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initial processing artefacts

Posted: Mon Aug 26, 2019 7:01 pm
by Burly
hi ivo im just experimenting with some data ,currently processing 3 nights data of M31 ,so i have data from one night just playing around to see whats in the image ,now i know you only use auto dev not manual dev ,so i have cropped image ,used auto dev ,wipe manual dark anomaly 6 pixels , manual dev, then screen shot image ,in the image you see the white areas i dont know what you describe it as, gradients ? how do i get rid of this before preceeding i sometimes see this when using auto dev wipe autodev ,so just trying to understand what it is and the best way to eradicate this ,it may be i started imaging whilst M31 was still to low down and maybe waited until it had risen higher or maybe i should restack omitting a few early subs.note bias frames loaded as darks and flats used ,dithered images

regards Dave

Re: initial processing artefacts

Posted: Mon Aug 26, 2019 9:29 pm
by Rkonrad
HI Dave,

I'd love to see your stacked tif or fit if that's possible.

Richard

Re: initial processing artefacts

Posted: Tue Aug 27, 2019 3:36 am
by admin
Hi Dave,

This looks like a classic halo around a dust speck that wasn't masked out (or better yet - caught by your flats). This "halo" with a hole in the middle is caused by Wipe backing off locally so it doesn't clip the darker-than-the-rest-of-the-background-feature. You can see a very similar signature here;
https://www.startools.org/modules/wipe/ ... aring-data
Image


Try masking out the black spot before running Wipe and see if the issue persists. Cheers!

Re: initial processing artefacts

Posted: Tue Aug 27, 2019 4:41 am
by Burly
Thanks ivo ,i have now processed three 3 nights data here comments welcome ,i changed dither setting to random in phd2 but i prefer spiral so next time i will change back ,there is about 5.50 hrs data stacked in regim i will try DSS now it has been updated to see if there is a difference in end stack , https://www.dropbox.com/s/nc3do1rcprflt ... s.tif?dl=0 and seemed to process better note i have cropped borders ,richard that file is here from the single night https://www.dropbox.com/s/3ynzrybez6azu ... s.tif?dl=0
https://flic.kr/p/2h676iC

Re: initial processing artefacts

Posted: Tue Aug 27, 2019 9:33 pm
by Burly
upgraded to 1.5 tried on my M31 x3 combined data ,really struggling there is a red cast and getting lost trying to rid the red cast ,could someone have a look and be able to tell me what the issue is https://www.dropbox.com/s/nc3do1rcprflt ... s.tif?dl=0 so i tried auto dev ,wipe , autodev im lost how to get past this point what am i doing wrong compared to 1.4 there does seem better detail but i didn't have the red cast showing .

regards dave

Re: initial processing artefacts

Posted: Wed Aug 28, 2019 2:33 am
by admin
Burly wrote:upgraded to 1.5 tried on my M31 x3 combined data ,really struggling there is a red cast and getting lost trying to rid the red cast ,could someone have a look and be able to tell me what the issue is https://www.dropbox.com/s/nc3do1rcprflt ... s.tif?dl=0 so i tried auto dev ,wipe , autodev im lost how to get past this point what am i doing wrong compared to 1.4 there does seem better detail but i didn't have the red cast showing .

regards dave
Hi Dave,

I'm a little unsure of what the problem might be you are experiencing; the dataset comes up nicely with a very standard workflow?
M31x3CombinedFiles.jpg
M31x3CombinedFiles.jpg (215.35 KiB) Viewed 6308 times
File loaded [/home/ivojager/Downloads/M31x3CombinedFiles.tif].
--- Auto Develop
To see what we got.
We can see oversampling, heavy light pollution or bias.
--- Bin
To reduce oversampling.
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
Image size is 1905 x 1196
--- Wipe
Default parameters.
Severe stacking artifacts become visible.
--- Auto Develop
Default parameters.
--- Crop
Cropping away stacking artifacts.
Parameter [X1] set to [320 pixels]
Parameter [Y1] set to [238 pixels]
Parameter [X2] set to [1528 pixels (-342)]
Parameter [Y2] set to [952 pixels (-211)]
Image size is 1208 x 714
--- Restore
Original
--- Wipe
Default parameters.
Parameter [Dark Anomaly Filter] set to [4 pixels]
--- Auto Develop
Final global stretch
Parameter [Ignore Fine Detail <] set to [2.7 pixels]
Parameter [Outside RoI Influence] set to [50 %]
Parameter [RoI X1] set to [441 pixels]
Parameter [RoI Y1] set to [266 pixels]
Parameter [RoI X2] set to [753 pixels (-455)]
Parameter [RoI Y2] set to [507 pixels (-207)]
--- Deconvolution
Auto mask.
Parameter [Image Type] set to [Deep Space]
Parameter [Mask Behavior] set to [De-ring Mask Gaps, Hide Result]
Parameter [Radius] set to [1.5 pixels]
Parameter [Iterations] set to [6]
Parameter [Regularization] set to [1.00 (optimal noise and detail)]
Parameter [Mask Fuzz] set to [4.0 pixels]
--- HDR
To taste. M31's core is a perfect candidate for the Reveal preset.
--- Color
Parameter [Dark Saturation] set to [Full]
--- Wavelet De-Noise
Default.

Re: initial processing artefacts

Posted: Wed Aug 28, 2019 4:20 am
by Burly
Thank you ivo for taking the time I will have another play later I didn’t use crop as I had already cropped, obviously I had not cropped enough, I also see you used restore maybe this is the important part I have always failed to do , I take it this was causing me to have the red bias I couldn’t get rid of , I live in a town with led street lighting so lps a problem hence using a Idas D2 filter, I will post my result once processed.
Regards Dave

Re: initial processing artefacts

Posted: Thu Aug 29, 2019 12:05 am
by admin
Burly wrote:Thank you ivo for taking the time I will have another play later I didn’t use crop as I had already cropped, obviously I had not cropped enough, I also see you used restore maybe this is the important part I have always failed to do , I take it this was causing me to have the red bias I couldn’t get rid of , I live in a town with led street lighting so lps a problem hence using a Idas D2 filter, I will post my result once processed.
Regards Dave
Let me know how you go Dave. Strabge thing is though, I never saw a red bias of any kind while processing your data... :think:

Re: initial processing artefacts

Posted: Sat Aug 31, 2019 5:53 pm
by Burly
Seems a better result this time ivo i think a lot of the problem has been caused by the first stack ,but never mind all a learning curve
M31x3daves process .jpg
M31x3daves process .jpg (268.58 KiB) Viewed 6223 times
StarTools 1.5.364
Fri Aug 30 20:35:16 2019
-----------------------------------------------------------
File loaded [C:\APT_Images\Camera_1\2019-08-23\M31x3CombinedFiles.tif].
Image size is 3811 x 2392
---
Type of Data: Linear and was Bayered, but not whitebalanced
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
Image size is 1905 x 1196
--- Crop
Parameter [X1] set to [320 pixels]
Parameter [Y1] set to [238 pixels]
Parameter [X2] set to [1528 pixels (-377)]
Parameter [Y2] set to [952 pixels (-244)]
Image size is 1208 x 714
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [4 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 [5.0 pixels]
Parameter [Outside RoI Influence] set to [50 %]
Parameter [RoI X1] set to [0 pixels]
Parameter [RoI Y1] set to [0 pixels]
Parameter [RoI X2] set to [1208 pixels (-0)]
Parameter [RoI Y2] set to [714 pixels (-0)]
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [4 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 [2.7 pixels]
Parameter [Outside RoI Influence] set to [50 %]
Parameter [RoI X1] set to [441 pixels]
Parameter [RoI Y1] set to [226 pixels]
Parameter [RoI X2] set to [753 pixels (-455)]
Parameter [RoI Y2] set to [507 pixels (-207)]
Mask used (BASE64 PNG encoded)


--- Deconvolution
Parameter [Image Type] set to [Deep Space]
Parameter [Mask Behavior] set to [De-ring Mask Gaps, Hide Result]
Parameter [Radius] set to [1.5 pixels]
Parameter [Iterations] set to [6]
Parameter [Regularization] set to [1.00 (optimal noise and detail)]
Parameter [Mask Fuzz] set to [4.0 pixels]
--- HDR
Parameter [Small Detail Precision] set to [Max]
Parameter [Channels] set to [Brightness Only]
Parameter [Algorithm] set to [Reveal DSO Core]
Parameter [Dark/Bright Response] set to [Full]
Parameter [Detail Size Range] set to [1000 pixels]
Parameter [Strength] set to [1.2]
--- Color
Parameter [Cap Green] set to [Sliders Reduce Color Bias]
Parameter [Bias Slider Mode] set to [Scientific (Color Constancy)]
Parameter [Style] set to [Straight CIELab Luminance Retention]
Parameter [LRGB Method Emulation] set to [UNKNOWN]
Parameter [Dark Saturation] set to [2.00]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [200 %]
Parameter [Blue Bias Reduce] set to [1.37]
Parameter [Green Bias Reduce] set to [2.66]
Parameter [Red Bias Reduce] set to [1.00]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [UNKNOWN] set to [0 %]
--- Wavelet Sharpen
Parameter [Structure Size] set to [Large]
--- Wavelet Sharpen
Parameter [Intelligent Enhance] set to [No]
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 %]
--- HDR
Parameter [Small Detail Precision] set to [Max]
Parameter [Channels] set to [Brightness Only]
Parameter [Algorithm] set to [Reveal All]
Parameter [Dark/Bright Response] set to [1.00]
Parameter [Detail Size Range] set to [1000 pixels]
Parameter [Strength] set to [1.2]
--- Color
Parameter [Cap Green] set to [Sliders Reduce Color Bias]
Parameter [Bias Slider Mode] set to [Scientific (Color Constancy)]
Parameter [Style] set to [Straight CIELab Luminance Retention]
Parameter [LRGB Method Emulation] set to [UNKNOWN]
Parameter [Dark Saturation] set to [8.50]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [144 %]
Parameter [Blue Bias Reduce] set to [1.37]
Parameter [Green Bias Reduce] set to [2.66]
Parameter [Red Bias Reduce] set to [1.00]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [UNKNOWN] set to [25 %]
--- Wavelet De-Noise
Parameter [Filter Type] set to [Distance Weighted Outlier Rejection]
Parameter [Grain Size] set to [2.7 pixels]
--- Wavelet De-Noise
Parameter [Scale 1] set to [95 %]
Parameter [Scale 2] set to [95 %]
Parameter [Scale 3] set to [95 %]
Parameter [Scale 4] set to [95 %]
Parameter [Scale 5] set to [0 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Scale Correlation] set to [6]
Parameter [Color Detail Loss] set to [12 %]
Parameter [Brightness Detail Loss] set to [12 %]
Parameter [Grain Dispersion] set to [2.7 pixels]
Parameter [Non-linear Response <] set to [Off]
Parameter [Smoothness] set to [65 %]
---

--- Fractal Flux
Parameter [Brightness Mask Mode] set to [Off]
Parameter [Algorithm] set to [Add Detail]
Parameter [Negative Flux] set to [0 %]
Parameter [Positive Flux] set to [25 %]
Parameter [Detail Filter] set to [2.5 pixels]
Parameter [Filter Fuzz] set to [1.0 pixels]
Parameter [Filter Radius] set to [1.5 pixels]
Parameter [Filter Amount] set to [200 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Brightness Mask Power] set to [1.00]
Type of Data: Linear and was Bayered, but not whitebalanced
File saved [C:\APT_Images\Camera_1\2019-08-23\M31x3daves process .jpg].

Re: initial processing artefacts

Posted: Mon Sep 02, 2019 5:04 am
by admin
Excellent! The purplish HII areas are unmistakeably starting to show up too. :thumbsup: