Re: [APML] M 13

Hi Tony.

Some comments and observations. The image seems to have a very good histogram yet the stars are very subdued and understated. Did you try pushing the levels and curves more to bring out more "snap" (contrast) without burning out individual stars. I think this image can be processed more aggressively without losing any of the data you worked to preserve. Also, have you tried any of the anti bleeding software that's available to fix the stars with pixel bleed?

Please tell us more about the processing you used and how it can be applied to film images, if that is possible.

Clear skies.

Jim

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

From: Tony Hallas

To: Discussion of Film Astrophotography

Sent: Thursday, June 12, 2003 9:50 PM

Subject: Re: [APML] M 13

Hello,

    With the moon up and my CCD back in my sweaty little palms I decided to see how far out M13 goes... I had some time to reflect on the strengths of the CCD medium... IMHO the most significant thing is the ability to record 16 bit data right out of the sky. If the data is preserved in the reduction process, amazing detail will result (hopefully).

     So... this is a series of 10 minute exposures (7) combined with Sigma processing and utilizing a 30 exposure dark frame also processed with Sigma... then into PS as a 16 bit Tiff and the visual data opened using curves. It's in B&W ... color will follow.

    At first glance it looks like Omega Centuri... but what you are seeing is well beyond the "normal" boundaries of M 13 ... and I have evened out the luminance considerably... the core vs. outer area is probably a 1 to 100 brightness ratio ... the beauty of 16 bit data.

     http://www.astrophoto.com/M13deep.jpg

     Have a good one,

           Tony

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