RF 100mm Macro - one week review

JayLT4 wrote:

PhotoKhan wrote:

Superior work.

How about focus shift, as reported by TDP?

PK

Thanks!

I read his review of the lens just a couple days ago and saw that he mentioned the focus shift issue. I had not seen this in my use at all, and I did some very informal test shots just to see if I could replicate it with mine. I could not replicate it on my own with my copy of the lens.

I focused on a small part of a flower, at close to minimum focus distance with the lens only (no Raynox or tubes) and took some shots at f/2.8, f/4, f/5.6 and f/8. I saw no appreciable difference in where the lens was focusing.

However, without knowing exactly how they did their testing, one thing to keep in mind is that at those lower apertures, if you're at, or close to, the minimum focus distance of this lens the total DoF is extremely small, so the smallest movement of the camera or subject will be very noticeable. This is also why I always try to shoot at smaller apertures (usually around f/16 for small subjects) . At f/4 the total DoF is around 0.06 of an inch, at 12 inches from the subject.

When I did my very quick test, I was using AF set to One-Shot, and focused right before I took the picture each time, and I was doing it hand-held but with my elbow resting on a table, so fairly stable.

All the issues Ive seen with focus shift have been bad copies of lenses and never seems to be an issue reported by a lot of photographers. Not saying there hasnt been some doosies out there, but I havent seen it.