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Mosaic Processing Not Working
I am having a lot of issues getting AstroPixelProcessor to process a mosaic. I've got a six panel mosaic of EtaCarina done with a one shot colour camera. I've been using APP for about 10mths and can process individual images at a basic level now, so I've some of the basic's down. I've got 6 x 25subs, with a ~20% overlap, and am processing with a bad pixel map, master dark/flat/bias. The individual panels are coming out OK enough.
I've tried two methods to process this
- process all the subs in one run as per some of the videos
- process each panel, then load each integrated
I either get like a "rainbow" or I get a stitched together image where the blending is horrible. Neither are an acceptable.
In the attachments I have where I've processed all six panels, didn't any further post processing (remove LP etc) and just save as a jpg and then put them on the screen in the right order and taken a screen shot. This is how APP should be processing the image I think. I've also attached sample images of the rainbow effect as well as two examples of the image where at least it processed, but the blending is horrible.
I had LNC with multiple iterations, scale moved to 1-10 from the default, MBB at 20%, registration mode set to mosaic etc. These are all settings I've seen in the videos and tried to follow. I also set it to 2000 stars in analyse stars. The subs are pretty clean as they are from a darker sky site too. I've been trying various different options for a couple of weeks now and am making no progress with having an even passable image.
Can anyone help with what is going wrong here please?
Thank you, Craig
For you rainbow issue, try to click the OpenGL button.
To improve the merging of your different tiles, you can also try :
- set 3000 stars in step 3
- uncheck dynamic distortion and same camera/lens in step 4
- in step 5, what mode has been selected, regular or advanced ?
Maybe some informations there : https://www.astropixelprocessor.com/community/main-forum/some-questions-for-creating-a-mosaic/#post-5805
Thanks for these tips David.
I had stars set at 2000, not 3000. I did have dynamic distortion and same camera enabled from memory and will go back and uncheck those. For step 5, I set this to advanced from regular because I saw Mabula do this in one of his video's. I'll go back and read that URL you posted too, thanks for that.
I'll report back with the result. I hope this works as one of the reasons I got into Astrophotogrpahy was to do mosaics as well and to date APP has not produced a decent result. Hoping these setting tips do the trick.
No, this did not seem to make any different in relation to the rainbow.
I have gone back and tried to re-process all the 150 subs (6 x 25subs per panel) with the suggested settings mentioned above. This is taking, literally, days and it still hasn't finished yet. I am making no progress here by the looks of it. Wondering if this is a Mac thing or not? Because all the video's I see its using Windows and this Mosaic tool seems easy. I've had no success with any of the Mosaic's I've attempted with APP, in spite of getting OK results with single images.
Here is the link in WeTransfer to the 6 panels https://we.tl/t-x5HJCWTEYq if anyone wants to have a look and let me know what I've been doing wrong that'd be great!!!
Each panel has been
- stacked (25subs each panel) with a bad pixel map, master dark/flat/bias. Calibration frames were all created with APP as well and stacked in APP
- no remove LP / calibrate background etc etc, they are just stacked and left in FITS format
I did get it to process last night using these updated settings, but was then unable to do any remove LP, calibrate background. The image was entirely washed out and I couldn't bring it back when trying to apply removeLP to the combined image. But at least there was some progress to get a stitched image. The panel's weren't well integrated though colour wise, but at least there was improvement on the smudging between panels.
My apologies, again, for the lack of support lately. Mabula will inform everyone as for the reasons why.
Thanks for sharing the data, that might give us a better idea. Also, what software did you use to capture the mosaic and what was the selected overlap in % (edit: sorry, 20% as you mentioned). It might be good for us to see a few of your calibration darks/flats as well.
It shouldn't matter on which platform this is done (the mosaic process itself), the rainbow effect might have something to do with OpenGL and Mabula is at least working on getting APP to work way better with GPU support and more recent graphics libraries.
I downloaded the data and am looking at the separate panels. I do see a lot of color issues it seems in the background, could you upload like 10 light frames from 1 panel and your masterdark and masterflat? Besides that the stars themselves seem a bit strange as well, there's definitely distortion in them and something is really off if you look at the bottom right corner of panel 4 for instance. I'm curious if this is also the case in the separate frames. If so, something might be wrong with your optics which can cause troubles with nicely aligning the frames. Even though APP still seems to be able to do it given your further results. I'll now try the mosaic myself as well.
So this end result is still pretty bad, but at least the frames were registered properly without artefacts as far as I can see. The differences in the background are still big as that problem lies within the data and can't be solved without some serious work. I tried to control it in the seperate frames, but it didn't help too much, even made the middle of the nebula a bit too bright (I think my normalization went wrong here).
I used a scale start of 4, scale stop of 12, distortion margin of 3. These are big numbers, but I figured it might be necessary given the visible distortion. In the integration tab I used 5% MBB, 1st degree LNC with 4 iterations.
I captured this with a EdgeHD 8" with Hyperstar, so its a 400mm focal length setup at f/2 and these are 60 second subs. Capture software is Kstars/EKOS and the camera is a ZWO ASI 1600MCPro cooled to -10 with a gain of 139 (unity), so a one shot colour camera.
That last image there is a drastic improvement in what i have been able to achieve. Can I ask what settings you used to get that with? That's clearly where I need to be as a base position, you've done a far better job there.
I'll upload some of the lights and the masters I used as well shortly. Thank you so much for getting back to me here, this has been hard to make some progress on this and its great to get some help with it.
I posted some of the setting above the photo. I still didn't like the result in the sense of some over-correction, yours are far better exposure-wise so also in my processing something went a bit wrong. You might try the mosaic with those settings, then try to clean up the result. But there seems to be some reflection in your setup which shows as these center rings. This might also affect a proper calibration (not sure). Such a fast system can be very tricky (though it's awesome to have).
edit: You might even lower the exposure a bit as this target is pretty bright to begin with for F2. And nice to see a fellow EKOS user (I use both EKOS and SGP whichever I feel like trying 🙂 ).
With the LP I meant reflection, as in a problem with light pollution inside your optic-train (or so it seems). The LP correction in APP accounts for LP from city light for instance, causing a gradient in the sky. This however if of a different kind that the LP correction can't solve. Just to bring that to your attention as something you might want to look into.
Thanks for uploading the other data!
OK, here is a 2nd link of a single panel's lights as well as the calibration frames I used in APP to process them https://we.tl/t-2l86gZtSdP