"Ken
Cashion" <kcashion@datasync.com> wrote in message
news:3f6e346e.43390200@news.datasync.com...
> On
Sun, 21 Sep 2003 23:26:56 GMT, "Jeremy"
<jeremy@no-spam-thanks.com>
>
wrote:
>
>x-no-archive: yes
>
><nielsenp@in.com.au> wrote in message
>
>news:j88smv47k4c1arih0hc7k5ft48rd3f8ojg@4ax.com...
>
>> I have an OM2 with a Zuiko 50mm. I have the opportunity of buying a
>
>> Makinon 2X converter, giving me a lightweight 100mm option.
>
>>
>
>> Would there be any significant difference in print quality between
>
>> this combination and, for example, a single 100mm lens of similar
>
>> quality to the Makinon?
>
>>
>
>> I suppose what I am asking is what, if any, are the detracting
>
>> features of teleconverters over a single lens of similar focal length
>
>> and brand.
>
>>
>
>> And ... are there any circumstances in which the above disadvantages
>
>> would be more pronounced.
>
>>
>
>> Thanks for your reply.
>
>>
>
>> Peter Nielsen
>
>You'll certainly lose some resolution.
Depending upon how the degree of
>
>enlargement, and your tolerance for the reduced resolution, you may be able
>
>to accept the quality degredation.
>
>
>
>Teleconverters don't really give you another lens--there is a trade off,
and
>
>they are best utilized if you are using them only rarely--to have a focal
>
>length available to you that you would not ordinarily use.
>
>
>
>I would consider using a good prime lens with a teleconverter as an
>
>alternative to buying a cheapie lens of a larger focal length, used without
>
>a teleconverter.
>
>
>
>I carry one myself--but I use it only a few times a year. You will need to
>
>try it out, look at the results, and determine whether the results are
>
>acceptable to you.
>
And I agree with Jeremy. I have a good
2x and have used it
>
with good fixed lenses. The quality is
always down to the point that
> I
can tell it almost as soon as the slide goes on the screen. It is
>
less obvious in a wall full of prints.
>
With my 28mm, I have 56mm, but why would
I use it for 56mm
>
when I would get a superior image from a fixed 50mm? I have a 35mm
>
and it will give me a 70mm which is a nice step between my 55mm and
> my
fixed 135mm.
>
It, with the 135mm is how I generally have used it. This is
>
much easier than carrying a 250mm for the few occasions when I would
>
enjoy one. So for this sort of
application, it is fine.
Teleconverters
can be more useful than at first apparent.
With my
28mm f2.8 AIS Nikkor, I can use its sharp very
close
focusing image with a good 2X converter to get a fairly
good
macro lens; with my 16mm fisheye used with a good
1.4X
converter, I get a very sharp, very wide lens that is
more
kind to rounded forms like people at the frame edges
(and to
verticals of distant buildings) than a standard super-wide
is;
with a round 8mm fisheye, a 1.4X can be used to enlarge
detail
without loss of hgorizontal angle of coverage; with flash
macro
work, I can increase magnification with no apparent
losses;
with my fast 80-200 f2.8 zoom, a good 1.4X makes
it go
to 280mm with little loss in quality (particularly if stopped
down
one stop); with my 85mm f1.8 or 2, I get a pair of FLs
with
the addition of a very compact 1.4X; with long, fast teles,
one
lens can become the basis of a three-lens set with the
addition
of good 1.4X and 2X converters (and in some cases,
these
can be combined, for a fourth FL); with a PC lens, the
displacement
is multiplied by the power of the converter,
permitting
otherwise impossible perspectives (like placing the
horizon
line outside the frame while maintaining alignment
with a
tall building). Also, converters tend to remove linear
distortions
from lenses, which improves one aspect of the
performance
of some lenses. With the best converters,
combined
with good lenses that are compatible, generally
stopping
down to f4-5.6 is required with a 1.4X for good
results,
and to f5.6-8 with a 2X - but to these stops must
be
added the one stop loss of the 1.4X and the two stop
loss of
the 2X...
--
David Ruether
d_ruether@hotmail.com
http://www.David-Ruether-Photography.com