"Bolo" wrote:
>The MF macro lenses that I've looked at all go down to 1:2. After
>that you need extension tubes for 1:1. That is well and fine. However,
>I've noticed that almost all of the AF macro lenses that I've looked
>at tend to go to 1:1 ... without extension tubes. Presumbably this
>is because the rack&pinion and/or IF mechanisms allow a greater
>a bit more freedom in lens design than the helicoid does.
I've heard that internal focusing lens designs that go to macro distances
do so by changing focal length. It would not suprise me to find that the
autofocus macros that go to 1:1 do exactly this. Doing so subtly affects
the perspective that you get on film and, perhaps more importantly, affects
the _background_ you get with the macro shot (unless you shoot all macros
with flash). It is pretty much up to you to decide if that matters to you,
however, for a first macro lens, I don't think I'd worry about it myself.
>I've not settled upon a focal length for a macro lens; my first
>guess is 100 mm, since I already have a 50mm, and I'd like some
>additional stand-off than I have now. I've looked idly at macro
>lenses. Comments on this list seem to indicate that the FA 200mm
>macro is even a *better* lens than the awesomely rated A* 200mm
>macro, so quality doesn't seem to be an issue with the AF macros.
100mm or thereabounts would be my first recommendation. Not too expensive
but with enough working distance to open up a world of macro photography to
you that a 50mm might be hard pressed to achieve. Also, that range will
leave some background detail without going to the extremes of providing too
much distracting detail or completely devoid of detail. The 200mm macro is
a different beast and you'll get very different backgrounds -- wanna see
some, take a look through Shaw's Closeups In Nature book. Most of the shots
with no background detail other than indiscinct blobs of color were done
with a 200mm macro.
>Since the AF lenses goto 1:1 without a extension tube, is there
>something which you lose with a 1:1 AF macro lens compared to a
>traditional MF Macro lens? Besides requring a lot of extension
>tubes to get to 1:1 with the longer MF macro lenses?
Um.. assuming you use the lens in AF mode for macro shots, you loose the
ability to compose the part of the subject you want in focus on anywhere
other than directly under the sensor. Using AF also may cause you to
sacrifice some of the scant DOF you have -- you can't focus slightly past a
subject to add a little more detail to the background while not loosing too
much detail on the subject. With a AF lens, you also give up the ability to
use trap focus.
"Mark Erickson" wrote:
>In terms of utility, AF lenses enable autofocus,
>and MF lenses do not. For carefully-composed
>images, you may not miss the AF. If you're out
>in the fields chasing insects, AF may enable you
>to get shots that you would otherwise miss.
AF probably won't enable you to shoot insects. I generally rely on a MF
lens and trap focus mode. I hand-hold a lot of my insect shots and you
almost can't tell (they are still a darn sight sharper than a lot of what I
see in publications).
Yes, with a 100mm macro you may not be able to stalk hoverflies (seem to
need a 200mm for that), but everything else will be within your grasp,
including the ever popular dragonflies and butterflies.
>In terms of magnification, here's a quick table:
> SMC-A* 200mm F4.0 Macro: 1.0x
I thought mine only when to 1:2 mag. Oh well, guess I'll have to take a
look at it when I get home tonight.
>I bought my A* 200 a couple of years ago from B&H for $950.
>The FA* 200mm F4 Macro goes for $1350 at B&H. That's
>quite a price hike!
The A 200mm f/4 macro I have has inteference problems with the Pz-1p
body -- the tripod mount bumps into the RTF housing when mounting (I can
hear y'all out there saying "awwwww" :-). Not a major problem, but if the
FA version corrects this without compromising on the optics, then it is
probably the better option to consider. I'd consider trading up, but it
really isn't much of a problem and besides, I like that lens too much to
part with it.
hope that helps,
patbob ([EMAIL PROTECTED])
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