Polar alignment?

[ncstarhawk]

If you are polar aligned and observing tonight, you have not moved the mount, put the mount in cwd position (all manual, no goto) cover the scope and the mount, why are you not aligned for the next night?

[Elp]

Polaris moves throughout the year as the earth goes around the sun (and also as the solar system travels) as far as I'm aware hence why on polar scopes you have a clock around it to align to via offset, I would also say the physical setup is also prone to variation either mechanically or due to temperature.

Edited October 27, 2022 by Elp

[scotty38]

Polar align one night and then don't physically move it other than slewing? In that case you will still be polar aligned the next night assuming no external forces have moved it like tripod sinking into the ground....

This is no different to a permanent observatory setup where you don't polar align every night either.

[ncstarhawk]

That's what I thought also. The alignment is not much off. I am using the Ipolar cam. 

[StevieDvd]

If you were polar aligned and everything was left in the same position then you are polar aligned.  You are not aligned with polaris, that transits a small circle around the NCP.

Then to repeat the alignment process it would again use polaris as a reference point (and need the date/time/location set correctly) would show you are still polar aligned.

The 'not much off' value is often the base for visual sessions or short guided imaging.