Re: [APML] NGC 6946

Hi Tony,

Overall a very nice image. I think you may have removed too much

green. The image IMO is green deficient. One way to get rid of green

halos would be to first select all stars. You can do this by going to

color range and choosing "highlights" or by clicking on the stars.

Then go to "modify" then "expand" and try maybe one or two pixels.

This will incorporate the halos in the selection. Then you can just

do a gaussian blur on the green channel. Another way is to select the

stars plus halos and then go to "distort" (under filters) then go to "spherize"

and shrink the star in only the green channel.

BTW I thought your previous image of NGC 6946 was excellent. Why

did you redo it? Here's my version done last year at

http://www.robgendlerastropics.com/6946LRGB.html

Rob Gendler
Email: robgendler@att.net
Web site: http://www.robgendlerastropics.com/

----- Original Message -----

From: Tony Hallas

To: Discussion of Film Astrophotography

Sent: Wednesday, July 09, 2003 12:19 PM

Subject: Re: [APML] NGC 6946

Hello all,

    I better post this before you read somewhere in some obscure headline "Astrophotographer commits suicide over astro image..."

    Bad seeing makes it almost impossible to make a CCD work ... they're just too sensitive ... but I did what I could to make this fly... the worst thing that happened was really bad seeing during the green exposure... all the stars bloated in relation to the rest of the colors, so that when the RGB was combined, there were nice green rings around the stars ... wonderful! If anyone knows some way to deal with that, I would sure like to know. I had to fix this the hard way ... star by star ... I must be nuts.

     http://www.astrophoto.com/NGC6946.htm

    Comments always welcome...

         Tony

_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo