TXP (sheet and 120) is EI:320. TX (35mm) is EI:250. Develop both of these films in PMK for 14 minutes @68F. Have you tried HP-5+?? This is a much better film. Ruler flat HD curve. True speed of 400. Develop HP-5+ for 14 1/2 minutes @ 68F.(posted 8770 days ago)