Re: [APML] OT: Collection of tricolor emission line images

Thanks for the nice comments, Ray. Yes, I prefer the medium format lenses because of the additional back focus distance. I haven't measured it super accurately but it is at least 3" compared with about 2" for a typical 35mm lens. Because I want to use a filter wheel and a robotic focuser (FLI DF2 or PDF), I must have the extra back focus of the medium format lens.

The setup works very well and is both simple and cost effective.

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

From: Ray Butler

To: Discussion of Film Astrophotography

Sent: Wednesday, June 22, 2005 2:57 AM

Subject: Re: [APML] OT: Collection of tricolor emission line images

Richard, those are fantastic images. They really show familiar objects in a whole new light (no pun intended!).

I especially like the wider field ones taken with the Pentax 6x7 lens. I presume you chose a MF lens because of its long flange-to-focal plane distance, giving you enough room for your filter wheel etc?

Ray

Richard Crisp wrote:
I assembled this collection of some of my favorite tricolor emission line images to help folks find these on my website. I took these over the past two years.

With the article I wrote in the Aug S&T on the topic, there has been a bit of interest in seeing more of these images and more than one person has told me they are sort of hard to find on my website so here's a simple collection of some of the highlights.

http://www.narrowbandimaging.com/Tricolor_page.htm
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo
  
-- 
Dr. Ray Butler
Lecturer, Physics Department & Computational Astrophysics Laboratory,
National University of Ireland - Galway, 
University Road, Galway, Ireland. 
Web: www.nuigalway.ie/physics/ 	Email: ray.butler-AT-nuigalway.ie 
Tel: +353-91-493788 		FAX: +353-91-494584
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo