I just got a brand new Cary 50 spectrophotometer. So I thought I would look at the spectral transmission of a couple of my lenses. The following graph shows the 24-120VR lens vs the Schneider Componon-S 135mm f/5.6 enlarging lens: The Schneider does indeed have a bit more UV transmission (50% at 377 nm) but it is very flat throughout the visible range. By contrast the VR lens has enhanced blue transmission, something that may contribute to the 'snappy' color quality I find with that lens. I hope to get some time soon, and check out all my lenses.