M42 and M31question

Questions and answers about processing in StarTools and how to accomplish certain tasks.
torsinadoc
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Joined: Sat Oct 05, 2013 2:58 pm

M42 and M31question

Post by torsinadoc »

finally hooked up to my scope (ES102) with non modified DSLR

As it was not guided, I have only 15 sec duration images (i think 80 or so) with darks, bias and flats. here is my first attempt. Not really sure what I am doing here. This is a screen shot but once it get the pass key to unlock the program I will save the file. Thoughts? Seems a little blurred. If i play with the file in PI I can get more contrast and color but i think if can get better results with star tools given my current level of understanding processing. Not sure what to expect given the likely poor quality. I can upload the master .fit if someone wants to show me what it should look like

M31 is not a good quality. PI wouldn't even stack it. Used DSS. It is blue likely from the CLS filter. When I tried to work on it using the M101 tutorial on youtube it just got worse. As there any hope or should I just trash it? My guide scope should arrive this week :obscene-drinkingcheers:
Attachments
M31 NOT PROCESSED
M31 NOT PROCESSED
Screen Shot 2013-12-01 at 11.53.01 AM.jpg (492.55 KiB) Viewed 9393 times
M42-star
M42-star
Screen Shot 2013-12-01 at 11.10.22 AM.jpg (417.97 KiB) Viewed 9393 times
torsinadoc
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Re: M42 and M31question

Post by torsinadoc »

here is my PI processing

Image
torsinadoc
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Re: M42 and M31question

Post by torsinadoc »

here is the debayered, not white balanced .fit file if anyone wants to take a stab at it. i cropped it after preprocessing

https://www.opendrive.com/folders?OF82ODE0NzQ4XzhBbmVz
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Re: M42 and M31question

Post by admin »

torsinadoc wrote:finally hooked up to my scope (ES102) with non modified DSLR

As it was not guided, I have only 15 sec duration images (i think 80 or so) with darks, bias and flats. here is my first attempt. Not really sure what I am doing here. This is a screen shot but once it get the pass key to unlock the program I will save the file. Thoughts? Seems a little blurred. If i play with the file in PI I can get more contrast and color but i think if can get better results with star tools given my current level of understanding processing. Not sure what to expect given the likely poor quality. I can upload the master .fit if someone wants to show me what it should look like
You actually did a very nice job in PI (but I'm sure ST can do better ;) ) Very good for 15 secs unguided. It looks nice and smooth too. Absolutely nothing to be ashamed about. It does suffer from the progressive desaturation problem (the core is rich in green OIII, it's not white, star color is not apparent) most PI images suffer from, but that's a different story.
I would love to have a play with the data! :thumbsup:
The last two YouTube (M8 and M33) tutorials are probably better suited to your data, while using the latest beta is highly recommended (so much easier & better results!).
M31 is not a good quality. PI wouldn't even stack it. Used DSS. It is blue likely from the CLS filter.
Yes a CLS (or any sort of LP filter) will make color balancing tricky (true color balance will never be recoverable is you've irrevocably rejected part of the spectrum). That said, I'm sure some form of balance can be achieved.
When I tried to work on it using the M101 tutorial on youtube it just got worse. As there any hope or should I just trash it? My guide scope should arrive this week :obscene-drinkingcheers:
Cool! You should be really in business with a guide scope... :twisted:
I reckon there is definitely hope for the data - would love to have a go!

EDIT: just saw you posted the data - will have a go now and report back.

Cheers,

Ivo
Ivo Jager
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Re: M42 and M31question

Post by admin »

Ok, here is what I ended up with in 1.3.5 with a very quick & standard workflow;
M42PIHighSig.jpg
M42PIHighSig.jpg (184.19 KiB) Viewed 9384 times
The color is (unfortunately) typical for a CLS filter - a lack of yellow (as this part of the spectrum is filtered out). Nevertheless, different interesting areas with distinctly differing chemical makeups can be clearly distinguished - the slighter green of the OIII rich core, the dominant red H-alpha line and the H-Beta at the fringes. Despite the lack of yellow, there is a hint of a star color continuum as well (red->orange->yellow->white->blue).
What is really cool is that your unguided tracking was so good that you actually managed to resolve the trapezium stars individually - very, very nice indeed! :thumbsup:

So here is what I did;

--- Auto Develop
Default parameters. To see what we got.
Large red bias, quite a bit of noise, oversampling.
--- Bin
I decide to bin the data due to noise and oversampling.
Parameter [Scale] set to [(scale/noise reduction 35.38%)/(798.89%)/(+3.00 bits)]
--- Wipe
I Wipe with default settings, but I discover some (faint) stacking related oddities at the edges. So I undo and launch the crop module.
--- Crop
Parameter [X1] set to [16 pixels]
Parameter [Y1] set to [16 pixels]
Parameter [X2] set to [1717 pixels (-10)]
Parameter [Y2] set to [1113 pixels (-20)]
--- Wipe
Back in Wipe.
I decide to set parameter [Dark Anomaly Filter] to [2 pixels] just in case the noise causes any bad dips in the background, which could potentially confuse Wipe.
--- Auto Develop
I use AutoDev with an ROI over the M42 complex to optimise the global stretch for M42 mainly (since it's the most prominent featuring object).
To make AutoDev ignore fine noise, I set parameter [Ignore Fine Detail <] to [2.9 pixels]
You'll notice how AutoDev really allocates dynamic range in the most optimal way. The dynamic range differences in M42 are *huge*, yet AutoDev manages to show both the faint outer edges of the complex and show the *much* brighter core.
--- Deconvolution
Deconvolution did a lot for your image, though I had to tweak the autogenerated mask a little to prevent ringing artifacts from occuring (I used the 'Stars' preset in Mask->Auto, instead of Decon's Auto Generate feature, then Grow x2, and Invert). I gave special treatment to the trapezium, so that the 'gap' wasn't too big.
The Decon default values did the rest!
--- Wavelet Sharpen
Created a mask with the brightest stars masked out (again, Mask->Auto, Decon, Grow, Grow, Invert).
Parameter [Amount] set to [175 %]
Parameter [Small Detail Bias] set to [89 %]
It did a nice job of accentuating some detail.
--- Color
Default parameters.
--- Wavelet De-Noise
Parameter [Read Noise Compensation] set to [1.99 %]

And that's it! I rotated the image for the more typical way of presenting M42 and M43, but, like almost all things done here, that's up to personal taste. :)

Any idea what would cause the purple dots at the center of your stars? I noticed them in even the linear data...
Ivo Jager
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torsinadoc
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Re: M42 and M31question

Post by torsinadoc »

well heck. I clearly have a lot to learn. Thanks. Ill play around with it some more

No idea on the purple dots.
torsinadoc
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Re: M42 and M31question

Post by torsinadoc »

when making an ROI did you select the entire M42 or jus the trapezium and surrounding areas? I get confused on what to sample

thanks
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Re: M42 and M31question

Post by admin »

torsinadoc wrote:when making an ROI did you select the entire M42 or jus the trapezium and surrounding areas? I get confused on what to sample
thanks
It's whatever Region you think is 'Of Interest'. I took the whole of M42 as my region of interest (including the faint bits far away from the core).
Ivo Jager
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torsinadoc
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Re: M42 and M31question

Post by torsinadoc »

how cow what did I do wrong (it is the first image above M31 that is really blue)

I bind then tried to fix the star shapes with repair then turned on tracking and tried a wipe. See the very interesting result.
I actually did something similar during the M45 processing example posted sometime ago. I assumed that the RGB image gradient was due to the stacking artifact but now I suspect it is just due to human error on my part. This is a DSS stacked image saved in tif but converted to fit. PI would not stack the image as it would not recognize the stars. clearly not a good picture but I'm just trying to learn various ways to fix my poor quality images. Guide scope arrived today which should allow some dithering and hopefully help!

https://drive.google.com/file/d/0B1w8Ns ... sp=sharing



StarTools 1.3.5.273
-----------------------------------------------------------
File loaded [/Users/alandiamond/Documents/Astronomy/Stacked need processing/m31.fit].
---
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
--- Auto Develop
Parameter [Ignore Fine Detail <] set to [Off]
Parameter [Outside ROI Influence] set to [15 %]
--- Repair
Parameter [Radial Samples] set to [32]
Parameter [Sub Sampling] set to [4x]
Parameter [Algorithm] set to [Debloom (Vertical Streaks)]
Parameter [Grow Mask] set to [0 pixels]
--- Layer
Parameter [Layer Mode] set to [Blend]
Parameter [Cap Mode] set to [Clip]
Parameter [Brightness Mask Mode] set to [Off]
Parameter [Filter Type] set to [Gaussian (Fg)]
Parameter [Blend Amount] set to [100 %]
Parameter [Mask Fuzz] set to [4.0 pixels]
Parameter [Filter Kernel Radius] set to [4.0 pixels]
Parameter [Offset X] set to [0.0 pixels]
Parameter [Offset Y] set to [0.0 pixels]
Parameter [Brightness Mask Power] set to [1.00]
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Re: M42 and M31question

Post by admin »

Wow... Something funky going on there with the Wipe module... :shock:
Any chance you could share the data with me?
Ivo Jager
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