Quote Originally Posted by sanking
The blue film base must be anti-halation backing that was not removed in normal processing. Soak the film in a dilute solution of sodium sulfite (1 teaspoonfull per liter of water) for about ten minutes and the blue base should go away.

Stain should not add extra printing time with silver papers unless the film was over-exposed, or developed much to much, or the film is outdated and has a lot of B+F.

According to Foma this film is actually made with a blue polyester base... I used a waterbath beforehand, but will try the sodium sulfite soak and see if there is any anti-halation backing still left in.