'Evening all.
I just saved this lens from ending up "in the skip" during a physics storeroom clearout in the university where I work.
It's an impressive item to say the least!
I measured it as follows:
Front element clear diameter = 85mm
Rear element clear diameter = 59.5mm
Weight = 2.1kg / 4lb 11oz
The construction is beautiful and so solid; for example there is a knurled brass rear ring which turns smoothly to lift out the rear cell. The barrel is mostly smooth chrome (89 mm diameter) and the front is black-painted brass, with several identifying imprints in white on the retaining ring and the outer edge. These include the British and US patent numbers, which led me to a French webpage where the design is recreated from the patent (unfortunately I cannot find the page again, but I remember it was a 7 element design, double gauss-ish).
The optics are coated with several different reflection colours (various shades of pink and yellow/amber), so possibly multicoated. They are surprisingly clean, but not perfectly so. There is a maroon coloured rear lens cap, apparently made of cardboard with a leather-effect covering.
I held it up to some light sources and found that it projects a large sharp image, around 65mm behind the rear of the unit. It completely illuminates the 6x9 cm focusing screen reflex attachment of my Mamiya Universal, without any perceptible falloff. I suspect that it covers at least 6x12 cm if not 4x5 inch. This is exciting stuff! Could be the ultimate barrel lens!
I have an Ilex #5 shutter with an iris diameter of 63mm; not far off the rear element diameter of 69mm; might be worth an adaptation. Or there's always the Speed Graphic route, but I don't have one.
What really surprised me was when I held a telescope eyepiece behind it; I was expecting a soft chromatic image but instead I found that it was really well corrected for aberrations.
Any thoughts? Anyone ever see this lens before? Any idea of its worth?
Ray
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