Lith film is not pan for one thing. This makes it useless for color masking and a distinct
liability when masking pyro negs due to the stain of the original image. It's not particularly
predicatable batch to batch. Dektol gives a fair amt of residual fog. This approach might
be acceptable for certain personal uses, but it's a pretty bad starting point for any objective learning of masking skills, esp if one wants to ever get to second base. The key
to high quality contrast masking is to have a very low contrast dimensionally stable image
registered with a straight line as far down as possible, and a minimum amt of base and edge fog. Even old time Pan Masking film had a horrible toe to it. It was basically Plus-X
minus the antihalation layer. With FP4 and TMX and certain very dilute tweaks of HC-110
you can be properties much closer to ideal, plus use correction filtration relative to color
response (which in fact is a factor often in even black and white masking).