Freaking yard sales

Not so much a darndest thing, and the metalworking connection is I need to make a foot adapter for my dovetail clamp. But last weekend, scored a Perkin Elmer 800mm catadioptric lens for $125. T-mount, but I had an adapter to mount it on my DSLR. Having a smaller sensor gives me a 1.5 crop factor, so the lens equals a 1200mm lens on a 35mm camera. Set it up on a tripod and pointed out at the furthest trees I could see (which Google Maps shows to be about .12 miles away) and I can count the pine needles at the top! These were designed for the military, not sure how many were sold commercially by Perkin Elmer, but they were also sold under the Vivitar brand. In 1975 dollars it would cost around $2400 today. Been looking for a telephoto, can't say I don't have enough reach anymore...

Jon

Those lenses were legendary in the optical design community, as was its designer, the late Juan Rayces. If it is really a Perkin-Elmer brand and not a vivitar, it is probably worth quite a bit as a collectors item to the right person. Perkin Elmer did not usually sell consumer optics and they got out of the business very quickly. This design is called a "solid cat" because it is a catadioptric lens where the space between the mirrors is filled by glass. There is a great interview with Juan where he talks (halfway through) about the the design of the lens.

WOW! I saw several variants of the solid-glass design in ATM 3, but did not realize that anyone had actually made them. The optical glass alone was probably several hundred bucks.

-- Best -- Terry

What's that thing weigh?

Pete Keillor

Well, actually the point is it is so short, about 80 mm for an 800 mm f.l., that it does not weigh much at all.

Cool!

By the way, according to Sky & Telescope, there's a satellite coming down in a week or so. This one isn't that big (2.5 tons), but there's a 1.5 ton telescope of some high heat glass likely to make it through the atmosphere. Likely to be more interesting if over land than the recent very large satellites of less dense stuff.

Pete Keillor

Wow! Sounds like it'd work better with an older metal frame film camera than the current generation of super light plastic wonders. I guess you treat the camera back as a non load bearing accessory.

Pete Keillor

Short does not translate into light in this case. The main optic is one solid chunk of glass.

It's 5" long, 4" dia, and weighs 3.7lbs. That's enough weight to damage the mount on the camera body if handled carelessly.

Jon

It's a genuine Perkin Elmer lens. Included was a two page instruction sheet that starts off by noting it's a cosmetically imperfect lens, though no imperfections will affect image quality. It also strongly cautions due to weight, that when attached to the camera, always support the lens, never hold just the camera alone.

A separate sheet of paper lists the Casey Ave Perin Elmer address, with a short list of three names, and serial numbers. So I know who originally got this lens from them. And it came in a cool military grade case for some sort of night vision device's battery. Need to cut some foam for a better fit, but it's sure as hell secure in that case!

Jon

Thank you for the link, that was interesting reading. This lens is probably even more a rarity than I first thought!

Jon

Yeah. My brother cautioned me that the Sony Alpha lens mount is rated to hold the camera's weight. Anything heavier calls for a foot mount on the lens so the mount is not overstressed.

I just found two copies of this lens on eBay with a BIN of $1100! Not my best yard sale score ever, but pretty darn close...

Jon

Yes, but still lighter and much shorter than a conventional refractive 800mm lens, but perhaps not as light as a modern catadioptric with aspheric elements. Aspherics have become much cheaper in recent years.

The 5" length includes the shade in front, right?

Yes. But the paperwork that came with it cautions users to support the lens by hand and not rely on the camera mount. That was back in the 70's before cameras incorporated a lot of plastic.

Jon

This would be one of the "keyhole" class units from the NRO? Or, not one of the US instruments?

Jon

Sheesh, people. Get Borat to climb up the tower there and check the wiring and the pointing of the satellite. You're a bit late on getting your news.

German, "Rosat". Here's a link:

Apparently just came down last night.