Teach me about macro lenses

Macro lenses are designed to have a flat field of focus while most non-macro lenses have a curved  field of focus. This allows for photographing flat objects in while keeping the corners in focus. If you use a non-macro lens you can usually use a small enough aperture to get most flat object in focus. It's just a macro lens does it better.

It is true that refraction sets in at at f8-f11 on a lot of cameras but what a lot of people don't realize is that refraction doesn't soften your images as much as you think. I've found that f22 isn't bad at all and you can make it very sharp with careful sharpening. It's a trade off of sometimes the greater DOF of these smaller apertures offset the softening of refraction to make a better overall shot. You will need to experiment for yourself to see what work best for you.

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Snapshott