Teach me about macro lenses

Well, I don't understand having to shoot crop sensor. I mean, I've shot macros with a 4X5 and it seemed to work OK. And you don't need f/anything. Sometimes stopping down is OK, sometimes it isn't. Here's a shot at about 2:1:



2:1 macro at f/16 nominal, f/40 actual

Canon doesn't report effective aperture. The lens was set to f/16, which is about f/40 at 2:1 magnification. But the picture is OK. Look at the original, however, and you can see it's soft.

So I stacked 20 images at f/3.5 indicated, or f/9 actual. This one actually is sharp:



2:1 macro at f/3.5 nominal, f/9 actual. 20 images at 20 micron increments, stacked.

So stacking does give you better results but it's often unnecessary.

--
Leonard Migliore