With the re-release of Tmax 3200 and several thread already started... I am interested to understand how these films are different, any Ilford or Kodak reps comments most welcome! Both these films have an ISO of 1000 or 1200, depending on the developer, so they are obviously more sensitive, a common comment is they have lower contrast at these ISO speeds than what they might otherwise have, but how? A film exposed and developed to the ISO standard will have identical density at an exposure Log(1.3) (about 4 and bit stops) greater than the exposure that results in a density of Log(0.1). The two points while arbitrarily chosen are close to a middle tone and deep shadows respectively. So the contrast ratio between these two points should be same for any film exposed and developed to the ISO standard, indeed I believe the correct value is 0.62. So how are the films different? The ISO test only defines two points, one in/close to the toe and one that would be a mid tone that the films contrast must pass through. That leaves the toe, the path between the two points and all of the density from the mid tones and up, that could be varied, but how? Answers on a postcard.