Dear Daniel
Yes, macros seem to zoom, but the focal length (usually) doesn't
change, just the angle covered, which is half the original angle at
1:1. Lenses with floating elements may vary!
Tom
On Friday, September 14, 2001 at 15:42, Daniel J. Mitchell
<olympus@xxxxxxxxxxxxxxx>
wrote on "[OM] Macro lens question," saying..
> I've just acquired a Vivitar 55/2.8 macro lens; it focusses down to 1:1
> very nicely, not got any prints done yet so I can't comment on sharpness
> (and it takes yet _another_ different filter size, rassafrassin..).
>
> However, when I focus it in, it also zooms -- a quick check shows that
> focussed at infinity, I get an image roughly three-and-a-half times smaller
> than the image focussed at 21cm (=1:1, given that the lens is pretty
> extended by that point). (tested this by pointing at the keyboard focussed
> at infinity, counting the (blurred) keys, got seven; focus all the way to
> close, now I can see two keys).
>
> Is this something I should expect? Does the Zuiko 50/3.5 do this? (a quick
> check of the 50/1.4 and a generic zoom suggests that they _do_ change
> magnification with focus, but nothing like as much as for the macro lens).
------------------------------------- No spam, please
Tom A. Trottier (after 2001 Oct 14)
415-400 Slater St. 758 Albert St,
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