I'm not arguing Ted other than maybe the practicalities of perfect camera lenses even at F11. One day I will figure out a way of measuring their performance accurately but I'm not going to stick resolution targets on the fence at the bottom of the garden again as I am more interested in how they perform when I take a photo and to me diffraction effects don't really figure not spot sized ones anyway. However I feel the need for a test coming on. It's more feasible with mirrorless.
John
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