Hi,
>> e-sif page and it turns out that the left side numbers
>> (i.e. focused at "infinity") are pretty accurate, but the
>> min. distance focusing numbers are quite off.
> The Olympus charts assume that you are using the approximate
> 7mm of extension available in the focusing mounts of each
> Zuiko lens in the 50mm range. So if you factor in another
> 7mm of extension into your figures everything should agree.
Well, I came to the results using a magnification factor which I deduced
from my own measurements made at infinity and at min. focusing distance.
Therefore, the first factor (infinity) didn't include the 7mm in the
calculation, but the other one (i.e. min. focusing) did, as it was derived
from measurements where the lens had been put at min. focus, and hence
included the additional 7mm....
Ah, did you read Chris Riek's message? That one has a very handy method for
determining the magnification ranges. Apparently you can just divide the
focal length of the lens by the extension added for the infinity setting,
and do the same (with an added 7mm for the 50/1.8 lens) for the min. focus
distance to quickly determine the actual range...
Cheers!
Olaf
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