Jump to content


Video train not aligned?

  • Please log in to reply
3 replies to this topic

#1 James Cunningham

James Cunningham


  • *****
  • Posts: 3308
  • Joined: 07 Aug 2010
  • Loc: Maryland

Posted 07 May 2013 - 06:44 AM

I have a Mallincam that I also use with a filter wheel. I had to cut down the filter wheel so that the camera did not hit the base of my mount. I am afraid that I did not make a straight cut and the camera is slightly mis-aligned with the scope. What kind of problems can this cause? Any effect on alignments? What about the images? Thanks.

#2 rmollise



  • *****
  • Posts: 16047
  • Joined: 06 Jul 2007

Posted 07 May 2013 - 07:35 AM

Depends on how bad it is. It will be no mystery if you have this problem: stars on one side of the frame will be out of focus.

#3 GlennLeDrew


    Voyager 1

  • *****
  • Posts: 11136
  • Joined: 17 Jun 2008
  • Loc: Ottawa, Ontario, Canada

Posted 07 May 2013 - 12:26 PM

As Rod notes, the primary problem is a tilted focal surface, which results in a systematic variation in focus across the frame.

#4 Dragon Man

Dragon Man


  • *****
  • Posts: 2066
  • Joined: 07 Mar 2006
  • Loc: Snake Valley, Australia

Posted 08 May 2013 - 10:40 AM

G'day Jim,
you'll soon know.

I had my MCX a tiny fraction out of square and the stars were out of focus on the left side.
When I focussed the blurry stars, the stars that were in focus were then out of focus :lol:

Mine was caused by the focuser eyepiece locking screw sitting wrong and allowed the cameras nose-piece to sit in the focuser slightly off square.
I fixed this by using a small piece of electrical insulation tape on the opposite side of the lock screw.

But yeah, even a small amount off square and you can see a bit of a difference in focus across the image.

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