
Thank you for taking time to process my acquisitions, it is definitely helpful for me to understand the many possibilities offered by StarTools.
Your answer popped up while I was actually spending some time on the very same image :D

Looking forward to see your log and compliments for the final result.

G

Re: The way to M31

Posted: Tue Aug 20, 2019 5:01 am
by admin
Nice processing Richard!
As for the logs, the issue is likely with the software you are using to view them.
Try something like Notepad++ to view them.

Re: The way to M31

Posted: Tue Aug 20, 2019 8:24 am
by happy-kat
With the log fine also turning off word wrap helps.

logfile

Posted: Tue Aug 20, 2019 2:37 pm
by Rkonrad
The logfile is 320 mg which is a lot of data for a text file. I'm using Linux Mint and use the default software "text editor". Notepad doesn't load anything (that's under WINE). I also tried Abiword though I gave up after about 20 min. It's interesting that others don't seem to have the same issue. I'm using an I3 processor with 24 g of ram.

Is there anyway of shortening the history of the log file so it doesn't retain so much data?

Richard

Re: The way to M31

Posted: Wed Aug 21, 2019 1:04 am
by admin
Ah, yes. Pluma or GEdit (same apps) freak out with long lines for some reason.
If you want to cut down the log file, you can do something like this a shell;

Code: Select all

tail -n200 StarTools.log > StarToolsCutDownLog.log
This outputs only the last 200 lines of the log and sticks it in a file called "StarToolsCutDownLog.log".