Reader's Comments - Index of - Free

Macro Photography
Macro zoom lenses are not macro lenses. They don't allow significantly greater magnification than a 50mm normal lens and they
deliver low quality.
Macro Lenses
What you want is a macro lens. Fortunately, it is difficult to buy a bad macro lens. This is
kind of odd in a world where 90% of the lenses sold are bad. Here's my theory: Every day
at least one man wakes up and says to himself "I have a 1.5 inch long penis; I think I will
buy a big SLR like a pro. But I don't want to spend money on frills like lenses so I'll get a
Tokina zoom." However, no man ever wakes up and says to himself "I have a 1.5 inch long
penis. I think I will buy a macro lens so that I can make a 1:1 photograph of my penis and
distribute this photo from my Web server. But I don't want to spend too much on this lens
so I'll try to find a cheap Sigma."
In short, anyone in the market for a macro lens is already fairly sophisticated and quality
conscious. If you read USENET then you know that the world is full of people asking "is this $150 Tamron 75-300 zoom as good as a
$900 Nikon 300 prime?" Can you blame Tamron/Tokina/Sigma for trying to separate people like this from their $150? But there isn't
apparently a big enough collection of fools in the market for macro lenses to support a junky macro lens subcategory.
In my humble opinion, the best macro lenses are the latest autofocus mount models made by Nikon (my primary 35mm system is
Canon EOS, by the way). Nikon makes 60mm, 105mm and 200mm focal lengths. Each lens will focus continuously from infinity to
1:1. You can shoot the moon and capture the bear claw without stopping to change lenses or screw in filters. How do these lenses work?
Do they just have a much longer helical than the 50mm normal lens? Yes and no.
Yes a macro lens helical has much more travel than a normal lens helical. You can watch the front element move an inch or two.
However, these helicals aren't just pushing a stack of glass back and forth like the 50mm's helical. Inside one of the elements is moving
("floating") so that the optical design changes to a more appropriate one for close-up photography. Thus you get sharp images at all
focussed distances.
How do you choose a focal length? The same way you do with a non-macro lens. If you can't get very close to your subject at a soccer
game, you don't pull out a 50mm lens; you get a 300. If you can't get close to an insect without it getting scared and flying away, then
you want the 200mm lens and not the 50. If you want to compress features in a woman's face, you don't get a 28mm lens; you get a
105mm lens. It is the same with macro work; longer lenses give you a flatter perspective.
What about other companies? Canon makes 50, 100, and 180mm macro lenses. All three incorporate floating
elements. The 50 is cheap but it only goes to 1:2 without a "life size converter" (sort of like a telextender) that
you stick between the lens and the camera. The 50 is also annoying because it has the ancient non-USM
Canon motor. So it can't do simultaneous AF and MF like the ring-USM lenses. The 100 goes to 1:1 but also
has the old-style motor. The 180/3.5 is a new design with three low dispersion elements, a tripod mount, and
USM for full-time manual focus. It is also compatible with the Canon telextenders. At right, you can see
about as close as one can get with the Canon 50 (from my Christina page; part of the reason that photo.net is
banned by most of the Net censorship services).
Tamron makes a newish 90/2.8 macro lens that goes to 1:1. It is probably pretty good.
http://www.photo.net/macro/primer (3 of 8)15/11/2004 6:47:08 PM