I was recently doing some step-wedge testing and noticed
that anything higher than grade 3.5 looked prettmy much the
same. Here are the details:

Zone VI cold light head (Beseler 45) with Aristo V54 bulb, less
than 2 hours total usage I guess

Zone VI intensity controller

Kodal Polymax filters (relatively new, high contrast barely used)

Luminos Flexicon VC (= Kentmere Fineprint VC, I think), both in
fiber and RC, also Forte Polymax fiber

Silverprint Tektol neutral and Tektol standard developers

The Aristo bulb is supposedly designed to work "better" with VC
papers.

It occurs to me just now (that I don't see any available darkroom
time in the next couple of weeks, and being Sunday I can't ask
Aristo) that I normally use my Zone VI controller with the intensity
set at "F" to give me a little longer exposure at f/8. I can achieve
stabilisation typically up to K or L once the bulb is warmed up.

Here's my question - has anyone ever done experiments to assess
contrast grades vs intensity with the Zone VI controller? If so, this
could save me a bit of time and paper; if not, I'll do it myself and
post the results, though it could be a while...

TIA.

Steve