My 105 2.8 has pretty nice bokeh -- it's no 85 1.4 but still pretty good. Macro rails aren't that good for bugs that move around as they take a while to set up. by the time you micro adjust the camera the bug has moved on.
rw11 wrote:
most macros don't open wide enuff to give a nice blur & bokeh for backgrounds in portrait shooting - but your 85 is fine for that; otherwise a macro esp. the newer ones are xlnt portrait lenses
for products you want an older MF 55 mm macro - as the manual focus is highly desirable and it gives you plenty of working distance
for insect, you want a long focal length so you can not disturb the bug - Nikon no longer makes a zoom or a 200 mm macro - I hear the longer Sigma macros are the best
the R1C1 flash unit will change your life
a macro rail is useful also
if that does not lighten your wallet adequately, I can go on..
in an exact focal length and setup comparison, sure wider aperture lenses will give better OOF areas in the backgrounds, but there's no reason you can't get extremely good bokeh with a macro lens provided you have some control over the environment.
the background OOF blur quality has more to do with the subject position relative to the camera vs subject position relative to the background objects, and focal length, than it does on pure aperture size.
if you can position the subject so that background objects are far out of the focal plane, then the difference between f2.8 and f1.4 with regards to OOF area quality at the same focal length will be pretty minimal.
