Quote Originally Posted by Stephen Benskin View Post
Another important point of theory generally missing in most methodologies. Film speed is about the shadow gradient and not a point of density. That's why the ISO standard has the contrast parameters. How many methods incorporate this concept?
Perhaps I'm accidentally inventing the ISO standard for myself, or at least confirming it, albeit probably with the safety factor.

Film speed as a target net density versus a reference point is an interesting issue when it comes to flare as well. I'm always told flare increases film speed. Well, in a way yes, but if the toe is flattened by flare, I haven't gained anything. In fact I've effectively lost "speed" because local contrast has been flattened in the shadows.