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Salvador:
The 10mm went up with NASA to map the stars, minus distortion, for measurement and calculation purposes. Zero practical distortion. Said to cost approx. 5 to 8 thousand then. Front element heavier than steel, costlier than gold of same weight.
Aware of 10mm, 16, 25, 35, 50, 70, 100 lengths, and two zooms; 18-90, 15-150. Covers 1". I have all these; have heard of a 40.
Came out in at least two issues; original fat barrel, heavy solid brass/steel, and later, smaller, thinner aluminum housing'ed version.
Earliest versions, about 1978? New still available from Germany and environs.
Originally produced for East German social observation cameras requiring highest quality image. Current Zeiss and Leitz primes applying same materials, etc..
Google Docter Optics, download Tevidon brochure. New company still producing part of the line. Hyper quality, resolution, etc..