Author Topic: How to add Ha or OIII to LRGB data  (Read 2850 times)

Offline Dimitris Platis

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How to add Ha or OIII to LRGB data
« on: 2014 June 11 23:07:15 »
I have seen a few methods for adding narrowband data to broadband data...some with successful results, others with less than successful.
Never could find a successful well documented method for doing that.....in the sense that.....I have for example perused through Vincent Paris' tutorial of adding Ha to Galaxies (both the video and the long tutorial about continuum maps(http://pixinsight.com/tutorials/narrowband/)) but I cant make these things work. They seem to work on idealized versions of fits and should one wish to adjust the method to fit it doesnt seem to work (easily at least or even with some effort). Let me give u some examples of some issues...

Should the Ha image contain almost same number of stars as the broadband Red image (due to example overexposure) that seems to create some problems in creating reddish stars, or reddish background. Also, a continuum map in these cases is almost impossible to obtain....should I Rescale or not?


Could perhaps some explain the correct strategy for doing that (No script methods please). I would appreciate if we get the mere basics of what Vincent is trying to accomplish.
I would certainly appreciate any help!

Thanks people...

Offline jkmorse

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Re: How to add Ha or OIII to LRGB data
« Reply #1 on: 2014 June 13 13:19:58 »
Dimitris,

Attached is my Cribsheet that describes a couple of different methods for adding Ha data to an RGB image.  The first method where I go into detail works well for me.

Jim
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Offline Harry page

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Offline Dimitris Platis

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Re: How to add Ha or OIII to LRGB data
« Reply #3 on: 2014 June 16 03:54:15 »
Thanks everybody...
I have seen Harry's videos...but I am really trying to understand the idea behind the algorithms....