Quote Originally Posted by df cardwell View Post

Awesome. I'm grateful for folks who see more clearly than I,
and write more coherently !

(Many of whom see to be posted ahead of me !)

Here is a visual aid borrowed from York Univ.

And below, here is the late lamented APX 100 data.
Thanks for the color graph. There is also one in the UV filter link I supplied, although he has the colors reversed from convention.

Wow, that APX is quite the roller coaster, even more than Kodak's general curve.