(The following is an approximation of someone's remembrances)
Originally Posted by Bill Burk
"When I started working for Adams, I looked through the folders of prints he had under a table. I thought I would be in for a treat, savoring delights unseen by the public. There were a lot of very ordinary photographs. Adams came up behind me and said, 'Well, I only get a good one maybe once or twice a month.'"
I don't think that Adams meant the quote for photoclub amateurs, but for the professional creators of "fine art." Those guys, that lot there.
Now, back to the original thread premise. Photography was never pursued in my family, and many years down the road I bought a not-so-bad Pentax WR90 P&S after something I bought in a blister pack died. Was the P&S good? For the most part, it was excellent. It only failed when the subject was backlit by the sun (major flare) or if I wanted to not do something point-and-shootey. So the next camera was a Pentax 6x7. I figured that if I was going to step up, it was going to be something larger. It was a good choice, and I still have that camera. I went up to 4x5 when I kept having to stop down way too much for things to get into reasonable focus. Yes, I wanted movements. Later on I bought an 8x10 Cambo SC. Yep, Big Film Syndrome!
I also have a Pen-F half-frame camera, which is my smallest. The lenses are sharp, and I enjoy the camera imensely. I like the way photographs look both sharp and soft at the same time, with ISO400 film. But is that the limit? No, not really. I have attached two crops. These are from an 8x10 Ilford Delta 100 negative, and the crop area is about the size of a Minox negative. The lens used was a Wollensak 6-1/4" (159mm), stopped all the way down to f/45 for grins and giggles. The final crop (my avatar image here) is about 2mm x 2mm. From a lens manufactured about 1935.
So: what's the lower limit of image quality? You can recognize something in it, and that's good enough. What's the upper limit? You recognize far too much.