From: "Brian" <bgshelton62@yahoo.com>

Date: January 25, 2010 2:27:50 PM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: Cloudy Mars from Cloudy Buffalo

Hi Alan,

Very nice image indeed.

Thanks for sharing.

Rgds,

Brian

_ 

--- In Astro_IIDC@yahoogroups.com, Alan Friedman <alan@...> wrote:

Thanks for the comments!

Milton, these are orographic clouds associated with the major volcanoes. This image was made with the Scorpion's 800x600 setting that we've been discussing. I'm not quite positive on the exact focal length. I used the Baader FFC with my 10" mak - normally this would bring a focal length increase of 3x, but the image scale was very small with the pixel binning so I added an extension tube. I'm guessing the setting was approx f50 or a little more... perhaps a 13000 mm FL. The exposure for these movies was 33ms with a brightness setting between 800-900 for IR, R and G, over 900 for blue. 

The color filter breakout images show the actual size of the planet in the movies. Astro IIDC really liked the contrast and smoothness of the smaller planetary disks - it did a very good job with frame selection and stacking. I chose about 450 frames from 1500 in each of the movies and used four MAP regions each time. This helped to get the best sharpness in the albedo markings.

best,

Alan

On Jan 24, 2010, at 7:12 PM, Milton Aupperle wrote:

Hi Alan;

Very nice image.

It's interesting to see that the bluish clouds are over most of the 

larger volcanoes (assuming I figured out the correct local date time).

What focal length and exposure times were you using?

TTYL..

Milton Aupperle

On 24-Jan-10, at 4:49 PM, Alan Friedman wrote:

Hi all,

Winter has afforded only two shots at Mars this winter, both with 

the same face facing Buffalo:

http://www.avertedimagination.com/img_pages/mars_20100122.html

Seeing fair - about 5/10, transparency good, gusty winds.

I used this opportunity to try several cameras and camera 

settings... this is the first I've processed, using the PGR Scorpion 

camera (1600x1200) at its 800x600 setting. Image scale is smaller 

than I'm used to with the pixel binning enabled in the camera.

clear skies and best wishes,

Alan