Despite the fact that Ricoh has overused the “500″ moniker I love the uniqueness of this particular camera. The film advance lever is located underneath instead of the more traditional right thumb location. Being entirely a manual camera exposure levels need to be determined with a light meter or other means. Rather that seeing this as detrimental I actually think that this helps the photographer to really consider what they are perceiving. You need to put some conscious effort into the making of the image.
If you look at the bottom of the camera you can see that there are two locks on either side that secure the back and bottom plate to the rest of the camera. The back must be removed for loading and unloading the film. Inside I’ve circled the two cams that interlock in order to advance the film. The bottom one is made from spring steel in such a way that it advances the film one way but slips over the other one when returning the advance lever. When I first received this camera this mechanism was not working but simply bending the spring steel cam by a fraction of a millimeter, so the two cams met, brought it back into operation. Another thing with this camera was that the focus mechanism was frozen. I carefully applied a small amount of constant force be hand until the hardened grease loosened up. Then by turning the focus numerous times the focus became smooth and even, while it is a bit stiff it could be described as nicely dampened. The reason I mention these things is that the first response to a non functioning camera shouldn’t be to rashly disassemble but to spend time with it and figure out what isn’t working and why.