Quote Originally Posted by Jon Ruyle


But if PF from microlens reflections are a function of AOI, wouldn't they, too, improve when stopping down? (Probably not and I'm just being stupid)


Good point. [Edit] The only way that stopping down would be a good test is if the f-number has no relationship to the AOI, but I don't think that is ever the case. There may be some lens designs (reverse tele, I think), where it's at least non-linear, between AOI And f-number, but even then it will at least change by some amount, partially invalidating the test.