Originally Posted by 2F/2F
Thanks for contributing.
As I understand it, the teleconverter retains the original minimum focus distance of the lens to which it is attached and magnifies the image: the net effect is an enlargement similar to that obtained by an extension tube of the same length as the teleconverter, but without loss of working distance. Whether the image quality is the same for both appears to be a moot point. Both result in light loss.
As far as I know, a diopter lens has the advantage of no light loss.