Since I acquired my Jobo|LPL C7700 Pro I have been using the colour filters built into the head to control contrast with VC papers but I have the feeling that I'm not getting as much contrast as I could be out of my negatives. As a point of reference I was looking through my copy of Lee Frost's 'Simple art of Black and White Photography' where he has small pics of the same neg printed at grades from 0 to 5. With my current setup, even with the magenta set to full I don't think I can even get a proper grade 3 out of my negs. I am assuming that as the built in filters are old, quite well used and they may have faded, so I was toying with the idea of buying a set of MG filters to use instead. The question I have is that there is a yellow leaver on the side of the enlarger's head that moves the diffuser up so you can get the neg carrier out easily, it is then lowered down when you put the neg carrier back to apply a little pressure to keep the negs flat, however, I was wondering whether I could buy a set of MG filters that normally go in the filter drawer but put them on top of the neg carrier instead. Can anyone see any problems with this? Could it damage the filters etc? Or should I just go for the below the lens filter set instead?