Have tested a Vivitar 28-70mm f/3.4-4.8 MC Macro which has a Pentax-K (PK) mount.
Below are some of the test shots taken with this lens.
The B&W pictures are analog and are taken with a Chinon CG-5, AGFA CINEREX (X-ray film) and developed in X-tol.
Color shots are digital and are taken with a Canon 500D with lens mount adapter.
My review has more and hires images and can be found here if you're interested: Vivitar 28-70mm f/3.4-4.8 MC Macro Review
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