Author Topic: How to star align rotated images  (Read 3035 times)

Offline strivedi

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How to star align rotated images
« on: 2014 July 06 19:22:33 »
Hi

I am having trouble aligning images that have a rotation that is not a multiple of 90 degrees. Is there some way I can align them using star or dynamic alignment or some other method?

Shailesh

Offline Alejandro Tombolini

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Re: How to star align rotated images
« Reply #1 on: 2014 July 06 19:30:57 »
Hi Shailesh, StarAlignment does it. Just Add your files into the tool, select a reference image and apply global.

Saludos, Alejandro. 

Offline strivedi

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Re: How to star align rotated images
« Reply #2 on: 2014 July 08 09:45:05 »
Alejandro,

Star alignment could not handle it.

I had two sets of images that were rotated with respect to each other, so I ended up doing a star alignment on each set separately. Then integrated them into two individual images.

Then I did dynamic alignment where I could actually move target stars to match across the two images. That did the trick.

Shailesh

Offline Juan Conejero

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Re: How to star align rotated images
« Reply #3 on: 2014 July 08 09:50:35 »
Hi Shailesh,

Quote
Star alignment could not handle it.

That cannot happen. Do you have mirrored images? Polygonal descriptors (quads, pentagons, etc.) cannot handle specular transformations. In such case you can select triangle similarity. Open the StarAlignment tool, open the Star Matching section, and see the Descriptor type parameter. Can you upload these images, so we can do some tests?
Juan Conejero
PixInsight Development Team
http://pixinsight.com/

Offline strivedi

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Re: How to star align rotated images
« Reply #4 on: 2014 July 08 19:09:12 »
Juan,

I was using the default star matching (pentagons). When I changed it to triangle similarity, I got all images to align correctly. Thanks for the tip.

Shailesh