Aligning the Polar

[DemonicOmelette]

Now, possibly a silly question...

I have a south-west facing flat, and am setting up my scope on my balcony. Is it possible to Polar Align my EQ mount using something other than Polaris? Is there a calculation I can use to use Venus, for instance? Venus is at 255' at the moment, and I can get my Alt using my geographic coordinates... So what's the maths to set up my Az?

-eli

[TheThing]

Quick method would be to use a compass and align it to north that way. Not exact, but if you're not taking photos it wont matter.

[DemonicOmelette]

I would try that, except for some unexplained reason, my compass doesn't point north. Bit pointless, that.

[Merlin66]

If you use the drift alignment method, its not necessary to see the pole. Once you've achieved your alignment just mark the floor for the tripod and next time place the feet in the same position; you'll be pretty close.

Here's an extract from JMI's webpage:

First, choose your star near where the celestial equator (i.e. at or about 0º in declination) and the meridian meet. Center the star in the field of your telescope and monitor the drift in declination.

• If the star drifts south, the polar axis is too far east.
  
• If the star drifts north, the polar axis is too far west.
  

Using the telescope's azimuth adjustment knobs, make the appropriate adjustments to the polar axis to eliminate any drift. Move to the star near the eastern horizon. The star should be 20 degrees above the horizon and close to the celestial equator.

• If the star drifts south, the polar axis is too low.
  
• If the star drifts north, the polar axis is too high.
  

This time, make the appropriate adjustments to the polar axis in altitude to eliminate any drift. Repeat the process again to improve the accuracy, checking both axes for minimal drift. Once the drift has been eliminated, the telescope is very accurately aligned