Here we have the Vivitar Series 1 600mm/8 solid catadioptric lens. This was one heck of a find (and a steal) I made years ago. This is hands down *the best* mirror lens ever mass produced for the photography market and contends for the best camera lens made in the USA (With Kodak’s Aero-Ektar IMHO). It was made by Perkin Elmer a sciences and telescope optics company for Vivitar. Most mirror lenses have significant space between the catadioptric elements. This one has none, it is one element. This also makes it very compact and very heavy. Like all mirror lenses this with give you pronounced donut bokeh on out of focus highlights which were a deadly sin just a couple years ago. Opinion might me coming around on that. With the eos adapter, hood, and lens cap it’s still shorter than the long side of an iPhone. Great great great super tele lens. Amazing piece of optical engineering. Heres a couple shot’s I’ve taken with it. It’s a little difficult to work with as it truly requires a tripod and the closest it can focus is 53 feet.