Originally posted by SCGushue I can't, and won't, argue with those who make statements to the contrary. I do my own testing on every lens I use.
Then it should be a simple matter to produce the test shots that led you to this conclusion. If you can demonstrate this, I'll gladly rescind my statement, as I readily admit I've never performed the test. But it just flies in the face of everything that I have read, experienced, or calculated. Similarly, I've never been to Mars, but overwhelming evidence suggests that it is as science reports it to be.
And as noted, DOF scale markings are format-dependent. Since DOF is also dependent on print size and viewing distance as well as viewer visual acuity, they are also not particularly objective as a measure of the actual optical characteristics of the lens - they are just approximations to mark the DOF that would result from whatever the lens designer decided were "typical" values for those variables.
Quote: in the case of the DA35 it is formulated for a flat DOF from corner to corner and the optics are maximized for macro utilization. As you move away from macro the differences in DOF narrow/over distance, but they are not exactly as a standard 35mm.
It is certainly true that the *shape* of the zone of acceptable focus may differ between macro and non-macro lenses. And due to the curvature of the field in the non-macro lens, it may *apear* to be have more DOF, because objects on the edge of the frame may be in focus at nearer distances than on the flatter field of a macro lens. But you should get corresponding less at the back end on the edge, so the actual DOF should be the same. And even if the corner performance is different due to this curvature, the center DOF should be the same. That's what the theory says, that's what every test I've ever seen show, and that's what your tests have to disprove.