Jump to content


Focuser "Lumpiness" got me worried..

  • Please log in to reply
1 reply to this topic

#1 shiner


    Vostok 1

  • -----
  • Posts: 172
  • Joined: 04 Nov 2011
  • Loc: England

Posted 07 December 2012 - 03:31 PM

Hi, I've had a Featherlight focuser on my CPC1100 for eight months now and all gone well.
One of these:

Last night I noticed whilst really racking the focuser all the way in (was imaging Jupiter on Webcam) a sort of "lumpiness" or "jumpiness" in the feel of the focuser whilst focusing. The scope still focused but felt wrong somehow. Got me a bit worried. Don't think it is the focuser itself maybe something gone wrong with the mirror cell? It was cold I hasten to add -3C (not sure what that is in F).
Any thoughts folks please?

#2 Digital Don

Digital Don


  • *****
  • Posts: 2172
  • Joined: 20 Jan 2004
  • Loc: Manteno, IL

Posted 07 December 2012 - 06:10 PM

Hi Shiner,

It's possible that the lubricatant on the baffle tube is the culprit. -3° C isn't really THAT cold (around 27° F) but it could have an effect on viscosity.

You might try running the focuser lock-to-lock a few times to 'redistribute' the lubricant.

Hopefully, it's something simple like that!

Don :usa:

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics