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Home > Classifieds > Astromart Classifieds > Telescope - Reflectors > Classified #286265

For Sale: 12.5" Portaball f/4.8 Sale Pending [SOLD]

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12.5” f4.8 Aluminum Sphere Portaball with a superb Zambuto mirror

Some information on the optics:
My wife fell in love with this scope at a star party in 2001 and we bought it. The mirror coatings had some imperfections from poor cleaning and we asked Carl Zambuto if he would check and refigure if needed. The re-figured mirror he created has an astonishing figure with a Strehl ratio of .991 and a Wavefront RMS of 1/68th wave. The 2.6” secondary is also nearly perfect, both mirror having center dots.

The overall condition of this scope is excellent. But of greatest importance, this Portaball has outperformed every 12.5” telescope any of us here in Flagstaff have ever looked through, period, and there are some professionals here in Flagstaff that know their business.

We chose not to add any electrics to this scope. Cooling is apparently not an issue, judging by the 20 people usually standing in line to view the planets through this scope. There is something different about a Portaball. It's not a Dobsonian and it's not a Newtonian. We have had many scopes, including models in our observatories, and the relationship one has with a Portaball is just a new experience different than with any other scope. It’s the most convenient and “happy” scope we’ve ever used. It becomes a part of you when observing and is so comfortable to use, you feel nearly joined to it. It just wouldn’t be the same with electrics all over it. Yes, a drive at 350 or 400 magnification would be nice, and a platform might be a worthy addition, but the experience will be different then.

In the photo note:
8x50 University right angle finder with helical focuser (Required rebalancing the sphere weights).

Celestron red dot pointer

NGF focuser

Light shield

The papers attached to the scope are a table of magnifications, and filter data for looking at the planets.

Not visible in the photo are the following:
Light shroud

Space age silver scope cover

2 mirror covers, a heavier “storage” one and a very light one for star parties

Pole container

The Portaball will shipped in the carton that we use to take it to star-parties, a U-Haul 24”x24”x24” with 1” of foam all around the inside, but I’ll double box it for the shipment to keep it safe. We have all the manuals and letters from Peter Smitka, and some articles on the scope.

Lastly, two things. First, why are we selling it? Those who have already bought some of our things know my wife has macular degeneration. She cannot use this scope anymore and there are lots of others things we will enjoy doing together. Second, if you are considering a better scope than you are currently using, do one thing for sure, buy the very best mirror you can afford, then worry about the accessories later.


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