Author Topic: vdb142 - narrowband - have a try  (Read 13550 times)

Offline starhopper

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Re: vdb142 - narrowband - have a try
« Reply #30 on: 2012 November 16 09:04:00 »
Hello M.
If somebody asks me to share the method, I'll be embarrassed
That's what I do. Can you provide a screen copy of your personel pixelmath formula?

I have successfully made bicolor Images with Cannistras workflow in PS.

Cheers Thomas
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Offline mcbbcn

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Re: vdb142 - narrowband - have a try
« Reply #31 on: 2012 November 16 13:55:18 »
Well, I guess it was meant to happen.  Now, I'm embarrassed...  :-[

...but I'll do more than put the pixelmath values and I'll attach an RTF doc that contains the flow and the pixelmath values.

Just to give you some background on how I went about it.  I took a regular daylight image in PS, and I applied Cannistra's color balance.  Then, at the same time, I opened Pixinsight, and I started to play around with a Pixelmath formula that Juan just shared with me to control shadows, midtones & highlights.  So, when the Pixinsight image look close to the PS image, I annotated the values.

Then Cannistra uses blending PS modes, and as Gerald has a great page with the PS Blending modes formulas for Pixinsight & other programs, it was relatively easy to extrapolate some of the blending modes in Pixinsight using Pixelmath.

As you will see in the instructions, I had to do a bit of tweaking with Curves Transformation, but in the end, it came out pretty good color-mapping wise for an Ha & OIII bicolor combination.

My documentation is not elegant in any shape or form, and the Pixelmath formulas, some...I hard-coded the values, and some others I used variables...I'm sure it can be done in a much better way.

I spent quite a lot of hours doing trial & error to get the as close color balance as I could, but if you find a better way to do it, please post the results.  In the end, color mapping is like food & flavors, everybody is going to be right.  :)

See link to download the document:

Enjoy it!