From: "jimchung2338" <jim_chung@sunshine.net>

Date: February 20, 2010 7:49:24 AM MST

To: Astro_IIDC@yahoogroups.com

Subject: Mars with a 74" reflector!!!!!!!

Ok, now that I've got you're attention I don't want any of you to have unreasonable expectations.

Last night, I managed to do some Mars imaging with 74" reflector at the David Dunlap Obseratory, just north of Toronto.  It's about 15 miles away from downtown.  It was established in 1935 and at the time was the second largest scope in the world, after Mt. Wilson. The mirror was made from the same batch of glass Corning used to pour the Palomar miror!  As a result of increasing development, the University of Toronto sold the land at great profit last year and the buildings and scope are currently being maintained by the Royal Astronomical Society of Canada/Toronto center.  Hopefully what's left will be declared and protected as a national historic site.  

Here's some observatory images:

http://tech.groups.yahoo.com/group/Astro_IIDC/files/Other/DDOmontage.jpg

And here's Mars:

http://tech.groups.yahoo.com/group/Astro_IIDC/files/PlanetaryMarsDDO.jpg

Seeing was only average but the massive focal length used exacerbated this.  The first image is with an AstroPhysics focal reducer, and the second at native focal length. I was able to easily shoot at 30 fps and at low gains.  The reflector is currently setup in cassegrain mode.  It is possible to change it to Newtonian mode (no small feat) but the large drop in focal length would make it a better planetary imaging vehicle.  

Anyway, it was an experience!