« on: December 19, 2013, 02:52:51 AM »
"If you know of any other extremely fast lenses, please share it with us.
Thank you for this interesting link. The champion is the Zeiss 40mm F0.33, but this one is not useable for photograhpy.
The late Lex Werkheim told us the fastest lens possible would theoretically be a F0.5, but he did not tell us how this was calculated.
Anyway, I think 0.85 is already too fast to be useable in real life photography, except possibly aerial photography (over a flat coutryside) or x-ray photograhy. The only advantage of such speed that I see is that it makes focusing easier in the dark.