>
> Your comment about the TC-16A is very interesting.
> While I don't doubt what you say, I've never heard
> this comment about the focus displacement from
> anyone else. Have you ever tried a different body
> or converter?
I haven't tried it with my F4 because it's got an IR
filter in it, so it won't focus with anything slower
than about f4. I'll take the filter out and see what
it does.
> Given you admission to pickiness, would you say
> this effect is so small that others wouldn't notice
> it?
Maybe. You couldn't see it in a 4x5 print, and might
not notice it in a 5x7, but it's pretty obvious in
an 8x10.
I first noticed it after I shot some pictures of ducks
on a pond using the 300mm/f2.8 both with and without the
TC-16. I actually got better results by enlarging the
non-TC negatives 16x than by enlarging the ones with the
TC 8x.
So, I put the TC and lens together and went out to see
if I could figure out what went wrong. That's when I
found out that the TC would re-focus closer after I'd
already focused the lens where it should be.
-Don
