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I believe that the reticle in my polar finder may be based on the precessional position of the earth's axis in AD 2000. Certainly there is no date printed on it  and there were no instructions. Does anyone know whether  reticles are available  which are more up to date and if so where I can get one which will fit my  Celestron polar finder

Thank you for your replies.

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References elsewhere on the internet and one in particular which mentions a piece of polar finding software which has been tweaked to  make allowance for the date changes.Of course I could buy the software but there may be another way.

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yes the info is 14 years old on polar north and as it drifts it may be off
as you say some software like Alignmaster have compensated for this

but as far as I know all polar scopes are based on the same info from 2000

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Hello Persecundo,

May I welcome you to SGL, and I hope you enjoy your stay.

A complete axial precession cycle takes 26,000 years, so I wouldn't worry too much.

This is the first time I've seen this mentioned on the forum, but that isn't to say it hasn't been.

Star charts and atlases are modified every epoch, which is a period of 50 years, whereby any small changes in the Right ascension and Declination of stars and other relatively fixed objects, are changed to reflect their new positions.

Apart from Barnard's Star, which has a fairly large shift in position I don't of any other rapid moving star that need large alterations to their coordinates, but there may well be others.

Best Wishes.

Ron.

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Thanks for your replies gentlemen. You have confirmed what I suspected. Clearly this is of no importance for observing but if and when I attempt to take photographs I may give more consideration to  the  matter, especially as the telescope I have purchased has a large focal ratio.

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Here is the data 2014 to 2020:

With your reticule line aligned Cassiopeia to Mizar, Polaris should be placed at the distance from centre as follows (on the line from the centre to Mizar):

2014: 41'

2016: 40'

2018: 40'

2020: 39'

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