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Hagar
02-10-2010, 07:28 PM
Without being too controversial I have posted another image which is a combination of standard RGB and a Ha blended with a Luminance channel

I did have some horrid reflections came through on the G,B and Lum channels which I will have to look into further.

I have included a full frame which shows the reflection in its blue glory. The crop just removes the corners and this reflection and looks a lot better. Stars are still a bit of a worry but even the RGB stars were nothing great either.

Thanks for looking.

DavidU
02-10-2010, 07:50 PM
Well captured reflection nebulae. You don't often see that.
Cheers Doug.

Alchemy
02-10-2010, 08:46 PM
Comtoversy controversy controversy, dougs now painting in reflection nebs......

Yes you will have to look into the cause of that reflection it's a beauty.

Hagar
04-10-2010, 09:53 AM
Thanks Clive and Dave. Looks like this image is not up to scratch or everyone is scared to post a reply.

Ah well.

strongmanmike
04-10-2010, 05:11 PM
It's..:scared2:.ok..:scared:..I guess:help:...some good detail..:scared3:

Seriously Dougie, tis not yer best me hearty but me thinks ye know what ye need to be doin. The crop looks pretty ok though :thumbsup:

desler
04-10-2010, 06:36 PM
Scared, not really, just waiting for the more learned to have their say.

Although, I personally think the detail in the bottom of the paw is amazing, love to see that as a close up. Keep posting the blends so I can pick your brains.......


Darren

Hagar
05-10-2010, 12:21 PM
Thanks Mike. Not my worst either so a little miffed at the lack of comments. There is some glaring faults in the image but some awaited bits will hopefully fix things like focuser droop and field flattening. I thought maybe the last image posted and the comments may have scared everyone off.




Thanks Darren, Not much to pick these days. I wish I could blame it on the grog but I now think it's old timers.

gregbradley
05-10-2010, 07:51 PM
You've obviously got some nice data there Doug but perhaps the technique of combining Ha and RGB is the weak spot. It is a topic of different approaches and viewpoints and one of those things where you work out a style you like after trying a few different ways.

Using lighten mode is one way as it preserves star colours but it is a weak way of blending usually. Multiple layers and screen mode can help, assigning some Ha to a blue channel and 15-20% helps add the H-beta colour your Ha most likely picked up. Sometimes adding a Ha final layer as luminance but only a tad 10-15%) will control the too red factor and pull the saturation down a bit and add a bit of brightness.

Rob Gendler's approach of Ha and Luminance combining is very good for a starter.

But then I am not sure if you shot any luminance for this one.

By the way some of these objects are just plain red and are not necessarily the most colourful object around.

If you don't use lighten mode you may best do it with a masked layer and rub only the areas of neb through and not the stars otherwise you'll get too much red in your stars. Of course you can select out your stars and keep them RGB and add them back in later as well. There are many ways of skinning a cat in Photoshop.

Greg.