SCP compass location

[Paliadon (Kris)]

G'day guys, I have gone and got myself confused and I need some feedback to get me back on the right track.

I am having difficulty with polar aligning my NEQ6 due to street lights that have been erected in my street that wash out pretty much everything 25° above the Southern horizon.

In order to compensate and get as close as possible to the SCP I am going to use a stringline (compass engaged) line across the top of my pier so I can align my scope perfectly.

Herein line the problem: I have confused myself. Magnetic South is 180°, my magnetic deviation is 11.4°, so I now have a True South of 168.6°?

One, is my maths correct? and Two, am I right in thinking I need to take a compass bearing of 168.6° to ensure I am lined up with the SCP?

Phew.

Anyways, that is my query, I hope I haven't gone and confused the issue.

Cheers

Kris

[Scorpius51 (John)]

Hi Kris

There is a guide in the Projects & Articles area http://www.iceinspace.com.au/63-405-0-0-1-0.html
that will sort you out.

Cheers
John

[Paliadon (Kris)]

Thanks for the quick reply John, the link you suggested looks to be just what the doctor ordered.

Cheers,

Kris

[originaltrilogy (Petr)]

If in doubt use solar noon method.
Is good check to make sure compass line is correct.

[Screwdriverone (Chris)]

Hey Kris

Yep, you have the maths correct and the idea is spot on.

You need to point your scope to 168.6 degrees (which is about 12 degrees EAST of south on a compass).

This SHOULD get you close enough to the SCP, as long as your altitude is set correctly based on the angle the LATITUDE scale is set. Be aware, these are notoriously wrong on Skywatcher GEMs (mine was more than 10 degrees out) so try and set this with a protractor or digital angle gauge to the LATITUDE of your location.

I know you have some bad LP in the direction of the SCP, but try my tutorial here, to narrow down the asterism that is Sigma Octans etc. These should hopefully be visible in the 9 x 50 finder.

Cheers

Chris