NCP algorithm

[Gazabone]

More out of curiosity than anything else but wondered if anyone knows the algorithm for positioning polaris in a polar finder scope along the lines of Jason Dale's rather nifty bit of software to position it akin to a clock face. I know finderscopes come with etched constellations but I think using a clock face approach is more accurate.

Whilst I have Jason's software on my iPad, I don't particularly want to take it out on observing sessions. I have a blackberry phone and the software doesn't exist for it.

I've searched the web but couldn't find an equation for it.

Cheers

[Astrobits]

Not an equation but this is one method:

http://www.arksky.org/Kochab.htm

Nigel

[Gazabone]

Thanks Nigel,

Think I might make a planisphere based on this similar to the no longer available Celestron Polar plate.

Cheers

Gareth

[thohem]

What mount you got? You can use the pitch circles for a fast and more accurate polaris position.

Set the RA circle to 0 when polaris has highest position, look at handset for polaris clock position and set RA axis with the pitch circle to that exact location then use screws to get it into the circle. No need for an app nor some calculations. Just needs 5min setup and your far better aligned than with those constellations