So I’ve spent a week with the Canon 100mm USM EF Macro lens on the Sony Alpha A7Riii using a Sigma MC-11 EF-E adapter.

It works. It’s a very workable combination.

The lens does a great job of capturing details, when it’s in focus. When there is enough light and the phase detect sensors are all engaged, the focus is spot on.

Photographed with SONY ILCE-7RM3, Canon EF 100mm f/2.8 Macro USM + Canon EF Adapter (f/2.8, 1/125s, ISO 800) ©WingTangWong

Silent. The focusing mechanism on this lens, being a USM, is pretty quiet. Enough so that it doesn’t draw the attention of my cats. Especially if the camera is in silent mode. The only real gotcha is that when there isn’t enough detail or light, the AF will hunt… and hunt bad. I suspect this is partially the light/signal noise issue but also has to do with the AF stepping mechanisms. When the AF is close to where it needs to be, it can lock on and even lock onto the leading eye. So it’s a serviceable lens on the A7Riii, but a native macro lens would probably be better.

Photographed with SONY ILCE-7RM3, Canon EF 100mm f/2.8 Macro USM + Canon EF Adapter (f/4.0, 1/320s, ISO 400) ©WingTangWong

While I complain about the AF, I also found it to be quite a fun lens to use. The color rendition is definitely “Canon” and not “Sony” or “Minolta”. I found myself “tweaking” the color rendition to be more like the Minolta colors that I love. But the details that the lens is able to capture are definitely a win. Gotchas? The edge details, there is some chroma shifting due to the curvature and closeness of the subject, especially when the distance between the lens and the subject is in the 6″-10″ range. But if you’re aware of this going in, it’s something you can plan your shot around.

Oh, one thing I noticed when processing the images, uncompressed RAW vs Jpeg, there was a huge difference when it came to detail recovery. Definitely got some serious benefits from being able to process the images from the RAW(s).

Photographed with SONY ILCE-7RM3, Canon EF 100mm f/2.8 Macro USM + Canon EF Adapter (f/4.0, 1/160s, ISO 250) ©WingTangWong

Yeah, 42MP + 100mm Macro lens… there is a good deal of delicious details to be had.

This wraps up this “week with” series of posts for the Canon 100mm USM Macro EF lens.