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Old 13-01-2009, 06:28 PM
AndrewJ
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AndrewJ is offline
 
Join Date: Mar 2006
Location: Melbourne
Posts: 1,905
Quote:
“ the TDM can reduce this down to +/-1 arcsec”.
Another very dubious claim.
With my Mech Engineer hat on,
if the encoder used is of good enough accuracy, and the motor feedback loop quick enough, this claim is probably valid,
but getting a perfect RA Axle "tracking rate" doesnt help synchronise the "entire mount" to the sky, which is where all the argument comes in.
An absolute encoder on the RA shaft will certainly "proactively" remove the bulk of PE and backlash from the drivetrain, but some form of guiding ( albeit now much smoother ) will still be required to give round stars
And its round stars that count.

Andrew
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