Pentax SMC Pentax-M 100mm f/4 Macro - Pentax K Mount

The SMC Pentax-M 100mm f/4 Macro is a dedicated macro lens for K-mount cameras, offering a 1:2 magnification ratio. It is praised for its compact, lightweight design compared to faster macro lenses, without sacrificing optical quality. The long focus throw allows for precise adjustments, making it excellent for close-up work, product photography, and as a sharp portrait lens. When buying used, check that the long focus helical operates smoothly across the entire range without sticking. Given its age, internal dust can sometimes accumulate, though this rarely affects image quality. SDS examines the aperture diaphragm for snappy response and ensures the glass is clear of any fungus or balsam separation that can occur in vintage telephoto designs.