Thoughts on the DFA 50mm macro

The Pentax DFA 50mm macro is a much lighter and more compact lens than the discontinued FA 50mm macro which I also use. While the FA version is better built in my opinion, from a practical standpoint, the DFA is the easier one to use, being much lighter in weight, a bigger manual focus ring and having the very useful Quick Shift feature that allows manual focus override after AF lock.


K20D DFA 50mm f/2.8 Macro

Some photographers cannot see the point of having AF for a macro lens, but I have found AF usable for magnifications up to 1:2 and for non-closeup shooting like the cat pictured here. The 50mm focal length lens has a useful field of view for a variety of subjects and AF allows quick fuss free focusing. Like the FA version, the DFA can hunt when trying to lock focus, but this is quite normal given the long focus throw of macro lenses. The DFA has a simple slide-on focus clamp when focusing manually.


K20D DFA 50mm f/2.8 Macro

Optically speaking the FA has I think a small edge in terms of sharpness and detail. Both lenses do display some colour fringing at high contrast subjects. Bokeh from both lenses are somewhat similar. The DFA has slightly snappier overall contrast but it also has a little more light falloff at maximum aperture.

The DFA has a floating element design that correct aberrations at closer focusing distances and has a deep plastic hood and given the lens barrel extension at 1:1 magnification, it needs it to protect the front element. Like the somewhat identical DFA 100mm that I also have, the lens performs well but all the Pentax macro lenses still lag behind the superlative and now out of production Voigtlander Apo-Lanthar 125mm f/2.5 SL.