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p1taylor
01-02-2011, 10:30 AM
Hi All,

Hope this is not a silly question, I wont to ues PHD to polar align my rcx but I cannot sort out which is 0 degrees on meridian, I always thought it was at north arisen, but what I was reading said it is at zenith, hop someone can tell which is right.

peter

Octane
01-02-2011, 11:47 AM
Peter,

Make sure your RA axis is horizontal (or close to it), and, point your scope at 0 degrees DEC. That is, about 90 degrees (perpendicular) to the pole. There, you will find the meridian.

You use a star within 20 degrees (east or west) of the meridian to make adjustments to your azimuth.

Then, simply put your RA axis down so that the scope points within 20 degrees of the horizon on either the eastern or western horizon. You find a star here, to make adjustments to altitude.

Hope this helps.

H

GrampianStars
01-02-2011, 11:58 AM
G'day Pete
Your in the North :question:
If Your using a Wedge.

level fork arms horizontal with spirit level and lock RA
Point OTA perpendicular with fork arms.
(i.e. tube inline with forks.finder on bottom.)
set DEC circles to "O"
Polaris should be in field of view somewhere (26mm)
To centre Polaris in the crosshair, If it’s off, Manually move the mount in latitude (altitude) knob on back, and azimuth knobs on side, to center Polaris.
" Then rotate the RA setting circle till it reads 2 hours 31 minutes and the Dec circle reads +89 degrees 15 minutes."
These are the coordinates of Polaris and the Pole Star should still be centered in the finder’s crosshairs.

Now all you need to do is use AutoStar until the RA until it reads "0" and your done :thumbsup:

should take 10 minutes tops

p1taylor
02-02-2011, 12:57 AM
Hi Rob and H,

Tanks for info on alignment yes I am north and on a wedge, think I must have worded my question wrong, what I want to now is where 0 and 90 degrees are on the astronomical meridian.

peter

GrampianStars
02-02-2011, 06:33 AM
Good luck with it Pete :thumbsup:

"0" deg. RA on the meridian is the same as for polar align. (see previous post)
"90" deg. DEC on the meridian is straight up (spirit level goes across the front of the scope over the corrector)