Quote Originally Posted by David Lyga View Post
For the life of me I cannot understand why Kodak did this in the first place. Didn't they test things thoroughly?

Rjmeyer314's comment makes me wonder why Kodak, and ONLY Kodak allowed this fautly theory to 'develop'. As he says, the ridges prevented as free a flow of solution, as was necessary, and as was entirely possible with spirals we use today.
I've used aprons a lot (particularly with 616 film, but also with 120), and they worked well. You do need an apron that is just the right size for the width of film involved.

They worked well in the Kodak tanks, but not so well in others that didn't have the same dimensions or the same "stub" at the bottom of the tank.

I stopped using them regularly because the Kodak tanks don't permit inversion.