Lets eliminate perhaps the obvious... Do you have filters attached to both
lenses and if so are they exactly the same filter?
Then, are you using the proper size filter on each lens so as not to be
restricting light from one over the other?
Are your findings the same with no filters at all?
Are you shooting both lenses at 75 and 25 respectively to take advantage of
maximum aperture on both lenses when doing the comparison? Does either lens
have a hood that could be restricting light?
"Mr.Will" <com> wrote in message