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inline_online
06-06-2012, 12:59 AM
Hi,

I am curious as to what astro-imagers do when they do not have access to a permanent set-up and need to set-up their gear quickly on grass.

This has not been a problem in the past as I could do a quick and dirty polar align by sight for visual astronomy and that worked fine. However, i've started imaging stellar spectra and need more accurate polar alignment.

If I had a paved backyard, i'd spend a bit of time doing a good drift-align them marking the positions of the tripod legs on the ground. I have grass though (which is better thermally:)).
Are there any markers that people can use to indicate where the tripod legs should go each time they set up? I can't have things sticking out of the ground as my two boys play on the grass every day.

Any advice would be great as i'm not keen on drift aligning each time I set up.

Cheers,
Dan

Octane
06-06-2012, 01:01 AM
http://www.telegizmos.com/365%20Cover%20Page.htm

One of those and leave your gear outside all the time. Win.

H

peter_4059
06-06-2012, 05:15 AM
Dan,

I've got three half bricks sunk into the grass where the tripod legs go. These sit flush with or just below the grass so don't interfere with kids games or the lawnmower!

After polar aligning, I marked where the points of the tripod legs were located on the bricks then used a masonary bit to sink a dimple in each brick (for the EQ6). Then as long as you leave the mount attached to the tripod you just need to place the tripod legs back in the dimples and you're good to go.

For the Losmandy tripod I marked the positions on the bricks with a permanent marker as it doesn't have the pointed feet.

Peter

skysurfer
06-06-2012, 05:55 AM
Pile them into the ground so far that you just can see them and don't hurt playing kids (and also not being hit by a lawnmower).
Make it from e.g. PVC tubing and make a cap on it of a bright easily detectable color (e.g. red).
Of course you should not change the latitude and azimuth setting on your EQ mount.

inline_online
08-06-2012, 10:07 PM
Thanks for your suggestions.
I'll give the bricks a go I think. It sounds like a winning idea and can be my project for this weekend.

Cheers,
Dan