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(@thompeters)
Main Sequence Star Customer
Joined: 1 year  ago
Posts: 38
October 1, 2018 20:50  

6 Panel mosaic constructed in SGP with 15% overlap. Each panel is of different duration. Nos 1, 2 & 5 are 3 hours each, 6 & 3 are 2.5 hr, and Panel 4 is .9 hr.

Used mosaic registration using Quads, start - 1 stop - 10, integrate weights equal integration = Avg, with 2nd deg LNC @ 3 iter. with 10% MBB

 

M 31 Andromedea Galaxy   6 panel Mosiac 8 x 10 Web size APP

This topic was modified 1 month  ago by thompeters

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(@mabula-admin)
Quasar Admin
Joined: 2 years  ago
Posts: 1797
October 2, 2018 18:20  

Excellent Thom @thompeters, great image for so little exposure time per mosaic panel.

Perhaps you can further improve this result? I think there are still some gradients left and the blueish spiral arms can be possible be a bit more blue.

Did you use the remove light pollution tool and star color calibration?

Cheers,

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@thompeters)
Main Sequence Star Customer
Joined: 1 year  ago
Posts: 38
October 2, 2018 18:59  
Posted by: Mabula Haverkamp - Admin

Excellent Thom @thompeters, great image for so little exposure time per mosaic panel.

Perhaps you can further improve this result? I think there are still some gradients left and the blueish spiral arms can be possible be a bit more blue.

Did you use the remove light pollution tool and star color calibration?

Cheers,

Mabula

Yes I do plan on getting more time on this image. I originally used only a 5% overlap on the panels and never could get a mosaic integration to work, so this is a 15% overlap which does work. 

I did use both light pollution and star calibration tools on this image. In fact I did 2 runs of the LP tool on the compleated mosaic. Plus I ran the LP tool only, on each panel prior to running the mosaic integration. I was frustrated too that I still had gradients which I could not remove no matter how I tried! :((

Then after mosaic integration w/ 2 LP, a BG neutralization, then SCC. I also used the Sel. Color tool to bring out the blue, but failed to get much blue. Maybe because I understand this tool the least! 🙁

I’ve spent the last 3 weeks trying to get the mosaic integration to work correctly. Played around with the LP tool on both panels and mosaic, and tried different LNC settings to get a good mosaic.

I’ve watched Your video on the mosaic creation several times to better understand the process too,  after a number of early failures. I’d rather experiment so I can learn the controls better than asking for help early on. 😉


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(@mabula-admin)
Quasar Admin
Joined: 2 years  ago
Posts: 1797
October 14, 2018 20:54  

Hi Thom @thompeters,

Yes, with only 5% overlap, chances are big that too little stars are detected needed for registration.

With a little bit more overlap, things will work much better. I would advise to have at least 10% and preferably 15%.

Getting out the blues in the spiral arms should be possible without the use of Selective Color normally. A reason for not getting nice blues could be bad atmospheric conditions when you shot the data and/or perhaps very low signal in the blue channel compared to the green and red channel. The histogram will often tell you this. Then the Blue histogram peak would be much wider then the Red and Green histogram peak after Background Neutralization. Was this the case perhaps?

If you send me the integration file of the mosaic I will be happy to have a look and suggest what and how you could improve this 😉

I am sure we should be able to get a better/flatter background and  perhaps better blues in the spiral arms...

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@thompeters)
Main Sequence Star Customer
Joined: 1 year  ago
Posts: 38
October 14, 2018 23:43  

Sure I will send it to you!!

And this is a 15% overlap. I’d said the 5% DID NOT WORK. But the 15% did work. 

Not sure I looked at the histogram after BG neutralization. 

 

Thom


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(@thompeters)
Main Sequence Star Customer
Joined: 1 year  ago
Posts: 38
October 15, 2018 15:18  

Files have been uploaded to you! @Mabula Haverkamp - Admin


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(@mabula-admin)
Quasar Admin
Joined: 2 years  ago
Posts: 1797
October 15, 2018 20:29  
Posted by: thompeters

Sure I will send it to you!!

And this is a 15% overlap. I’d said the 5% DID NOT WORK. But the 15% did work. 

Not sure I looked at the histogram after BG neutralization. 

 

Thom

Hi Thom @thompeters,

Yes, I know you used 15%, I just mentioned that that should be safe 😉

I have downloaded the files and I am working on it now...

First of all, I think the Ligh Pollution correction on the individual frames is making things a bit more complicated.

You have sent me the mosaic panels already corrected with the Remove Light Pollution tool. But I have registered these and integrated these.

I tried integrating with MBB at 15% and LNC 1st and 4th degree and then further correcting the result with the Remove Light Pollution tool:

With LNC 4th degree the outcome is rather bad, which to me, indicates that the LP correction on the individual panels is probably not good.

Results are shown with strong stretch and saturation to show the problems.

Result with LNC 1st degree and LP correction on the result:

LNC 1stdegree LPC

Result with LNC 4th degree and LP correction on the result:

LNC 4th degree LPC

It is clear that correction is very difficult now. I would think that working with the mosaic panels that are not yet corrected for LP would be easier. Wasn't it ?

This is the result that I can get from the LNC 1st degree mosaic now after Star Color Calibration :

LNC 1stdegree LPC StarColorCalibration

The problems probably are also partly due to mixed atmospheric conditions while gathering the data per mosaic panel. Perhaps with more data, the result will start to improve.

In my experience, if you apply Light Pollution Correction on mosaic panels, you need to be very carefull, so I think this could have complicated things in this case. But is't is hard to tell without seeing the mosaic panels that are uncorrected for LP.

Kind regards,

Mabula

 

 

 

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@thompeters)
Main Sequence Star Customer
Joined: 1 year  ago
Posts: 38
October 16, 2018 19:25  
Posted by: Mabula Haverkamp - Admin
Posted by: thompeters

Sure I will send it to you!!

And this is a 15% overlap. I’d said the 5% DID NOT WORK. But the 15% did work. 

Not sure I looked at the histogram after BG neutralization. 

 

Thom

Hi Thom @thompeters,

Yes, I know you used 15%, I just mentioned that that should be safe 😉

I have downloaded the files and I am working on it now...

First of all, I think the Ligh Pollution correction on the individual frames is making things a bit more complicated.

You have sent me the mosaic panels already corrected with the Remove Light Pollution tool. But I have registered these and integrated these.

I tried integrating with MBB at 15% and LNC 1st and 4th degree and then further correcting the result with the Remove Light Pollution tool:

With LNC 4th degree the outcome is rather bad, which to me, indicates that the LP correction on the individual panels is probably not good.

Results are shown with strong stretch and saturation to show the problems.

Result with LNC 1st degree and LP correction on the result:

-- attachment is not available --

Result with LNC 4th degree and LP correction on the result:

-- attachment is not available --

It is clear that correction is very difficult now. I would think that working with the mosaic panels that are not yet corrected for LP would be easier. Wasn't it ?

This is the result that I can get from the LNC 1st degree mosaic now after Star Color Calibration :

-- attachment is not available --

The problems probably are also partly due to mixed atmospheric conditions while gathering the data per mosaic panel. Perhaps with more data, the result will start to improve.

In my experience, if you apply Light Pollution Correction on mosaic panels, you need to be very carefull, so I think this could have complicated things in this case. But is't is hard to tell without seeing the mosaic panels that are uncorrected for LP.

Kind regards,

Mabula

 

 

 

Mabula

I'm currently redoing the mosaic with panels which have NOT had LPC.  Please explain what "Flexibility" does in the LPC tool?? Is it better to use small or larger boxes in the LPC tool??

Also I;m not sure how to go about the LNC calcs for the mosaic! I start off with 1st deg. 3 reps, and keep stepping up the degree, but keeping 3 reps.  but I've never used 4th deg. like you did. Is there an advantage to doing 4th or higher at some point?? Or is there some logic I can use for increasing the degree of LNC?

I can send you the panel integration w/o LPC too if you wish!

Thom

This post was modified 4 weeks  ago by thompeters

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