In article , garciar@san-jose.ate.slb.com says...

>I would appreciate it if anyone having experience with the
>Tokina AT-X 28-135mm f4-4.5 (67mm filt.size) manual zoom would post what
>they think about the optical performance.
>The lens seems to be beatifully built and it is smooth, but how about the
>optics?

I have not used the Tokina version, but the Tamron SP (same specs) is
excellent (strong pincushion distortion at the long end, though....),
and it MUST be used with the very large rubber shade made for it.
They don't make zooms like this anymore, darn! The Tamron SP 28-135mm
is the only wide-range zoom that I have used (that includes the
wide-angle end) that is sharp throughout.
Hope This Helps