Stacking Seestar S50 2xframing mosaic lights?
Stacking program, astrometric (plate) solver, fits file viewer
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Hello, this is my first contact with Astap and after several attempts I have not found a solution to stack the raw material from the SeeStar S50.
The material is only available as lights in fit format and was recorded as a mosaic in 2x framing mode. The Seestar arranges the fits in AZ mode in a spiral from the inside to the outside until the double sensor area is 100% covered.
I couldn't really find what I was looking for in the manual.
I even included the master in the stack to set the image resolution but the result is blotchy.
Is Astap even able to handle AZ material including field rotation or process this type of mosaic?
CS
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Hi Fedorauser,
For a mosaic ASTAP will solve the images and then stick them together using the astrometric positions of the pixels. Rotation and overlap will be dealt with. But for each position you should have only one image with some overlap. If you have more then one image from an area, you should first stack them.
Does that work for you?
Cheers, Han
That's the problem with it because the Seestar creates a deliberate dithering and I have thousands of frames with offset to process.
These cannot be stacked as a group and then joined together.
The best I could do is offset the finished framing mosaic stack from the Seestar with other framing mosaic stacks.
It would be interesting if they could integrate this function into an upcoming Astap version, as the Smart Telescopes from the providers all work in this direction.
If you are interested I can send you a raw stack.
Nevertheless a great program.
I have another question about platesolving. I can access the Astap Solver with the SAS SetiAstroSuite software under Windows and MacOS, but under Linux I always get an error message even though the paths have been set correctly /opt/astap/astap. I could not find the problem in the documentation.
Share a link to a set of sample images so I can have a look.
Han
Hello Han, that's the link to the files CS
https://drive.google.com/drive/folders/1pI4k5zSTEcnTm_UXMdJytaBlgv1IZESX?usp=sharing
I have the images on my laptop but keep them available till tomorrow because I have to download them to my desktop.
Okay it can see what you already told me that the Seestar is moving in a spiral around the center. The optical distortion of the image is very small. This is important if you want to stack them with an overlap.
I will have look again tomorrow. One problem is the amount of images. ASTAP can stick the images together by calculating n the astrometric position of each pixel. This is very CPU intensive and to do this for a few hundered images will take a very very long time to process.
Han
Last edit: han.k 2025-02-18
Thanks for the feedback and similar to your description I tried to implement it but at the frame edges I get strong patterns at the transitions with sigma clip average.
When I use finished stacks from the Seestar (6 parts of M31) in Astrometric image stitching mode it works perfectly.
My biggest stack was 10000 fits and that requires a cpu cluster :)
I'll leave the demo material on the drive and take it down when they say so.
good evening MK
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The ASTAP mosaic stack routine will handle it if you select option merge overlapping backgrounds. I have done it for the first ten images. But it is very slow. It took 45 minutes on my laptop. So on a fast desktop it could take up to a day for a few hunderd images. See attached.
To make it faster it would require to speed up the routine. Maybe calculating the new pixel positions each tenth pixel position and then interpolate to speedup. This would avoid a lot of goniometry calculations. See attached.
I will have an other look tomorrow.
Cheers, Han
Brighter
Thanks for the test.
I have started a test and integrated the final stack from the Seestar into the stack as a master and adapted the other fits to the size of the master.
Should work with sigma mode but the average mode makes a pattern in the stack
Last edit: fedorauser 2025-02-18
Good morning,
Yesterday I also did an image stitching mode test with 6 finished mosaic segments on an Apple M1 computer.
This test failed with an error message although the test ran without problems on a Linux and Windows11 installation.
This is the error message
08:29:50 Stack method Image stitching mode
08:29:50 Analysing lights.
08:29:50 Grayscale stack (classify by light filter unchecked)
08:29:50 Stacking (Image stitching mode), HOLD ESC key to abort.
08:29:50 Checking astrometric solutions
08:29:50 Astrometric solutions complete.
08:29:50 Sorted list on RA, DEC position to place tiles in the correct sequence.
No images in tab lights to stack.
Hint: check field of view camera in tab alignment.
Morning,
I assume there where no astronomical solutions found. If so the images are unchecked. Then it concludes there are no images left...
Solving of your images should be easy. Check if the images are solved. It should indicate in the status bar the ra,dec position of your mouse pointer. Can you re-solve an image?
I will do a check /testthis later afternoon on my old Mac X86_64
Han
Thanks, but the astronomical solution has already been found.
The funny thing is that it fails with the same material on three systems only on MacOS Applesilicon.
I get the same data via a NAS and that's why it raised this question.
Is there an explanation why I cannot access the solver from ASTAP from SetiAstroSuite only on Linux(Ubuntu24.4.2)? This works fine on Windows and MacOS.
I know the ghost in the machine is loose.
Best regards and CS from Vienna
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No this is weird. I works on my older Mac laptop with a X86_64 cpu. See attached.
So for me it currently almost impossible top trace the proplem. I had a similar report on SQM measurement failure on a M1 Mac.
The only way to fix it would be that I get remote access to a M1 Mac via remote desktop/teamviewer/Anydesk or something simular. Install the compiler and debugger run the ASTAP code and trace the bug. I just need a volunteer for that.
Cheers, Han
Hi, thanks for the feedback and I am too little of a programmer in these things to be able to support this skillfully.
I have not tested the possibility of the mosaic stack with the M42 material but 6x M31 ready developed stacks that I wanted to put together.
I have found a workflow for the spiral stack from the Seestar and just wanted to ask if I am moving in the wrong direction.
Am I making a mistake mixing this material?
Best regards MK
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Sigma clip will not work for a mosaic ensemble. Sigma clip will only work if you stack images of the same celestial location. Then it can calculate an average and remove outliers by comparing each pixel with the average of that celestial location.
A mosaic is combing images of different celestial locations and nothing is identical except for the overlap.
To create a mosaic to have to select in the in tab "stack method", stack method "image stiching mode".
The light have to be in tab lights. Then just press stack with the method "image stiching mode" selected.
Correct attachment
Hello and thank you for your reply.
We are talking past each other and I am expressing myself misleadingly and am trying to formulate it better.
The Seestar produces a finished stack with twice the sensor size that is installed in the seestar in 1920x1080.
This stack has a maximum dimension of 3840x 2160.
These individual fits in the Lights Folder should be stacked to 3840x2160 and this is in principle not a real mosaic but a framing or extreme dithering applied by ZWO as an algorithm.
I have tested that the process works with Sigma Clip Average and this can be verified with the demo material.
The question is whether these different fit types (master stack and RAW fit) can be processed correctly, as marked in the image.
In Siril, for example, there is the Framing Max variant, which performs frame blending at the edges of the image by x pixels and selects the area based on the star position or using the Platesolver from the Fits header via the database.
The Image Stitching Mode works extremely well on AppleSOC Macs with finished stacks, only for the actual stacking of thousands of files would a render farm be required.
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You probably could mix different image dimensions. But the pixels size in arcseconds should be the same. The final dimensions will be dictated by the reference image with is indicated by a crown. This reference image is selected automatically as the best & sharpest image. You have no control on this selection.
Last edit: han.k 2025-02-20
That was the answer I was waiting for and the fits are stacked on this master frame and rendered into the final master stack.
The result is correct as far as the dimensions are concerned and the alignment should also be correct.
Thanks in any case for the explanation and the help
CS
I wanted to download your files to my desktop but they are already in the bin according Google.
At the moment I'm busy here with some other things, but in the long run I want to modify ASTAP to use more threads/cpu's to speed up the processing
Han
I thought you had already downloaded them...
I will send you more material if you like...
if you want you can also have material from Celestron Origin which is also a smart telescope but the stack is prepared differently.
I uploaded new files and sent the links as PM
Thanks. I have the files.
I will now first concentrate on threads/multi-core use. That should improve the processing with a factor four. And there are some other none-computer related projects to do here.
Then I wish you a lot of success in implementing projects