Thanks for the information to confirm my thoughts and the extra info about other graphics formats that might be importable.
I am also very disappointed that modern graphics formats, especially PNG and PDF, are not supported as export/import in Maple. Of course, the Mac OS has all the needed free conversion utilities for TIFF to anything else, and the program from which I am importing supports TIFF export, so the lack of PNG/PDF import/export in Maple is a bother not a show stopper. As a side note, I have to wonder how the TeX/LaTeX export in Maple handles graphics (perhaps as EPS that thereby requires distiller), but this is a subject for a different thread.
As to the references that I might want to preview other symbolic math packages to find what I need (which is not germane to what I asked), our university site license gives me Maple for free, I am mostly quite happy using it, and I've reached the point where learning the nuances of other packages is to be done when it would be required rather than as an adventure down a potential rabbit hole.