I ran acros a box of old expired Kodak Porta Black & White paper, but for $6 bucks I decided to give it a try. no matter what I tried , I kept getting a magenta cast while printing a contact sheet. Today I decided to go on and try to print the first picture regardless. I printed a strip of 2 sec steps (2-4-6-8sec) and to my suprise, very good black and white tones. I was happy and found my perfect exposure at F16 for 7 sec. What do I get a horrible and quite heavy magenta cast. So I thought maybe cause I am reusing the developer. So I tried a fresh batch of developer. Horrible magenta cast. I tried changing the exposure to F11-3.5sec just in case (shouldnt matter but I had to try), I get horrible magenta cast. what gives ? what is causing this magenta cast. I originally thought maybe 'cause the paper was expired, but that one test strip came out perfect... I duplicated exact temperature, process time and Filter pack I had used during the test trip. nothing,: I get magenta cast. I don't get it ? thanks for any ideas.