Author Topic: Another Mosaicing problem . . .GMM Making a Mess  (Read 7322 times)

Offline Terry Danks

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Another Mosaicing problem . . .GMM Making a Mess
« on: 2020 March 03 08:51:55 »
Seems were are still unable to attach images to the forum??

To get around that, I link to an image uploaded to my personal web site:
http://danks.netfirms.com/GMM%20Problem.JPG

It shows the results, before and after, of a registered WCS file from the MBC tool when the GMM tool is run to knit two panels together.
The GMM process seems to have turned all fainter stars into doubles, with really faint stars appearing as streaks, as if they were trailed.
It is not really apparent at a "normal" viewing magnification. The degree of magnification can be judged by the sliders.
Is this to be considered a normal result of GMM? Is there a setting to minimize, or eliminate it?

Offline pfile

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Re: Another Mosaicing problem . . .GMM Making a Mess
« Reply #1 on: 2020 March 03 09:04:50 »
GMM just does what it does blindly, with what it's given. so it means the input images don't line up right.

i think andres has addressed problems like this before - you need to configure ImageSolver to do Distortion Correction, and then also i think tell MosaicByCoordinates to use high quality registration. i think that takes care of distortions such as yours.

rob

Offline Terry Danks

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Re: Another Mosaicing problem . . .GMM Making a Mess
« Reply #2 on: 2020 March 03 11:36:22 »
Thanks, Rob.

Apparently I had neglected to do two things.
1/ Enable Distortion Correction in the Image Solver, and . . .
2/ Select Options>High Quality in the MBC tool

So, both of your suggestions were entirely correct! Thank-you!

All well now.

Offline pfile

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Re: Another Mosaicing problem . . .GMM Making a Mess
« Reply #3 on: 2020 March 03 12:13:27 »
cool, glad to hear that fixed you up.