Aligning OSC and mono images together in Deep Sky Stacker

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David Moore avatar
I can align mono luminance, Ha, O3 and SII images in DSS. However I also want to align OSC and mono images together and DSS won't let me do that as they are mono and OSC even though the cameras produce the same size images. Does anyone know how to do that? Could I convert all the mono to RGB first as I can do that in Photoshop? What I don't want is one image overlaid on top of other as I want to access aligned images in Photoshop so I can combine them how I want. Can Pixinsight do it or Registar? I don't have either yet.
Engaging
andrea tasselli avatar
PI does. At no cost I'd suggest you try SiriL, which can do most of the things you'd ever want an AP program to do. Including the one you just asked.
Rick Veregin avatar
For sure, you can take your best Ha sub and covert to RGB in photoshop. The converted image will be your reference for the color images, the original sub will be the reference for all your mono subs.  Or you can open your best  color image sub exposure in Photoshop then convert and save it as a grayscale image. Use that grayscale image to register the mono images. Use the same color sub to reference all your color images. You don't need to convert a lot of images, just use one good sub exposure as your reference. Either will work, use your best image overall as the reference.
Rick
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David Moore avatar
OK Rick. I will do the conversion you mentioned and then align MONO and OSC in DSS. I think that is what you are suggesting.
Rick Veregin avatar
Yes. To be clear:
1) your best color sub is chosen to be your reference for color images. Register all of your color images with that as the reference. Then stack. This is your registered color stack.
2) the same best color sub is converted to grayscale in PS. Use that to register all of  your mono images. Then stack with the reference frame still there, but with it unchecked so it is not added to your stack. This is your registered mono image.

If one of you mono images is your best frame, you could reverse the above. For 1 Use the best mono as a ref for you mono and then stack.  For 2) convert the best mono image to color, and use that as a reference to register your color images. Stack with the mono image still as reference, but not checked so it is not included in the stack.

Either way you will have a mono stack and a color stack, which will be registered with respect to each other, so can be then merged in PS or whatever processing software you are using.
Rick
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David Moore avatar
Rick,
Thanks for the clarification. I will try that when I am back home.
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Jacob Heppell avatar
Rick Veregin:
For sure, you can take your best Ha sub and covert to RGB in photoshop. The converted image will be your reference for the color images, the original sub will be the reference for all your mono subs.  Or you can open your best  color image sub exposure in Photoshop then convert and save it as a grayscale image. Use that grayscale image to register the mono images. Use the same color sub to reference all your color images. You don't need to convert a lot of images, just use one good sub exposure as your reference. Either will work, use your best image overall as the reference.

Exactly what I was going to suggest! Although I now use Registar for aligning because it does a better job than DSS.
Well Written
Rodrigo Roesch avatar
Jacob Heppell:
Rick Veregin:
For sure, you can take your best Ha sub and covert to RGB in photoshop. The converted image will be your reference for the color images, the original sub will be the reference for all your mono subs.  Or you can open your best  color image sub exposure in Photoshop then convert and save it as a grayscale image. Use that grayscale image to register the mono images. Use the same color sub to reference all your color images. You don't need to convert a lot of images, just use one good sub exposure as your reference. Either will work, use your best image overall as the reference.

Exactly what I was going to suggest! Although I now use Registar for aligning because it does a better job than DSS.I

I use to use DSS to do that but it was difficult, sometimes would not  register the images. So I calibrated and stacked all the color and Narrow band separated and then open each stack in PS to make sure the pixel density was the same, if not, then you need to resize it otherwise DSS won't register the stacks. Now, I just use Registar which is very powerful and you do not need to resize anything. It would even combine pictures taken with different FL and telescopes.
David Moore avatar
I have been thinking of getting Registar but it is expensive so I have also been looking at PI as you seem to get a lot more for the money but I don't know if it will do what I want regards Mono OSC image aligning. I have noted that it will deal with irregular gradients that are difficult to deal with in Photoshop and also map star colours to true star colours which also would be very useful. I also wonder how it is better than DSS in other respects. I use DSS as it is so quick, easy and straightforward.
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