Quote Originally Posted by ac12 View Post
The comment about the lens hood actually has some merit, but for a totally different reason.
I use a lens hood on my EL-Nikkor 50. It has kept my fingers off the front element when I reached up to turn the aperture ring...but did not grab the lens quite right.
I hear you! Just today we cleaned the bottom glass of 29 enlarger lenses, and dusted off the top glass (19 enlargers, 5 with 3-lens turrets). Not all were dirty, though, so we did skip a few bottoms, but got all the tops. We did this three weeks ago, also.

Last week was checking the alignment on all of them (most were still good), the week before that was checking and cleaning condensers.