Another adding HA to RGB

[ashworthacca]

I have read the other threads on this bit I'm unsure on a particular area. I have a RGB Image of M81 and M82 that I have processed and also cropped.

Last night I gave my new HA filter a run out and grabbed 8 x 900 secs plus darks and flats of the same subject but I'm sure that framing will be different to the RGB image.

How do I add the HA to the RGB in this circumstance baring in mind the RGB is cropped and the HA image will be a slightly different framing. They were shot with same camera and scope.

I have photoshop and also pixinsight.

Thanks for any pointers guys.

[ollypenrice]

It can be done in Ps but it is an awful palaver and I have forgotten how to do it. I daresay PI can do it as well.

I use Registar, one of the best programmes there is and a (fairly expensive) essential in my imaging. Google Registar, Auriga Imaging.

In a couple of clicks you register the Ha to the RGB then use 'crop and pad' to ensure that when you open them in Ps they will sit perfectly aligned.

As a ganeral rule I avoid cropping until the very end because I often want to reopen a linear image and rework it to add as a layer to what I have already done. Instead of cropping I use a rectangular marquee to eliminate edge artifacts from the histogram. If you don't do this it is hard to make sense of the graph.

Olly

[ashworthacca]

Thanks Olly, I thought Registar might be recommended but I was previously put off by the price. If it can't easily be done with PS or Pixinsight I may have to bite the bullet and buy it!

Thanks again Olly

[Whippy]

If it's been taken with the same setup then registar isn't really needed IMO, you can rotate and crop as necessary in photoshop. Have a look here for adding HA to RGB: http://stargazerslounge.com/imaging-discussion/135054-adding-ha-data-lrgb-image.html .

Tony..

[ashworthacca]

Thanks Tony, I'll take a look

[harry page]

Hi

I have been playing with a new way of using Ha in pixinsight and it works very well ( so far )

I will be doing a video this week

Harry

[ashworthacca]

Whooo, I'll look out for that Harry!!

[martin_h]

Cant you re-register the uncropped stacks with the Ha stack? Thats what I do, I know it means reprocessing the RGB, but you've done it once so it shouldnt take to long. Once they are registerd against each other you can crop and it wont make

any difference to the alignment - you may have to nudge it a bit but it wont be far out.

[ashworthacca]

Cant you re-register the uncropped stacks with the Ha stack? Thats what I do, I know it means reprocessing the RGB, but you've done it once so it shouldnt take to long. Once they are registerd against each other you can crop and it wont make

any difference to the alignment - you may have to nudge it a bit but it wont be far out.

Of course, I never thought of that:o

Thanks Martin, another weapon to try.

[harry page]

Hi

Here is a video I did showing how to add Ha to a galaxy using Pixinsight

http://www.harrysastroshed.com/Hagalaxy.html

Hope its of use

Harry

[ashworthacca]

Thanks Harry, I'll take a look