I'm using Fujicolor CrystalArchive paper with Rollei Digibase RA-4 Monokit developer. I use an old russian enlarger at f/16 that has no filters (apparently it's been used for b&w). All of my prints have an orange mask on them, completely monochrome. I tried exposing it longer/shorter, keeping it in the developer longer, still they have some kind of orange fade (only darker or lighter).