First negative review of the M. Zuiko 60/2.8 Macro

Actually, I think it's possible. I suspect it's a subtle, but possible effect.

Let's look at the statement (as summarised in the OP):

"3) Resolution seems to deteriorate more at high ISO more than it does with some other lenses."

We know high ISO reduces resolution: even without noise reduction the noise replaces detail. Now imagine a lens with 50% detail, and the 60mm outresolving the sensor and giving 100% detail.

If you start destroying detail randomly, you'll lose more detail with the 100% lens than the 50% lens, and a short tele macro will be giving about as much detail as possible. To lose more resolution you need to resolve it in the first place.

Basically I think the reviewer saw a real effect, but you're still correct about him being ignorant. The problem was that he didn't understand what he was seeing, turning a pro into a con.

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