I sure liked the color I was getting out of my new, old, used but "like new" Contax C/Y 28-85mm f3.3-4, Zeiss Vario Sonnar zoom lens the other day, but I wasn't too thrilled with the apparent sharpness (or subtle lack thereof) when I really dove in and examined the frames at 1:1 in Lightroom. Even though I am just a humble artist I tried real hard to figure out what an engineer or other technically adept person might do by way of more rigorous testing. I wanted to see if the lens was at fault or if I had mis-set something on the camera to cause an issue. But gosh golly! That kind of analytical thinking comes hard to flighty arts and crafts people so I called to see if there was a "genius bar" at the local camera store, you know, to see if any one had some ideas about, you know, sharpness.
That didn't work out but I was lucky enough to meet some young geniuses up at the swimming pool when the lifeguards cleared the pool of kids at the top of the hour (to do a body count? To let adult swim laps for ten minutes?) I turned to a couple of the five year old dudes who were sitting next to me on the deck and asked their opinions about the whole lens sharpness issue. One of the kids told me he just didn't keep up with the mirrorless products but the other kid, right off the bat, asked me if I'd had the Super Steady Shot feature of the A7ii engaged. I told him that I had. He just shook his head and chuckled. "Look." he said, "I know everyone loves Image Stabilization but it's really a mixed blessing with those old legacy lenses. Especially zooms."
"But why?" I asked.
"Well, because you can't lock in a single appropriate focal length setting for the zooms in the camera menu and that means you are always either over compensating or under compensating with lenses that have no data sharing." The kid adjusted his goggles and snuck another look at the Rolex Submariner Jr. on his wrist. He was anxious to get back in the water.
His friend chimed in: "You also have to consider that with the 4x size of the sensor, compared to smaller sensor cameras, the mass of the moving assembly is harder to control. You'll never get the same results as you would with a smaller format camera; especially one with 5 axis image stabilization." The kids started fidgeting as the clock counted down the seconds till the pool re-opened. I was about to ask about nano acuity (always puzzling for artists but never for engineers and the technically blessed) but the lifeguard blew his whistle and the two kids jumped back into the swimming pool and sped away.
I got up to leave and the lifeguard leaned down toward me from his perch on the lifeguard chair and said, "Sir, I really wouldn't worry about the idea of perfect sharpness, it's an oversold idea in photography, and so much more depends on your focusing technique anyway..." I nodded and grabbed my towel, and I looked for my flip flops because the deck had gotten hot.
As I walked away one of the mom's supervising some of the smaller children in the kiddie pool walked over and said, "I'm sorry to eavesdrop but I had the same problem with a Noctilux and an adapter on an A7sii. You really can't fully trust focus peaking either. Especially with higher res files. Be sure to try punching in the magnification and fine focusing at 10X or more. Then you'll know if it's the lens or your technique. But really, the kids were right about the compromises with legacy lenses and Super Steady Shot. Sometimes I'm just tempted to go back to my Mamiya RZ67..." She gave a little laugh and turned back to smear sunscreen on one of her kiddos.
I'm a bit slow to understand lofty technical ideas so I sat in my car in the parking lot for a few minutes and wrote down what I thought I had learned on an index card. When I got back to the studio I asked a teenager to Google the owner's manual for my camera and read, several times, about how to turn on and off the SSShot. Then I got the teenager to help me set the control to "off" on the camera.
I went out today and tried my whole test over again and I was amazed. The five year old swimmers were right. Turning off the Super Steady Shot was just the ticket. When I look at these images on my monitor, even at 100%, they are just as sharp as they can be.
I hope those two kids are at the pool again some time this week, I have some tax questions I want to run by them.