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batema
06-08-2011, 11:35 PM
I have no new data so am trying to learn how to blend Ha and RGB data so returned to an image I have previously processed and redone.. This is 3 hours of Ha and 1 hour of RGB each channel. HOW RED IS IT!!!!! I do not know if it is too red. Any suggestions greatly appreciated. I layered red on top of HA with 20% red and 80%Ha and then put this into the red channel and then added Green and Blue and processed.

Thanks

Mark

midnight
07-08-2011, 04:07 AM
Mark,

I have just had a go at this and I am finding it is very red too.

Very nice image with nice subtle detail there.

Darrin...

ozstronomer
07-08-2011, 09:33 AM
Mark

Great image, well done:thumbsup:. I found adding Ha quite tricky as well.

This is the site I suggested, http://starizona.com/acb/ccd/software/ps_hargb.aspx.... hope it helps

jjjnettie
07-08-2011, 10:28 AM
It's a fine image! Maybe a touch too red for my liking, but I'm a DSLR girl. :D

multiweb
07-08-2011, 11:51 AM
Loads of great M17 lately and this one is right up there. Great details in the wisps and very natural processing. :thumbsup:

Ross G
07-08-2011, 04:15 PM
A great photo mark.

I really love the deep red.

Thanks.


Ross.

RobF
08-08-2011, 10:40 PM
I love all the detail of the neb and dark material surrounding it Mark. Ha can be fiddley to get the colour balance right. Certainly a bit red, but nonetheless a fantastic image.

gregbradley
09-08-2011, 08:18 AM
A good result there. Perhaps a bit too red. The spine has more blue in it.

Ha+ red together and then G and B added leaves you no control.

There are several ways to add Ha. I like the Ha as a lighten blend mode with the green and blue channel deleted leaving only the red.

Lighten blend means only those pixels that are lighter than the layers above will show through.

So your curve at 45 degree straight line is neutral and if you push up the curve you start adding red.

You also make a duplicate layer before you delete the green and blue and this time delete the red and green channels giving blue. Add about 10% of this to the image and it adds the Hbeta colour to the nebula which is bluish. Also in lighten mode for the layer. Now you can control these Ha layers with curves.

There are other methods but I think they largely add up to the same thing in the end. Its which one gives you the most control and the most pleasing result.

Adding Ha to the luminance channel is the tricky bit. Not entirely needed unless you are doing HaRGB. Ha washes out the RGB badly and gives the dreaded salmon colour. A small amount may help the image but in small doses usually.

Perhaps that Arizona site technique for adding Ha as luminance may be helpful there.

Greg.

batema
09-08-2011, 06:15 PM
Thank you all for the comments. There is always something to learn in this hobby.

Mark

Geoff45
09-08-2011, 06:44 PM
I like it. I think the red is like it really is.
Geoff

batema
09-08-2011, 08:08 PM
Adjusted the colour channels. Less red and more blue.

Mark

strongmanmike
10-08-2011, 12:11 PM
Ahh yes, lovely repro, rich colour :thumbsup:... the original was good anyway

Mike

gregbradley
10-08-2011, 01:51 PM
Very nice Mark.

Greg.

marco
10-08-2011, 07:50 PM
Much better the second one :) A very beautiful image of this nebula!

Clear Skies
Marco