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macros and close-up "filters"

 
 
Paul Rubin
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      01-02-2007
"Joseph Meehan" <(E-Mail Removed)> writes:
> As for "Closeup lenses have significantly more effect when used in front
> of a *longer* lense:" "more" is not always better. For the needs of the OP,
> I would guess the potential for greater magnification when using longer
> lenses is not likely to be useful. For the nature photographer, then the
> added working distance and possible additional magnification could be of
> value.


I think the point is that a close-up lens on a telephoto lets you fill
the frame with a smaller object than the same close-up lens on a
normal lens. Tell me if I got the following right, since I sort of
made it up as I went along.

Example: you have two lenses, a 200mm lens that focuses down to 2
meters, and a 50mm lens that focuses down to 0.5 meters. Either of
these will fill the frame with roughly the same sized object, around
40cm (based on full frame 35mm sensor).

Now suppose you have a +2 diopter close-up accessory filter. Your
200mm lens with no filter focuses to 2 meters (0.5 diopter) and the +2
close-up filter makes it focus to 2.5 diopters or 0.4 meters. Your
50mm lens focuses to 0.5 meters (2 diopters) and the +2 filter brings
it to 4 diopters (0.25 meters). That means the 200mm lens with the
filter can now fill the frame with a 7 cm object, while the 50mm lens
with the filter can fill the frame with a 20 cm object.

That's why we say that the close-up filter is more effective on a
longer lens.
 
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tomm42
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      01-02-2007


On Jan 1, 5:49 pm, Tony Belding <(E-Mail Removed)> wrote:
> Just wondering if somebody could help me sort out the pluses and
> minuses of a real (i.e. expensive) macro lens, as compared with the
> close-up lenses that thread on like a filter? I notice there are cheap
> close-up sets with different diopter strengths, and I also noticed
> there are two-element close-up lenses which cost more. . .
>
> I'm interested mainly in product shooting (such as, for eBay) where I
> want decent-looking results, but not trying to count the grains of
> pollen stuck to a honeybee. I was thinking a close-up "filter" on a
> regular 50mm or 135mm lens would probably be good enough for my
> purposes, is that a fair guess?
>
> --
> Tony Belding, Hamilton Texas


Nothing beats a macro lens for closeup photography. In fact macros are
such over all good lenses they are nice for general photography too. I
use Nikon cameras a bought an excellent 55mm Nikkor micro (Nikon's
macro) for about $200 on Ebay. This would be a great lens for product
shots. If you have a lot of smaller items a longer focal macro makes
lighting easier so look for a 100mm or so, again you save by buying
used. The nice thing about macros is that it is hard to get a bad lens
unless it is damaged in some way. Even lowly Vivitar lenses have decent
macros. If you feel comfortable not using autofocus, manual focus
macros can be an excellent buy used (at high magnifications 1:1 or 1:2
manual focus should be used anyway).
Diopter lenses are bad at their worst and useable at their best. The
muli lens achromat adapters being the best. But you can get a used
macro lens for the same price.
There are other ways to get closeups, reversing lenses, bellows or
extension tubes. All of which work but require some photo savvy, and a
lot of testing, which sure is easier on digital than film.

Tom

 
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Don Stauffer in Minnesota
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      01-02-2007

Tony Belding wrote:
> Just wondering if somebody could help me sort out the pluses and
> minuses of a real (i.e. expensive) macro lens, as compared with the
> close-up lenses that thread on like a filter? I notice there are cheap
> close-up sets with different diopter strengths, and I also noticed
> there are two-element close-up lenses which cost more. . .
>
> I'm interested mainly in product shooting (such as, for eBay) where I
> want decent-looking results, but not trying to count the grains of
> pollen stuck to a honeybee. I was thinking a close-up "filter" on a
> regular 50mm or 135mm lens would probably be good enough for my
> purposes, is that a fair guess?
>
> --
> Tony Belding, Hamilton Texas


These work well. I use them in preference to the macro function on my
lens. It is a matter of perspective. Many "macro" zoom lenses are
macro only at the longest telephoto focal length. This means you shoot
from further away than with the plus lenses and a 50 mm lens. In fact,
when I use the plus lenses on my zoom, I use the 50mm position.

Now, if the product you are shooting isn't one where you worry about
the apparent size of the product, it wouldn't make a difference. But
the use of a supplemental (plus or closeup) lens does tend to make the
object look bigger and more massive.

 
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Floyd L. Davidson
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      01-02-2007
Tony Belding <(E-Mail Removed)> wrote:
>I'm interested mainly in product shooting (such as, for eBay)
>where I want decent-looking results, but not trying to count the
>grains of pollen stuck to a honeybee.


Tony, that is the key to your question. I'm just like everyone
else and can go on for pages and pages telling you about
wonderful ways to do photomacrography, but all of it ignores
what you want to do!

For eBay you don't want 10Mp images. 600x800 is probably the
biggest you should use! Details about why achromatic close-up
lenses are better, and dedicated macro lenses are best, are
pointless.

Go to eBay and do a search on "fotodiox close-up" and close-up
sets in 67mm, 58mm, 55mm and 52mm. They also sell stepping rings
for any size. Choose the size that fits your 135mm telephoto,
or the next size larger. Then get step-up rings as necessary
to fit both the 135mm and the 50mm lenses. Or just buy two
sets, one for each lense...

>"filter" on a regular 50mm or 135mm lens would probably be good
>enough for my purposes, is that a fair guess?


If you get to having too much fun, and just want to have the
technical ability to do great photomacrography, buy a 105mm
fixed focal length macro lense. There are used manual focus
bargains and there are brand new auto focus lenses too. It
happens that a good 105mm macro lense is a well understood
design and virtually *every* manufacture makes a tack sharp
version. But come back and post a question about those lenses
before you buy! Rest assured we can regale you with hours of
delightful arguments about which one is the right one...

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) http://www.velocityreviews.com/forums/(E-Mail Removed)
 
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