Quote Originally Posted by Arcturus View Post
Thanks for the replies! It really nails the contrast w/o a filter, but I think I may start using them every time now seeing what everyone is saying. If I ever change enlarger heads I could get myself into trouble not really knowing what grade I'm printing to. I was just going on the "if it isn't broken, don't fix it", but I think I'll save myself some trouble in the future by starting to use the filters now.
You won't save yourself trouble. The grade numbers on the filters are arbitrary; the actual contrast you get in your prints is affected by a number of other factors as well, including light source, paper and developer. If you change your enlarger head you could well end up with different behavior, just as if you change paper or developer. It's possible to be more precise about this by making careful sensitometric measurements - get a copy of Phil Davis's "Beyond the Zone System" if you're interested in learning more. But you don't need to if everything is working fine for you.

FWIW, I use an LPL 4500II with color head. I dial in yellow or magenta filtration as needed by the particular negative + paper combination I'm using. If the negative doesn't need any filtration, then I print without any filtration.