Jump to content


Photo

Howie Glatter Holographic Attachment?

  • Please log in to reply
4 replies to this topic

#1 cloud_cover

cloud_cover

    Viking 1

  • -----
  • Posts: 563
  • Joined: 17 Aug 2010
  • Loc: Restaurant at the End of the Universe

Posted 29 January 2013 - 01:05 PM

I've finally gotten round to installing the optics into my new scope but the centering of the secondary frustrates me in that I'm not sure its actually centered in my focuser. Now I've got teary eyes from squinting down a sight tube.
Do you folks think the Howie Glatter Holographic Attachment that produces a grid pattern over the secondary is a good idea? I'm thinking of getting the BLUG anyway
Thanks for your thoughts!

#2 Jason D

Jason D

    Fly Me to the Moon

  • *****
  • Posts: 6668
  • Joined: 21 Oct 2006
  • Loc: California

Posted 29 January 2013 - 03:28 PM

Check the information in this thread
http://www.cloudynig...eflectors/Nu...
Jason

#3 stratocaster

stratocaster

    Messenger

  • *****
  • Posts: 426
  • Joined: 27 Oct 2011

Posted 29 January 2013 - 04:51 PM

You may also want to see this. I had the same question on using the holographic attachment.

#4 Mark Peterman

Mark Peterman

    Vostok 1

  • -----
  • Posts: 105
  • Joined: 07 Aug 2012
  • Loc: Texas

Posted 29 January 2013 - 04:54 PM

While I can't answer your question, I have had the same experience.

What I found easiest is when you can center the secondary under the focuser while the primary mirror is out of the scope. It just makes things easier to see and what you see makes more sense. If you don't want to remove the primary, simply hang a white piece of paper behind the secondary so that it blocks the reflection from the primary.

Doing it this way, there is no need for a white piece of paper on the opposite side of the focuser. The dark contrast of the tube and the white reflection of the paper in the secondary mirror makes it clear as night and day to see how centered and round the secondary is.

#5 starman345

starman345

    Wait, I'm Thinking

  • *****
  • Posts: 9250
  • Joined: 06 Jul 2010
  • Loc: New Brunswick, Canada

Posted 29 January 2013 - 08:03 PM

I don't have Howie's holographic attachment so I can't help you there but I"m wondering if you have tried pulling your sight tube as far back in the focuser as possible? I have to set mine that way before I can see the edges of the secondary, once at that point its easy to center it.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics