The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax DA 55mm F1.4 SDM and the Pentax DFA645 Macro 90mm F2.8 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Pentax DFA645 Macro 90mm F2.8 is the longer of the two lenses at 117mm. The Pentax DA 55mm F1.4 SDM with a length of 66mm, is 51mm shorter. Besides being longer, the Pentax DFA645 Macro 90mm F2.8 also has a larger diameter of 91mm compared to the Pentax DA 55mm F1.4 SDM's 70mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Pentax DA 55mm F1.4 SDM weighs 375g, which means it is 665g (63%) lighter than the Pentax DFA645 Macro 90mm F2.8 which has a weight of 1040g.
Filter Threads
The Pentax DA 55mm F1.4 SDM has a filter size of 58mm whereas the Pentax DFA645 Macro 90mm F2.8 has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Pentax DA 55mm F1.4 SDM:
And these are the 67mm filters that we recommend for the Pentax DFA645 Macro 90mm F2.8:
Lens Mounts
The Pentax DA 55mm F1.4 SDM has the Pentax KAF3 lens mount whereas the Pentax DFA645 Macro 90mm F2.8 has the Pentax 645AF2 lens mount. Some of the latest released cameras that are compatible with these mounts are , and for the Pentax KAF3 Mount and Pentax 645Z, Pentax 645D and for the Pentax 645AF2 Mount.
Focal Range
Pentax DA 55mm F1.4 SDM is a prime lens with fixed focal lenght of 55mm which has an effective (full-frame 35mm equivalent) focal range of
82.5mm when used on a APS-C / DX format camera.
On the other hand, the Pentax DFA645 Macro 90mm F2.8 is a prime lens with fixed focal lenght of 90mm.
