Author Topic: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?  (Read 5246 times)

Offline topboxman

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Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« on: 2013 March 29 17:06:48 »
Which "Adding Ha to RGB" script is better?

SilverCup or HaRVB-AIP found in RC5?

I have used SilverCup's script with pretty good success in version 1.7. I had a heck of a time putting this script in RC5 but it works.

Anyone can give tips on how to use HaRVB-AIP script?

I do not understand the following HaRVB-AIP parameters:

Ha % in R Channel: defaults to 33%
R % in Ha Channel: defaults to 33%
Noise It: defaults to 3

If I use defaults of 33% for both, it looks strange.

If I use 100% for both, it looks better and closer to SilverCup's script.


So, which script do you like better.

Thanks,
Peter
« Last Edit: 2013 March 30 17:46:55 by topboxman »

Offline topboxman

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Re: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« Reply #1 on: 2013 March 30 20:02:48 »
No one capture Ha and adds Ha to RGB images? I find this method much better than LRGB under heavy light pollution. Capturing images with Luminance under heavy light pollution is extremely difficult. Ha filter does an awesome job of blocking light pollution and I can image at 30 minutes sub-exposures.

Here is a sample of my most recent image of M82 Cigar Galaxy using Ha and RGB. This uses SilverCup's script for adding Ha to RGB.

http://peternagy.smugmug.com/Telescopes/Galaxies/15823423_dS2M3V#!i=2430678873&k=TsVxrFw&lb=1&s=A

Peter

Offline MikeWiles

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Re: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« Reply #2 on: 2013 April 01 10:04:01 »
I'm right there with you Peter.  Much of what I've done over the last year has been shooting narrowband frames for long exposures from my light polluted backyard, and then shooting the matching RGB from a dark site.  Like you,  I'm always looking for a better way to blend the Ha data into the final product....so I don't have any real answers for you either.

Mike

Offline topboxman

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Re: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« Reply #3 on: 2013 April 01 10:20:11 »
Hi Mike,

I find SilverCup's method very good. I was just curious about HaRVB-AIP script that's part of RC5. All I am asking is which is the preferred method and how to use HaRVB-AIP script. My understanding from other posts that SilverCup's "Adding Ha to RGB" script was supposed to be part of version 1.8 but I cannot find it.

After I captured LRGB and Ha of M82 from my light polluted backyard, I tried many different processing methods to get the best results. Ha captured the red star burst at the core very nicely but Luminance did not. When I applied Luminance to (HaR)GB, it made it worse because it removed most of the colorful red star burst at the core. So I ended up extracting the Luminance from (HaR)GB and processed this Luminance as a pseudo-L and then combined psuedo-L with (HaR)GB and got pretty decent result.

I am too lazy to go to a dark site.

Peter

Offline pfile

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Re: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« Reply #4 on: 2013 April 01 18:04:21 »
what i did on m82 was to add the Ha to both the luminance and the red, by writing a pixelmath expression that tried to average in the Ha to each channel only where the Ha signal exceeded some threshhold. that way when i did LRGB the L would "be there" to support the red channel.

worked okay i suppose.

Offline Philippe B.

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Re: Adding Ha to RGB: SilverCup's method or HaRVB-AIP?
« Reply #5 on: 2013 April 02 00:29:26 »
I only use HaRGB script.
You have to choose which % of Ha you will inject in the R channel
You have also to choose which % of red you will add to the Ha luminance

I prefere doing my own luminance by a alternate method. Or I use SHO script to do this