As the others say TMY is more sensitive to development variations than Delta 400, Tri-X and HP-5. TMY has smoother (not really finer) grain than Delta 400. Delta 400 has more of a shoulder than TMY, so highlights don't go real dense so easily. TMY is less finicky when developed in Xtol. In fact, I hated Tmax until I tried it in Xtol. Developed in Microphen I get 1/2-1 stop more speed with Delta 400 and TMY and very slight grain increase.(posted 9503 days ago)