In article <4g27ra$stl@kira.cc.uakron.edu>, r1eb@dax.cc.uakron.edu says... (.... about 90-180mm f4.5 Series I)

>I've only seen the 90-180 macro, never
>used it, and it's huge: twice the length and weight of the 90 macro,
>which is itself a substantial hunk of glass. The 90-180 is a >flat-field macro, if I'm recalling correctly. It has something like
>18 elements and provides continuous focusing from infinity down to 1:2 >at all focal lengths. Anybody ever used one?
>Eric Birdsall

Yes, I tried one (surprise!), and based on that experience, I have
never figured out what the appeal is of a zoom lens of average quality
optical performance in a truly large and heavy package with a very moderate 2x zoom range combined with a really fast ;-) f4.5 aperture!
The 75-150mm f3.5 E series Nikkor has about the same coverage, but is far smaller, far lighter, almost a stop faster, and considerably
sharper than the Vivitar. I guess if you MUST have a zoom macro lens,
this lens MAY be justifiable.....
Hope This Helps