Bausch and Lomb Zeiss Protar Series V 141mm F18 EX. W. A. lens (covers 8x10)
Protar V lenses offer a massive 110° angle of coverage (at smaller stops), which makes this 141 mm lens capable of covering 400 mm. This means that it covers 8X10 with room for movements.
This lens is tiny - it is about 1.5" in diameter, and about 1" tall. It weighs 3.2 oz.
Ron Wisner had this to say about this lens:
"This has long been one of my favorite lenses for 8x10. Many of my portfolio images have been taken with one of these lenses. I do not like to mount these in shutters, but rather, use the original barrel and a lens cap. You get the most coverage this way, and they are tiny to carry, weighing only a few ounces."