From: Ray Byrne <ray@in4media.co.uk>
Date: April 12, 2007 12:15:23 PM MDT
To: Astro_IIDC@yahoogroups.com
Subject: More from Ray
Hi Doug,
I'd also like to add that AstroIIDC for what ever use is the Bee's-Knees. A really great integrated imaging software that alone makes it worth changing to a Firewire camera. It's 21st century stuff!, easy to use and very powerful I'm still finding great stuff as I get to know it better but was easy to use first night.
On 12 Apr 2007, at 15:27, Doug wrote:
Hello Everyone - I would like to start solar imaging in a serious way (up until now I have
just been capturing video with Meade EEP and A to D converter). I just joined this group
because I plan to use Astro IIDC and I'm now shopping for a suitable firewire webcam. I've
searched this and lots of other forums, checked out manufacturer's sites and camera
specs and now I've reached the analysis paralysis stage - I'd be grateful for some help at
this point. Sorry if the post ends up a bit long....
I am reasonably familiar with digital imaging and processing because aside from being an
avid amateur photographer, I use cooled CCDs for low-light microscopy in my day job. I
should qualify the latter; I direct a lab where others far more knowledgeable actually do
the hands on work but I make the purchasing decisons and criticise the output, LOL.
In any event, my sole astro-imaging interest at the moment is H-alpha (and CaK to lesser
extent). The camera I purchase will be dedicated to this task so I'm looking for the "best"
camera for the intended application, not necessarily the most versatile. I will be using
primarily a Solarscope SF70 (70 mm) F-P etalon attached to a TV 76 refractor. I would also
prefer to stick with a non-tracking alt-az mount for the time being unless someone tells
me this is definitely not the way to go (I'm assuming image shift over a few second capture
period can be handled by registration/stacking software). Finally, I am very interested in
being able to image the entire disc with little (or possibly) no stitching. BTW, the SF70
gives remarkable on-band performance across the entire disc without any detectable
"sweet spot".
I'm thinking larger format chips (1/2-3/4") would suit my needs best and with a
telecompressor would give me a big chunk of the disc through the TV76 (480 mm w/o
reduction). However, I don't know how to gauge whether the frame rates are good
enough. 15 fps seems pretty fast to me for an application where I'm not really light limited
(i.e., solar) but maybe I'm wrong about this? I know capturing even 15 fps full-res with the
largest webcam chips would tax the cpu but don't have a feel for how a current Macbook
(pro?) running ASTRO IIDC would handle the data stream (via firewire).
As for cameras, I've got the following short list - monochrome of course: DMK41 series,
PGR Flea2 (wondering about Optronics but haven't priced yet) or waiting for one of Paolo
Lazzorotti's cameras, which seem promising at the specs currently listed. I take it
Lumenera involves too many headaches for use with a Mac?? Should I not be so wedded to
the idea of larger format at the expense of fps? I'm not so concerned about resolution but
my feeling is that if the cpu can handle the data then why not higher-res?
I wish I could grab one of the >$15k cooled large chip CCDs on my microscopes outside
for a try but alas, I cannot...
thanks for any advice or suggestions,
Doug
ATB
Ray Byrne
in4media | graphic and website DESIGN
T: 01793 435704