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Old 07-10-2015, 09:54 PM
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Allan_L (Allan)
Member > 10year club

Allan_L is offline
 
Join Date: Mar 2008
Location: Central Coast NSW
Posts: 3,339
a copy from cloudy nights (starman1): Re Paracorr in Sw DOB:

Quote:
Hopefully, your focuser is not the dreaded one with the ring on the drawtube into which fits either a 2" adapter or a 1.25" adapter.
Because if that is the case, the scope will not focus without some modification.
You see, the focuser ring has an inside diameter of 1-15/16", so a long 2" accessory (like a barlow or the Paracorr) will not pass through the ring on the focuser to sit solidly on the 2" adapter--the long accessory will bottom out on the focuser ring and require a couple inches of additional infocus beyond the roughly 3/4" the Paracorr needs anyway.
What you have to do is to remove the ring from the focuser and either machine out or simply sand out the internal diameter to slightly larger than 2" so the Paracorr will slide past the ring to seat fully on top of the 2" adapter. Otherwise, the scope will never come to focus.
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