> "Mr. Bill" <[EMAIL PROTECTED]> wrote:
> My EF 80-200mm f2.8 L has a minimum focusing distance of 1.8m.
> When I put on the 500D, the MAXIMUM focusing distance becomes
> much less than 1.8m, so I've lost the distance between this new
> maximum and the old minimum. I want to smoothly continue the
> focusing distance without any gaps beyond the standard minimum
> distance.
Hi Bill,
What an interesting question. Fortunately, there are lots of
answers, or none at all, depending on what is acceptable to you.
In my lens calculator, I added the math for extension tubes and
teleconvertors (again): http://members.home.net/jul.loke/
If the formulae are correct, this is what should happen if you
add a short extension tube. e.g. 12mm which will produce
the following theoretical (calculated) results:
focal length, focus range with 12mm tube, angle of view
80mm, 0.46-0.61m, 26.5 degrees
100mm, 0.61-0.93m, 21.9 degrees
135mm, 0.83-1.65m, 16.7 degrees
180mm, 1.02-2.88m, 12.9 degrees
200mm, 1.08-3.53m, 11.7 degrees
Can you Get/Rent/Buy another lens e.g. a bag of prime lenses,
or the newer EF 70-200 L zooms, or even the EF or other 28-200 (!)
which go down to 50cm at all focal lengths :-)
Perhaps even the fabled 70-180 f/4.5-5.6D AF ED Micro Zoom Nikkor
http://nikonusa.com/usa%5Fproduct/product.jsp?cat=1&grp=5&productNr=1983NAS
which is supposed to be able to focus to 1:1.32
So, you can choose lens mount, aperture range, focus range,
choice of magnification/angle of view, but not all simultaneously.
Isn't life interesting?
Cheers
Julian Loke
*
****
*******
***********************************************************
* For list instructions, including unsubscribe, see:
* http://www.a1.nl/phomepag/markerink/eos_list.htm
***********************************************************
