SMC Pentax K 28mm f/3.5 on NEX 3, Quick Review
How does this cult classic wide-standard lens perform on modern APS-C Cameras?
This lens has a reputation from various forums as being an excellent performer. Here is a quick review of the lens.
The build quality of this lens is excellent as with all the original K mount lenses, it is also relatively large and heavy because of this. The later M lenses made an effort to miniaturize the existing primes, but they lost the substantial feel of the older Takumars when they did that.
The lens has 8 elements in 7 groups, with a 5 slightly curved bladed diaphragm. The minimum focus distance is good at 0.3 m (1 ft), which is fairly typical for this class of lens, and it is hefty at 261 g (9.2 oz). It uses standard older K filters of 52 mm.
Comments on the Results
Center sharpness is very good wide open, but does drop off towards the corners. The resolution is relatively good across the frame at all apertures.
Distortion is fairly good for the focal length at -0.87% barrel (numeric average for all apertures).
Lateral CA is very good, better than average for the class of lens.
Pros and Cons
- Center performance at all apertures
- Entire frame from f/5.6
- Build Quality
- Large and Heavy
- Small Max Aperture