>>1151649Most everything you've ever seen has been lenses that are not mirror lenses. Mirror lenses are a bit of a specialty item for the most part. They are very easy to tell apart. They are short and have a big round thing in the center of the front and a donut mirror when you look inside. Their main draw is the fact they are small.
Top pic is a 500mm Mirror lens (catadioptric mirrors lens).
Bottom pic is a 500mm Telephoto lens, the kind you normally see.
You can see why some people opt for the mirror lens.
