Aastro123 avatar
Hello! I am doing a mosaic of the Sadar region, hoping to go from the crescent nebula all the way to the North America Nebula using the redcat 51 and asi1600mm. Im approaching 30hrs total integration time of just Ha data, but Im having some annoying problems stitching the photos together. The final image will have about 15 panels. 

I have been using the instructions of "Easy Mosaics" from Windy City Astrophotography on youtube. I have about 10-15% overlap with my first few images, but found it very difficult, (or impossible) to stitch the images together with star alignment in pixinsight. On the panels that I found it impossible to align, I took some images last night with about 50% overlap to kinda "glue" the images together. Despite having  MORE THAN ENOUGH overlap now, pixinsight still finds there to be no punitive star matches, and fails at creating the template for gradientMergeMosaic. Ive tried playing around with the settings in star alignment with no success, Ill have an image below with my settings. 

I have noticed the focus to be slightly off on the top right of a couple images, probably caused by my OAG not being perfectly flush in the imaging train. I have fixed this now, but I would still think star alignment would work. I dont think this is the cause of my problems, but it is worth mentioning since it doesnt help. The images are also drizzled x2 from DSS. The images have been cropped to remove artifacts, and DBE has been performed. Images remain in a linear state. 

Im not entirely sure what to do. I probably bit off more than I could chew with creating such a large mosaic, but here we are now! If anyone has any suggestions or other ways of creating mosaics PLEASE LET ME KNOW. I feel like Ive hit a brick wall.... 

EDIT: I have been able to mosaic some of the images, as seen below in the pics. But this is as many photos that will stitch together, the others do not work 
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andrea tasselli avatar
I suggest you use the MosaicByCoordinates script instead, being careful in reading the help file (for once there is one!) together with the attendant PhotometricMosaic.
Aastro123 avatar
andrea tasselli:
I suggest you use the MosaicByCoordinates script instead, being careful in reading the help file (for once there is one!) together with the attendant PhotometricMosaic.

***The MBC script works great! thank you!
Jeff Coldrey avatar
I have not used the MBC script. 
But with StarAlignment:
- disable “restrict to previews” if previews  not being used to define overlap areas
- crop any black borders off overlapping regions
- having frames in correct orientation often helps
- if linear frames are very faint, using a stretched (HT-STF) version sometimes works

Hope that helps, and good luck. 
Jeff
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Mike Dobres avatar
HI
 I havent used the Pixinsight script, but have twice used NINAs framing assistant and  Microsoft ICE to make 6 and 8 panel mosaics of the rosette nebula and horsehead and flame nebula. Perhaps  try a quick test using ICE - and see if it can stitch your panels together. 

https://astrob.in/0hzbm1/C/

https://astrob.in/zz6dn2/C/


 I followed  Pat Prokop instructions for most of this workflow. He recommends 30% overlap. (https://youtu.be/3WXSzwG38U8).

Good luck!

Mike
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