PDA

View Full Version here: : Polar Alignment


graway
30-05-2010, 03:31 PM
Thanks again to those who helped my last{first ever} question
My next problem is that I can't see the SCP from my spot due
to some large trees.
Is there a way to roughly align the scopes scales.Not sure if
this works or not???,

Regards Graway

peter_4059
30-05-2010, 03:47 PM
Graham,

I'm in the same position at home. I use a compass to get it about right then drift align. You can get a digital inclinometer from Bunnings to get the altitude close if you want although this rarely needs to be adjusted once it's set for your location if you level the tripod properly each time. There's a good article in the resources section of the forum that describes how to drift align.

Peter

mithrandir
30-05-2010, 04:20 PM
You don't have to use the SCP to align. Roughly point the mount south (a compass helps, but don't take what it says as the absolute truth). Level the tripod (don't trust any builtin level - a pocket size torpedo level is handy). Set the RA axis to your latitude. Slew to the coords of something you can see. If you are nowhere near, turn the tripod and fix the level. If you are close, use the azimuth adjustment. Repeat the slew/adjust for a couple more stars. Try not to change the RA alignment until you have the azimuth close.

Once you get your tripod correctly oriented, mark the ground so you can put it back in the same place every time. Try to have the azimuth adjustment close to the centre of its travel.

On a hard surface some paint will do. If the tripod legs have pointed tips, you could even drill holes for them to drop into. On grass, some short stakes driven to below grass level.

Being able to plonk the tripod down in the same place every time saves me 15 minutes in setting up.

sheeny
30-05-2010, 04:46 PM
There's more than one way to skin a cat... I mean align a scope.;)

As already mentioned, use a compass for rough alignment, and then drift align...

or...

use the method in this thread:

http://www.iceinspace.com.au/forum/showthread.php?t=28422&highlight=polar+align

If you are only doing alignment for visual work, this will get you close enough. For guided astrophotography, you definitely need to drift align.

Al.

jjjnettie
30-05-2010, 04:52 PM
On grass, I use plastic Golf ball markers.

graway
30-05-2010, 07:36 PM
Thanks to all for your help
Looking forward to trying this ASAP