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20" f/4 Mirror plus secondary Sold!

Price - $4,200.00

Ad Number: 116706

Posted: 29 Sep 2017

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Hello All,

As you know, Florida was hit with Irma. We fared OK here in Key Largo. The mirror (and all my astro stuff) came
with me when we evacuated so the mirror was cool and dry at all times.

This is my first post on CN, so thanks for looking and your consideration.

Up for sale is a Terry Ostahowski 20 inch F/4 2 inch thick Pyrex primary mirror.

I converted my 20 inch f/5 dob to f/4 and had Terry do the re-figure and coatings in Nov 2016. It was a Galaxy mirror I had acquired years back second hand. Terri had to check the anneal and whatnot before he proceeded so it has met his standards to do the re-work. It was basically a blank for him to work with since the original figure and coatings was irrelevant.

Since receiving the mirror, I changed direction to AP and the mirror has never seen first light. It went straight from his shipping box to my custom case, which is included. I still had some unfinished work on the dob to convert it to f/4 so the dob was not ever ready to receive the mirror.

Primary has a center spot put on by Terry.

I can't comment on the mirror's performance but looking at the specs, I would assume it is a great performer.

Also included is a matching 3.5 inch secondary he sold me when he did the re-figure. It has not seen first light either but I did adhere it to a secondary holder and it has some staining on the back surface from the silicon, but the front surface has never been lifted off the tissue covering the front surface that it came with.

I am keeping the dob since I built it myself, put a lot of craftsmanship in it and just can't let it go (you can see it in one of the pics). I may get back into visual one day and all I would need is the mirror set.

I am asking $4,200 OBO plus the PP fee if paid via PP.

I would really prefer not to have to ship it but if the buyer wants to have it shipped, I can drop it off at the UPS store here in Key Largo and the buyer can co-ordinate shipping and payment with them. I deal with them all the time and they are good people. It is best to have them package it so it can be fully insured. Or I can work with the seller if they prefer other arrangements.

I will protect the front surface of the mirror with fresh surgical gauze so the mirror surface does not contact the case foam in case the box gets turned over. Or the buyer can give me any instructions as to how they want the surface protected from the case foam.

Buyer is responsible for the shipping charge and the PP fees.

Hate to let her go, but one has only so much time and money to pursue our passion.


  • Condition New
  • Location Key Largo Florida

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