Ricoh rikenon p 50mm f/1.7 fast standard prime lens, featuring the pentax k moun

9 The lens is in excellent overall condition, both cosmetically and mechanically. The glass is clean, with only a very small amount of internal dust visible under close inspection, which is completely normal for a vintage lens of this age and does not affect image quality. There is no fungus and no haze. The aperture blades are clean, dry and snappy, opening and closing correctly. The focusing mechanism operates smoothly, and the aperture ring also turns smoothly through its settings. Overall, this is a very clean and well-preserved example of the Ricoh Rikenon P 50mm f/1.7, with excellent optics and smooth mechanical operation. Important Ricoh K-R Mount Warning This lens uses Ricoh’s K-R version of the Pentax K mount. On the rear mount there is an additional small Ricoh program pin, which was originally designed to communicate exposure information with compatible Ricoh film cameras. This is important for anyone considering using the lens on a modern Pentax DSLR. The extra Ricoh pin can potentially enter the autofocus-drive opening on certain Pentax DSLR bodies and become trapped. If this happens, the lens may become physically locked onto the camera and can be very difficult to remove. For this reason, I do not recommend mounting the lens directly onto modern Pentax DSLR bodies unless the user fully understands the Ricoh-pin issue and has taken the appropriate precautions. Excellent for Mirrorless Adaptation For photographers using mirrorless systems, this lens can be an excellent choice. With the appropriate Pentax K-mount adapter, it can be adapted for manual-focus use on systems such as: Sony E Fujifilm X Canon RF Nikon Z Micro Four Thirds Typical mirrorless adapters do not use the Pentax DSLR autofocus-drive mechanism that causes the Ricoh-pin problem, making this lens particularly attractive for adapted manual-focus photography. With its bright f/1.7 maximum aperture, classic 50mm focal length and compact construction, the Rikenon P 50mm f/1.7 is a very enjoyable vintage lens for portraits, everyday photography and creative manual-focus shooting. A beautifully preserved vintage Ricoh prime lens with clean glass, no fungus or haze, clean and responsive aperture blades, and smooth focusing operation.