Re: [APML] OT: Light Pillars in Orion w DSLR

Thanks to everyone for such kind words about the picture. I reworked it but the banding is inherent in the original file. Rats! In random order:

Carlos - my understanding is that they are caused by flat hexagonal crystals of ice floating in the air. If the temp drops quickly, they can form from water vapour. Then, if the air is still, they will tend to float in the same orientation and above light sources, reflect the light back down towards the earth which is why you see the beam. I think!

Chris Cook - I reworked the image and cropped out the worst of the banding but it is in the image - maybe an artefact of the ISO200 error - perhaps the noise is always there and only with so little signal do I see it. Jerry Lodriguss discussed this banding in his pro Nikon DSLR quite awhile ago.

George - I sent the link to APOD - wish me luck! I will send to EPOD if I don't make the cut at APOD. I know most of them like to do this sequentially and not have the same image appear everywhere.

Dominic - I was careful to use integral multiples/divisors of the original in the hopes that I would not inject more problems into the image but the banding is in the original file. The only processing was to crop the image after one curves adjustment to brighten the beams.

Chris Schur - wallpaper! You flatter me! I'm doing that with YOUR images!

Thanks again!

Stuart

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

From: Carlos Milovic F.

To: Discussion of Film Astrophotography

Sent: Monday, March 14, 2005 12:40 AM

Subject: Re: [APML] OT: Light Pillars in Orion w DSLR

Great image! Congratulations.

I liked very much the pillar... What exactly are them? Something like auroras?

Regards,

Carlos Milovic F.
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Astro & Photo - CMF
http://www.astrophoto.vze.com
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Visita "AstroFoto", el foro de astrofotografía en español
http://espanol.groups.yahoo.com/group/astrofoto

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Re: [APML] OT: Light Pillars in Orion w DSLR - reprocessed and withthanks to all!