Quote Originally Posted by Simonh82 View Post
As the enlarger is new to me, I checked all the lenses (it came with four) and put this one on for the printing session. It definitely stops down correctly and you can see the change in illumination as it does so.

I am also sure that I didn't leave it on f4. This Schneider lens has a useful leaver which allows you to easily flick between wide open and your chosen f-stop for focusing and after leaving it wide open at least once during my training course, I definitely checked that it was set back to the correct f-stop.
I use the same lens and was going to query if you were stopping it down with the lever... but you seem to be on top of that... and you have verified the aperture blades are moving (although I'd suggest you take the lens out and visually look. Once stopped down to f22 the 'hole' should be pretty small. Maybe it's not actually stopping down correctly. Once all that checks out ok, check that globe!

Just doing some mental arthmaatic... my enlarger requires 10-12sec @ f8 for a 8x10 from MF with minimal filtration, which at f4 would equate to 2-3secs... re-check that lens, or try one of the others?