Quote Originally Posted by BrianShaw View Post
That is a problem. Information like that is available but one must read and understand the specification data for the lens in question. Knowing if your lens is a telephoto design or not is essential to knowing this.
I highly doubt any of my lenses are telephoto's, even if I bought a "telephoto", it wouldn't be a real one per your specification that the link has to be longer than the extension or something like that.

I own a 75mm f/4.5 grandagon, a 90mm f/9 Schneider super angulon and a 150mm f/5.6 Schneider super angulon, and I plan to purchase a fujinon 300mm f/8.5 C lens to complete my "kit" but the 300 is a compact lens so I don't think that qualifies as a telefoto in your new-to-me definition.