Hello fellow members, just thought I'd show how I use Gels for countering film fade to some prints, better than just sticking
it in front of the lens, Plumbing fittings can be employed, the plastic sink/ bathroom waste fittings, inch and three quarters
fit the bill. As you can see from pics, the fittings have a flange, cut behind this, and you have a "retaining ring", a gel can be
placed and held in situ with a rubber retaining ring. Simple, bit like me, but these mountings should give you good service,
indeed I have a "selection box" of various gels to counter fade.