This Rank-Taylor IRTAL 200mm f/1.0 lens is currently listed on eBay for $389k:
"This item is a very large and very fast germanium objective lens for a thermal imager or thermal imaging camera. The focal length is 200mm, and the maximum aperture is F1.0 The front element is 20cm in diameter. Made by Rank-Taylor in the UK.
There is an aperture adjustment ring, with settings from F1 through to F5.6. There is also a focus ring with settings from 7 feet to infinity. The body has a threaded rear mounting on a removable adaptor plate. At the front, a removable hood and cap.
A wooden shipping/storage crate with foam lining is included. The lens condition is very good, looks absolutely perfect, may have never been used. Please note, this is a VERY large lens, it weighs 18kg. Tomato soup not included."
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