Before I even get started, I know that the best way to find the answer I might be looking for is to just try things out and see. But I'm curious about what folks who have already tried have found.
I own a 19-inch Apo Artar. I got it as a barrel lens. I just got an Ilex #4 shutter in the mail. The shutter works very nicely, though the Artar lens cells do not screw directly into it. I did not expect they would, though wouldn't that have been nice? Still, the way they don't fit is the best way: the cells are smaller than the adapters that are currently in the shutter (the adapters were for mounting the cells of a 9-1/2 inch Conley Series VI lens; anyone want them?). This means that I can simply use something -- layers of tape to experiment; thin strips of metal for something more permanent -- to center the cells in the adapters; and I can easily tap holes for set screws into the adapters to grip the cells. It will be easy, and I could do it with just my drill press. Or, eventually, once I practice, I can make better adapters for the adapters on the mini mill I recently bought (making entirely new, threaded adapters will not be possible with my skills or this machine).
But I'm writing this primarily because the cells don't fit in another way: the barrel the lens came in is 1.55mm thicker/taller than the shutter with its adapters. That will also be an easy fix, with a simple washer I could make or maybe just buy. My question is: how accurate do I need to be? In fact, do I even want to be? I've read that process lenses were sometimes optimized for infinity use by changing the distance between the cells. But I've read two contradictory statements: some commenters have written that, in order to make them optimized for further distances, rings were used to place the cells farther apart, but in a couple of places, I read the opposite (I have been skimming in lots of places, so don't have links; sorry). I wondered if the latter were just typos, or poorly written, but don't know.
Of course, I've also read that they take lovely images without any modification at all, so it would make sense to get as close as I can to the original.
But another thing I've read is that, at least with the dyalite type lenses, distance is not as critical as with other designs. So, even if I do try to get close, just how close do I need to be? I have some material I could make a shim out of that is 1.5mm thick (nominally; I haven't checked it yet). I imagine that being within 0.05mm (0.002") would be close enough! But what do I know?
I plan to use this lens for contact prints from a 14x17 camera I'm going to build. It's going to be a good year, I think, before the camera is ready, and I'm just curiously reaching out here. Maybe this could clear up some muddiness for others as well.
Bookmarks