I've done a quick test comparing the smc Pentax DFA 100mm f2.8 Macro WR with the smc Pentax M 100mm f2.8. This quick unscientific test compares the lenses at long distance because that is my primary use case. I may add more examples later. The photographs were taken with a Pentax K-1 and the lenses were manually focused using live view.
First off physical appearance:
The smc Pentax M 100mm f2.8 is on the left in all samples below. All samples have been processed with identical Rawtherapee settings (capture sharpening, embedded colour profile, auto match curve). White balance was set to auto. Right click (or similar) and open image in new tab to inspect at 1:1
Comparison of colour and rendering stopped down (f16)
Resolution and fine detail at f2.8:
Resolution and fine detail at f8:
Against sun and branches at f2.8:
Against sun and branches at f5.6:
Overview against sun and branches (note tripod shifting on soft ground so above against sun images aren't perfectly comparable)
Interestingly the resolution is pretty much the same. For live view focusing at infinity the dfa 100 macro is understandably difficult. Tiny movements of the rather loose focus ring will change focus by quite a lot. In that respect the M 100mm f2.8 is better suited for tripod use at near infinity distances.
Last edited by house; 03-07-2022 at 12:19 PM.