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4” MA Galaxy Secondary w/Astrosystems Holder Sold!

Price - $250.00

Ad Number: 130595

Posted: 03 Mar 2018

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I purchased this secondary along with a 22” F/4.16 primary mirror from John Lightholder as a matched set. This is from John’s own personal telescope. John designed his scope to incorporate the 4” minor axis secondary for minimum central obstruction.
Being a wide field, deep sky guy myself, looking at my design showed the 4” was the bare minimum size I could get away with. From past experience though the true measure of whether or not I would be happy with the minimum diagonal size (besides the image) was whether or not I could see the entire image of the primary mirror in the secondary for ease of collimation. As it turns out I couldn’t so opted to upsize to a 4.5” minor axis secondary.
The mirror is from Galaxy Optics, is 1” thick. As shown in the picture it has text written on the back though the first three alpha characters are hard to read.
The mirror was recoated in 2013 and placed in storage as was the primary.
The secondary holder is from Astrosystems. It has a 3/8” stud for mounting to the spider. It also has a built in offset of 7/32”.
Both the mirror and holder were only installed in my scope once to determine if they would work or not and then placed back into storage.
Contact me via PM with any questions you have.

Price includes shipping conus.


  • Condition New
  • Location NE Ohio

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