There was once a British made drop-plate camera located in Greece in which I had an interest. But, there was something fishy looking about the front of the lens that kept me wondering. I then asked the vendor several times about the lens and received replies that made no logical sense. I guess it was either the language barrier, or intentional. So, ultimately I passed on the camera. Eventually, and well after the camera sold, I found a catalog showing how the camera should look if it was complete. It was then that I knew the front lens elements were missing completely. Having a good sense of what does, and doesn't look correct is helpful. Sometimes the defects are not so obvious.