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William Optics huge 2-inch 90 degree Erecting Prism Diagonal 2018

Auction No.:
Current Bid:
High Bidder:
William Gaudet
Bid History:
15 Bids [View History]
Spokane Vly, WA - United States
06/10/2024 07:46PM
06/20/2024 07:46PM
Time Left:
Buyer pays shipping
PayPal, Personal or Cashier's Check, Money Orders
Ah, yet another product that needs no introduction...

This is a 2018 William Optics 2-inch 90-degree Erecting Prism Diagonal. It is complete with both setscrews for the 2-inch and 1.25-inch barrels, a top dust plug for the 1.25-inch adapter and a bottom dust cap for the big barrel.

This is not complete to code, however. The 1.25-inch adapter, though an absolute perfect fit, is not original to the diagonal because it has no inner compression ring nor does it have an inner recessed channel to fit an inner compression ring system. To my knowledge, all WO diagonals of this era-onward did have compression ring assemblies in their diagonal systems.
So, the diagonal itself is all original. The 1.25-inch adapter and its setscrew are not.

Big, heavy (1.3 pounds) 90 degree BAK-4 glass prism that will make all images upright and correct. The STOP sign will be seen as STOP. Oh, and there are female threads in the focuser insert barrel of the diagonal that accept your 2-inch eyepiece filters; how cool is that?!

Want one of these new today from WO? Start wishing. They ended production back in Jan/Feb of 2022 and it doesn't look like it will be returning.

Physical condition of the diagonal is perfect; no chips, deep gashes, dents, missing hardware, replaced hardware, or modifications are present. The setscrew and all the hardware holding the diagonal together is perfect with no rust or stripped threads. Cosmetics on the diagonal are excellent if you can see past the sunlight fading. The milled, anodized aluminum triangle body should be a very dark graphite-gray (almost black) in color. With this unit, it is now pencil lead-gray. Still quite pretty, but not to-code anymore.
The eyepiece insert barrel is in solid excellent cosmetics with a deep, black gloss look, yet not without a few tiny contact marks here and there. The focuser insert barrel is in great condition with a silver-looking score that runs all the way around the barrel. Nothing bad, just from setscrew contact over the years. It won't be visible at all when attached to your refractor or cassegrain.
Female threads in the insert barrel are perfect.

The bushed aluminum side and underside panel accents are in very excellent condition on the sides and great condition underneath. ALL the painted characters are perfect and vibrant with no breakage. The original quality label is perfect. 

The prism exhibits perfect collimation and is not loose or jiggling. Physical condition of the prism is perfect with NO cracks or chips or scores to any part. What you see in the photos of the prism that look like chips on the facets are actually the contact points of the tiny, internal setscrews that hold allignment.
Coatings are in solid excellent condition with very few, hard to see micro pits in sporadic areas and some light internal dust. Absolutely no need to clean for a very long time. If this was freshly cleaned right now, I would state it to be in very excellent condition optically. But like I said earlier, no need to clean. Your views will be marvelous in this prism!
Time Placed User Bid Amount
06/20/2024 02:26AM William Gaudet $90.26
06/19/2024 11:58PM Louis Fico $87.50
06/18/2024 05:59AM John Rogers $76.27 [ Auto Bid ]
06/18/2024 05:59AM William Gaudet $73.77
06/17/2024 02:31PM John Rogers $71.27
06/17/2024 12:20AM Steven Hilliard $64.50
06/15/2024 10:38PM John Rogers $30.00 [ Auto Bid ]
06/15/2024 10:38PM William Gaudet $27.50
06/15/2024 03:01AM John Rogers $21.50
06/13/2024 04:17PM John Wetmore $12.88 [ Auto Bid ]
06/13/2024 04:17PM Louis Fico $11.38
06/13/2024 08:29AM John Wetmore $6.50 [ Auto Bid ]
06/13/2024 08:29AM William Gaudet $5.00
06/11/2024 07:44PM John Wetmore $2.00
06/11/2024 04:45PM Louis Fico $1.00