one leg pointing north on tripod

[Larkspeed]

How important is it for this to very very accurate?

I realize the mount sitting on top of the tripod has to be pointing properly north and this in not hard to do as I have a flat surface on mine to rest the compass against.

But on the tripod I do not have a handy flat surface, I can use the bracket at the top of the leg (legs are not magnetic) but I cannot be 100% sure this is bang on north.

Will that be close enough or does it have to be exact?

Like I say I can rotate the mount on the top of the tripod to get proper polar alignment anyway.

[IanL]

It only matters if you have a mount with and azimuth adjuster and you reach the maximum travel in the adjuster before you get aligned. Usually lining up the tripod by eye is close enough; if you are setting up in the garden, you may be able to make some marks for the tripod legs once you are aligned. ( just drilled three indentations in the concrete patio and marked them with white paint so I could find them again. You can then drop the tripod on to the marks next time and save a minute or two.

[Larkspeed]

OK thanks for that

I move my scope around to different site so making permanent marks is not possible.

What I was doing was carrying around a long straight edge that I would align on the ground using the compass, this created a perfect east/west line then placing the two back legs against the edge would align the front leg north.

This is a bit of a pain though because my entire scope fits nicely into a large plastic box that I use to transport it encased in foam but the straight edge did not fit and was a pain to carry with the box.

But now I know roughly north is good enough I won't bother with the edge anymore.

[Buffalo Bill]

I just line up the front tripod leg with polaris by eye and use a built in level bubble then use azimuth adjusters to align the head more accurately and get perfectly usable alignment for visual use

[Larkspeed]

I would but my tripod does not have a level built in

I carry a small spirit level in the box

[LukeSkywatcher]

When i used a scope with an EQ mount, i simply lined the polar axis leg up to roughly where i thought north was (i didnt use any compass etc and i could not visually see Polaris). I then got the Moon (or any other bright object) into my FOV and saw how quickly it raced across my FOV. Iy was then just a case of moving the other tripod legs a bit to the left or right until such a time as my target stayed in my FOV the longest. Then i knew i waspretty spot on. I then laid down 3 little marker stones to remind me where the legs should go. Thats fine if you observe from the same location every time, not so good a technique if you move about.

For purely observational astronomy, its not important to be very accurate but for imaging...............you have to be spot on evey time.

If your scope is on an EQ mount the above comment (by myself) makes sense. If your scope is on an Alt-Az mount, then all you need is a flat surface and the star aligh will figure the rest out.

[LukeSkywatcher]

I would but my tripod does not have a level built in

I carry a small spirit level in the box

What scope do you have?

[Larkspeed]

Celestron Astromaster 130EQ

[baggywrinkle]

If you have an iPhone download ScopeTools, has a bubble level meter, compass with both true and magnetic options. In the UK quite important as the magnetic deviation is quite large.

I always use a compass to set my polar alignment. This was more important when I was in Aus' as the SCP star is a dim wee beast.

[Gomtuu]

I seem to remember that if you can't see Polaris, you can get a good approximate north-south marking during the day by setting up a vertical stick/pole/ruler then marking where the shadow is at solar noon. You can then use this later to get a pretty good alignment with your tripod.

Here's a solar noon calculator :

http://www.spot-on-sundials.co.uk/calculator.html

[cfpendock]

I seem to remember that if you can't see Polaris, you can get a good approximate north-south marking during the day by setting up a vertical stick/pole/ruler then marking where the shadow is at solar noon. You can then use this later to get a pretty good alignment with your tripod.

Here's a solar noon calculator :

http://www.spot-on-sundials.co.uk/calculator.html

But don't forget to allow for summer time / winter time.

Interestingly, I set up with my tripod leg south.....

chris

[Tinker1947]

The only reason for having a Tripod leg facing north is it makes it easier to look through the polar scope it could point south and with the handset (NEQ6) software aligning the PA you don't need to be able to see Polarus or use a Polar Scope....

[Gomtuu]

The only reason for having a Tripod leg facing north is it makes it easier to look through the polar scope it could point south and with the handset (NEQ6) software aligning the PA you don't need to be able to see Polarus or use a Polar Scope....

Although I take the point that you can polar align without using a polarscope,I have an NEQ6 and when the polarscope faces north, the "pointing leg" points south anyway, not north.

[Gomtuu]

But don't forget to allow for summer time / winter time.

Indeed.

[IanL]

Although I take the point that you can polar align without using a polarscope,I have an NEQ6 and when the polarscope faces north, the "pointing leg" points south anyway, not north.

Many people reverse the tripod by removing the azimuth adjuster pillar and screwing it in to the other hole provided for the purpose.

[Gomtuu]

Many people reverse the tripod by removing the azimuth adjuster pillar and screwing it in to the other hole provided for the purpose.

Ooh, didn't know you could do that. That's handy!