Re: Nikon Teleconvertor Focal Length

In article <jpq523dclep587gl522qsgeae8uauv0k9u@xxxxxxx>,
ASAAR <caught@xxxxxx> wrote:

On Sun, 15 Apr 2007 20:10:54 -0700, Ockham's Razor wrote:

In other words, if a 1.7 is added to the 70-200 2.8 can it be used at
either 200 or any distance up to 340.

There might be a typo in your question. The question I am assuming that
you are asking is if you can use the TC only for 200 extended to 340, or
if
the whole zoom becomes a usable 119 to 340. Yes, it becomes a 119 to
340mm
f/4.8 zoom. It will not perform as well when zoomed below 200mm as it
would without the TC, though. TCs deteriorate bokeh slightly, may reduce
contrast a little, and lose some light, relative to the same focal length
without the TC.

I do not recognize the typo in my question, but I think you did answer
what I wanted to ask.

The TC is adjustable from no effect to the rated effect (in this case
1.7) when attached between the camera and lens.

Maybe I'm misinterpreting what John wrote, but it looks as if you
think that with the TC mounted, the TC and the lens can be adjusted
to provide any focal length between 70mm and 340mm. My
interpretation is that he is saying that the TC gives you only a
fixed 1.7x magnification, not 1.0x through 1.7x, and so using it
will change the effective focal length of a 70mm-200mm lens to that
of a slower 199mm-340mm lens, and that if you want to use any focal
length between 70mm and 118mm again the TC will have to be removed.
Did I get this right or did I misunderstand both of you? :)

I guess that answers me. The TC is not adjustable in magnification, it
only works as a 1.7 magnifier.

Thanks to all.

--
"When fascism comes to America, it will be wrapped in the flag and
carrying a cross."
Sinclair Lewis
.

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