This post is a short description and a few samples from another manual focus vintage lens - the XR Rikenon 50mm f/2.0 S lens sold with several Ricoh SLR cameras during the 1970s and 1980s.
There were apparently several versions of this lens made with different letters following the lens name i.e. 'S' in this case, 'L' and 'P' and also a model without the XR.
I actually have two copies of this lens - both were supplied with Ricoh SLR cameras I bought from eBay, a KR-10 and a KR-10m. One of them was sold as faulty because the focus ring had a very limited movement, but although this was true when I received it, a few twists suddenly freed it up, and it now seems to turn nicely. The other version, which is the one I've used for the samples below, is in very good condition, with no obvious marks or scratches.
In terms of construction, this is a lightweight, plastic lens with a short travel focus ring and an f/2.0 to f/16 aperture range. The lens mount, which is Pentax K is metal however, and there is an auto diaphragm pin to stop down the lens when fitted to the original camera although on my NEX 6 this is not used.
The following are some samples I've taken around the town over the last few days with the f-stop used noted in the instances where I can remember it or wrote it down.
This is one of those lenses which I expected very little of, but I've been very impressed with. Some of the pictures of leaves were taken early in the morning with very little light and with the lens opened fully, and they are showing really good definition and colour across the frame, in the in-focus areas.
Rikenon 50mm f/2 Samples
