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Captured by
Terry Wood

Jupiter (clearer) Nov 5th 2023 w/Mewlon 180c

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Fast 84mm Doublet (2 of 2)

Auction No.:
12838
Current Bid:
$16.05
High Bidder:
Mark Baribault
Bid History:
7 Bids [View History]
Location:
Scotia, NY - United States
Started:
11/08/2019 03:42AM
Ends:
11/17/2019 07:42PM
Shipping:
Buyer pays shipping
Payment:
PayPal, Personal or Cashier's Check, Money Orders
Hits:
119
This is the second of two. It is an ~84mm diameter doublet, 14mm thick at the edge, with a focal length of 9-inches (~228mm), so about f/3 at an aperture of 76mm. 

Certainly not intended at a telescope objective - too fast for a good achromat at the aperture and not kind to eyepieces at f/3. But it might be fun to play with, perhaps as a finder objective, or maybe some ATM has some other use for a fast doublet. I was tempted to hold onto one of them just because it's interesting. 

It is coated on the front, probably MgF. The back is uncoated. The workmanship is excellent, the surfaces are free of scratches, and the edging and cementing looks fine. There are a few small chips around the front edge and I've tried to properly photograph them all. 

Let me know if you have questions. 

Clear skies, Alan 
Time Placed User Bid Amount
11/16/2019 04:02PM Mark Baribault $16.05 [ Auto Bid ]
11/16/2019 04:02PM Ed Blankenship $15.55
11/16/2019 03:56PM Mark Baribault $12.05 [ Auto Bid ]
11/16/2019 03:56PM Ed Blankenship $11.55
11/16/2019 03:35PM Mark Baribault $5.55 [ Auto Bid ]
11/16/2019 03:35PM Ed Blankenship $5.05
11/12/2019 12:56PM Mark Baribault $0.05