Sharpest pic?

I'm shooting with the MP-E 65, and I'm wondering which aperture would give the sharpest picture. I'm guessing maybe f8? I've been shooting at f16, but is that costing me some shapness in the in focus areas? If so, what is the sweet spot of this lens as far as sharpness? Do you give priority to the depth of field and just shoot at f16? What say you?

It depends on your magnification and sensor format. F16 wont cause too much diffraction softening on full frame at 1x, but any higher mag or anything on crop and youll see softening at F16

Brian (LordV) posted some time back all the optimum apertures for the different magnifications.

I loosely follow that guideline when I use mine. Although I keep it at f11 (and down) between 1:1 and 2:1

Drop to f7.1 for 3:1

f6.3 for 4:1

and f5.6 for 5:1

Take care

Martin

Thanks, I'll keep that in mind when shooting.