From: Alan Friedman <alan@greatarrow.com>

Date: January 23, 2007 10:56:31 AM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Saturn with 4 moons

Hi Milton

On Jan 22, 2007, at 8:07 PM, Milton Aupperle wrote:

Just out of curiosity, how many frames of video are you recording per stream and how many are you using for stacking?

I used four separate streams for the luminance part of this image captured over a span of about 15 minutes. I was shooting without filtration at about f40, capturing 1200 frames in each stream at 33ms shutter/30fps. I used a total of 700 frames from the four streams - about 15%. I looked to see if there were any disturbances showing in the cloud belts - none were seen, so I averaged all the data together. Of course the fast rotation of saturn would require much shorter windows of capture to record storm activity. The RGB data is captured at f30 66ms shutter and 15fps, then resized and rotated to fit the luminance image in Photoshop.

I was shooting about 2000 frames and then letting Astro IIDC pick the top 100 frames for stacking. Even doing it manually, I don't disagree with what Astro IIDC picks (i can have it dump out the frames manually it selected).

I processed several of the streams in Astro IIDC and had the same impression - I couldn't tell the difference between the stacks made in Astro IIDC and those made from hand selection in KIS. I would have prepared this image fully in Astro IIDC, but I worked on this on my home computer with its bright LCD monitor rather than my laptop.  I haven't purchased a second copy of the program yet - something I need to remember to do!

best -

Alan