|
Gary,
If I read correctly, your analysis of the celestial equator is
correct. Looking directly south the celestial equator is at azimuth 90 -
your_latitude.
As I do not have an observatory I drift align each night out. I
learned this from an article on Chuck Vaughn's website:
I drift align using the usual 12mm double cross reticle, but I also use a
3X Barlow so I can see drift early. I like to check for drift every
minute. Most of the time if I can tweak it so there's no noticeable drift
in one minute I'm very close and only a minor tweak or two is needed. As
Chuck states in his article, if you have no drift for 5-10 minutes you are good
to go. The whole process takes me about 30 minutes (but it takes a bit of
practice <g>...don't get discouraged.
Orient your reticle so that the cross hairs are aligned with the compass,
N-S, E-W. You can ignore drift E-W, that is mostly just periodic error in
your mount. The drift N or S is the one that will tell you your mount's
error wrt the true celestial pole. Make your adjustments per Chuck's
article.
Oh, and please don't apologize for asking questions, that's what this list
is for <vbg>.
Frank
----- Original Message -----
Sent: Monday, November 24, 2003 1:31
PM
Subject: [APML]OT-Drift Alignment
Hello All,
I received my new GM-8 Sat. and saw 1st. light with it
last night. My only previous experience is with a LXD55 mount which I
never tried to drift align. I have Jerry's CD book and am trying to
learn how to drift align. I am semi-familiar with celestial
coordinates. I know the meridian goes from Polaris through the
zenith. My question is about the celestial equator. If my latitude
is 37.21 N, will the celestial equator be 90 degrees from that (about 52.79
degrees from the horizon)? If I read the article right it said about 20
degrees above the celestial equator which would put me about 73 degrees from
the horizon, which is approaching the zenith. Is this right or am
I way off for the meridian adjustment? I have no view of the western
horizon so I will need to use the eastern for the second alignment. If I
am right for 73 degrees from the horizon for the meridian, can I just rotate
the mount in RA eastward until it's about 20 degrees from the eastern horizon
for the second drift adjustment? I'm using a refractor with
diagonal. Should I have the diagonal oriented so I am looking straight
down into the reticle? Is the North or South drift true north/south or
as it appears in the eyepiece? I apologize for my ignorance on this
but I want to learn this technique so I can take better pictures without
as much guiding input as I have been having to make with the Meade.
Any guidance and/or suggestions would be GREATLY appreciated.
Thanks!!
Gary
Thaxton, VA
_______________________________________________
Astro-Photo mailing
list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo
|