How does AA creep into this equation? His work has aritstic and historic significance and he put a lot of effort into it, but his enlargements were pretty damn fuzzy compared to what can be done today.
That's why he used matte paper for anything bigger than 20x24. We've got way better film, enlargers,
and lenses than he did - in fact, some of his dkrm gear was badly out of date before his career ended.
No pro lab would have used such things. I don't think there ever was a 600 Apo El. The regular Apo is
common, though I doubt he owned the latest version. He wanted distance between the horizontal enlgr
and himself, so he could sneak around and dodge/burn close to the vertical panel where the paper was.