[time-nuts] Sidereal time
magnus at rubidium.dyndns.org
Sat Jan 16 03:23:56 UTC 2010
Bruce Griffiths wrote:
> Hej Magnus
> No one bothers with such gear ratios for a modern telescope as its
> cheaper to use a computer than have a set of custom gears made.
> In any case, direct drive of the axes is sometimes used - no gears:
> Calculating the time is just the beginning if you want to point to
> Saturn for which the RA and DEC vary over time and the simple model
> isn't very accurate:
I was meaning mathematical gears, not mechanical gears.
The simplified approach was just to present an alternative for those in
need of a little less precission as their scopes and associated pointing
needs is a little less than the large scopes. Just as an idea. The main
idea was that the open-loop calculations could be simplified if a
calibration would create a closed-loop for the offset part and remaining
open-loop errors would be relative negligable for the application.
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