GEM Alignment Jig, variations on a theme

[LAW (Murphy)]

Hey all, I really liked this idea for a simple alignment jig (http://www.iceinspace.com.au/63-499-0-0-1-0.html), but I noticed that it didn't account for the azimuth adjustment within the mount and as a result my first attempt at alignment was woeful , no fault of the jig, I think it's a brilliant idea, I just overlooked a simple source of error. So I came up with an addendum...

I wanted something that was going to be practically portable, as simple as the original idea and allow for Azimuth adjustment without relying on eyeball corrections.

I lay a 4' piece of timber North-South using the 'true north' function on my iphone.

http://i735.photobucket.com/albums/w...S/IMG_2453.jpg

Then I bought a laser line from my local hardware shop for $50, it has a magnetic base and two perpendicular flat sides. So just hold it against a flat surface which runs parallel to the declination axis (in this case, the latitude dial).

http://i735.photobucket.com/albums/w...S/IMG_2450.jpg

So all I have to do now is shuffle the mount around until the laser line runs down the edge of the wood.

http://i735.photobucket.com/albums/w...S/IMG_2452.jpg

Hope that helps some more n00bs, dark skies everyone

[silv (Annette)]

right, you are.
the "azimuth adjustment within the mount". man... and nobody ever mentions this...!
I'm glad you made a thread for it and a solution, too.

thanks!

[Poita (Peter)]

Nice idea.

Wouldn't you just set the azimuth adjustment knobs to their central position before you start? Or isn't the mount marked to be able to do that?

[LAW (Murphy)]

Yeah, mine isn't marked. But I'd rather eliminate as many sources of error as possible anyway, the only problem is its only as accurate as the compass.