In article <4hlr8v$5ld@duey.gte.net>, anchored@gte.net says...
[..]
>The one lens that is not a Canon brand is a Vivitar Series 1 90mm f2.5
>macro with matched multiplier (bought in the late 1970's). Of all my
>lens, this is possibly the sharpest FD lens that I possess. [..]
>I understand that this was one of Vivitar's "best-ever" lens, but it's
>been discontinued for many years. How are other Series 1 lens rated? (I
>probably would never consider a standard Vivitar!) [...]

The 100mm f2.8 Series I macro (also, in the early version, a "Kiron",
I think) was also excellent, and did not have the fatal flaw of the
otherwise excellent 90mm: flare when used at non-macro distances.
I have tried several samples of the Series I 90mm, and the flare
(even with VERY deep shades) was insufferable. I have not been fond
of the other Series I's that I have tried (28-90, 28-105, some samples of the 70-210 versions [some were good], and the 100-500) - and I have not tried the 35-85, 28, 135, 200, or mirror Series I's, or the very recent offerings (better hurry - they tend to stay on the market but briefly ;-).
Hope This Helps