Re: [APML] B86 and Red Halos

[Matt BenDaniel <matt@starmatt.com>]

At 04:22 PM 5/18/2002 +0200, Mario Cogo wrote:
>Matt,
>
>Very good image.

Thanks.

>This is a beautiful object, and your shot shows more details than mine,
>in particular inside the dark region of B86.
>The difference from AP130 with 67 and Traveler with 35mm is clearly visible.

It's not just that. Compare the histograms of both our images. Yours is clipped significantly on the top end of the red, the bottom of the green, and both ends of the blue. If your image were processed to be unclipped, it would show better resolution, just about as good as with a 130.

>I also noticed in my image some slightly red halos around the bright red
>stars.
>Yes, I known that it's a cropped area from the original Sagittarius Star
>Cloud frame, but does anybody have any tips or Photoshop techniques
>to reduce only the red halos?

I like stars to show colored fringes. I curved this image to soften the stars and bring out their colors. It may be that I went too heavy on the red across the entire image.

Anyway, you can use Photoshop magic wand (tolerance 20) to select the colors you don't like and then create a hue/saturation layer to desaturate the reds by 30% or so.


>Thanks
>Ciao
>
>Mario Cogo
>e-mail : cogom@aruba.it
>My Web Site : www.intersoft.it/galaxlux
>
>
>
>----- Original Message -----
>From: Matt BenDaniel <matt@starmatt.com>
>To: <astro-photo@seds.org>
>Sent: Saturday, May 18, 2002 5:36 AM
>Subject: [APML] B86
>
>
>> http://world.std.com/~mattb/gallery/astro/b86.html
>>
>> Here's a view of NGC 6520 and Barnard 86. I was inspired by Mario Cogo's
>excellent shot of the same subject.
>>
>> This B86 image was cropped from a Sagittarius Star Cloud image, which
>gives you an idea of how much detail is there.
>> http://world.std.com/~mattb/gallery/astro/sag_cloud.html
>>
>> Comments welcome.
>> --
>> Matt BenDaniel
>> matt@starmatt.com
>> http://starmatt.com


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