From: Mark Gaffney <markgaffney@mac.com>
Date: September 6, 2008 10:34:34 PM MDT
To: Astro_IIDC@yahoogroups.com
Subject: Re: [Astro_IIDC] necessity of drift aligning....
Hi Milton, Glad you had a good holiday! That`s good news about the need for PA. I`m leaving the scope out under tarps now (we had quite a downpour 2 days ago) & apart from the tripod legs sitting in puddles of water for a time it seems to have weathered it OK. The longer FL on the new OTA is to make things like Jupiter & Saturn to begin with, larger in size & more resolved. The 10" had a FL of only 1200mm-smaller than my 4"- besides I was finding it difficult to focus properly for photos for one thing & Jupiter for instance was smaller in relative size than the 4". Using my 2x barlow didn`t help much either in terms of resolution. I can use the CG-5 mount for both big scopes now. I find there`s a lot of fussing setting up the camera & finding things with it which I can do without at present when concentrating on & learning DA. Are you familiar with the work of Damien Peach; here`s a link to his site;
http://www.damianpeach.com/c925review.htm
I didn`t have any problems putting things in the C9.25`s FOV night before last. One of the problems with the C10-NGT was it`s unwieldiness- I was always bumping my head on it & had to use a stepladder to look through the eyepiece quite often... I`m sure it`ll still have it`s uses as a "light bucket"! By the way I think I`ll follow your lead & get a Celestron radial guider in the for-see-able future. Mark.
On 07/09/2008, at 11:47 AM, Milton Aupperle wrote:
Mark;
On 6-Sep-08, at 4:21 PM, Mark Gaffney wrote:
Hi Milton, would a bout of drift aligning be necessary each time the scope is used
Nope
or only
when performing more difficult proceedures such as guiding & photography of DSOs?
You only need to do drift or polar alignment after you have moving the scope areound. If it's stationary and is not re-oriented (i.e. hauled into a garage etc.) before being used, then it should be a one time thing. Do it right once, and that's all you need to do.
I`ve
made several attempts at drift aligning since writing last, all using a reticle eyepiece as the
camera seems one too many factors to control at the same time.
I really don't understand why it would be such a difficult procedure or why the camera makes things worse, unless of course your mount is having either mechanical or weight issues (i.e. loading too big a scope on a mount is asking for trouble).
No doubt I`ll try it
eventually! I have a new C9.25 XLT OTA now but have had to postpone buying the colour Flea
2 because of the added expense of this OTA over the C8.
I really don't see how a C9.25 is going to help. It has an even longer focal length than a C8 or your 10" does, which means it's even more sensitive to misalignment than before and will require very precise pointing to put a target in the Field of View.
Hope the weather cleared up for
your experiments with the Grasshopper at the dark sky site! Mark.
I got skunked. I had one moderately good night in 3 weeks which was when capture Luma for M101 and M27. Then the weather went to crap, either raining for days on end or being clear during the day and clouding over at sunset for all night. At least I got some golf in and spent time with the immediate family.
Oh well maybe this winter will be better.
TTYL..
Milton J. Aupperle
President
ASC - Aupperle Services and Contracting
Mac Software (Drivers, Components and Application) Specialist
#916, 742 Kingsmere Crescent S.W.
Calgary Alberta T2V2H8
1-(403)-453-1624