From: Milton Aupperle <milton@outcastsoft.com>
Date: September 23, 2005 7:48:36 PM MDT
To: Astro_IIDC@yahoogroups.com
Subject: Re: [Astro_IIDC] Mars from Los Angeles
Hi Tim;
On 23-Sep-05, at 4:55 PM, Tim wrote:
Hi folks:
I've uploaded my first Mars image acquired with Astro IIDC and my Aplux Firewire
webcam, to the "files/planets" section of the website.
Nice shot considering seeing was average to below average.
Seeing was below average, with very brief moments of clarity (fast turbulence). I used an
orange-tube C-8 with a "shorty" 2x barlow on a Takahashi EM-10 GEM for this image.
Signal to noise was better at 66.67ms exposures than at 33.33ms, so the frame rate was
only 15/second.
Higher gain levels == higher noise == worse S/N.
I used Astro IIDC to acquire 4000-frame quicktime videos, and to automatically align and
stack the best ~600 frames. All other processing and annotation was done in Canvas X.
Note: prior to this session with the Aplux camera, I had been using a 16ft firewire cable I
purchased at Fry's Electronics (can't remember the brand cable). I was having problems
with stacking the frames acquired with that setup. So, when the problems "went away"
when I used a 6' Apple Firewire cable, I decided I must be losing power or data through the
longer cable.
Poor shielding can cause problems in long FW cables, especially if they were cheaply made (but you can't tell it's "cheap" until you cut it open). Generally stick with 10' / 3.3 meter cables or less.
I have one 4.5 meter cable, it is thick almost coaxial cable thick and has those EM suppressing Ferrite beads on both end near the business ends.
TTYL..
Milton J. Aupperle
President
ASC - Aupperle Services and Contracting
Mac Software (Drivers, Components and Application) Specialist
#1005 - 815 14th Avenue. S.W.
Calgary Alberta Canada T2R0N5
1-(403)-229-9456
milton@outcastsoft.com
www.outcastsoft.com