Sigma 4.5mm f/2.8 EX DC HSM (Motor-in) Lenses
By George Schaub
March 26, 2008 If you ever want a unique point of view try a “fisheye” lens. Like
looking through a door peephole (which in fact is a “fisheye” type)
this order of lens sacrifices linear correction in favor of a very wide angle
of view. Originally made for creating “full sky” images when pointed
straight up, they had long ago been adopted by photographers for creation of
decidedly different points of view, and, today, even doing QuickTime movies
to display the interior of a condo or vacation home.
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Sigma 4.5mm f/2.8 EX DC HSM (Motor-in) Lenses |
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The fisheye look is an acquired taste, albeit one that has an immediate seductive
quality. While you can correct some of the inherent distortion using various
programs, the point is not to create a “straight” image with a very
wide angle of view but to enjoy the ride of this “beyond peripheral vision”
optic. There are two types of fisheye—one rectilinear, with the standard
rectangular frame and less angle of view—and the other hemispherical,
the type featured in the new lens from Sigma.
One of the truly amazing qualities of the fisheye is the almost ridiculous
depth of field available at even modest apertures. As you know, one of the determinants
of depth of field is the focal length of the lens, and when you use either a
10mm or 4.5mm focal length (with a minimum close focusing distance of 5.3 inches
in both lenses) at even f/8 you get sharpness from 3 feet to infinity with ease.
Add the amazing amount of foreshortening these lenses afford (the seeming enlargement
of close subjects when focused close in relation to the distant background)
the picture possibilities are fairly mind boggling.
Surreal Scenes |
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There’s no question that working with a fisheye can put you
in an odd frame of mind. The low angle sun was hidden behind this
triangular building; note the flare on the black, non-image field,
caused by shooting in very bright light. This did not seem to have
an effect on the image itself. Exposure with the 4.5mm lens was
f/16 at 1/250 at ISO 200.
All Photos © 2008, George Schaub, All Rights Reserved |
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The 4.5mm f/2.8 lens (MSRP $1400, less in many outlets) is said by Sigma to
be the first 180-degree circular fisheye made specifically for APS-C digital
SLRs, and the HSM (motor built into the lens) opens this up for users of those
cameras without built-in lens motors, such as the Nikon D40x used in this test.
Yielding a 180 degree angle of view, the unit is fairly small (3 x 3.1 inches)
and light weight (about 16 oz.) Available in Canon, Nikon and Sigma mounts,
it’s constructed of 13 elements in 9 groups. Being of the DC variety,
it utilizes SLD (special low dispersion) glass and is super coated to minimize
ghosting and flare.
The City at Night |
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A bizarre place often calls for an odd point of view, and this was
amply supplied by the Sigma 4.5mm f/2.8 lens in this shot made in
New York’s Times Square area. The lens encourages you to shoot
at odd angles. Exposure at ISO 640 was f/4 at 1/30 sec. Note flare
in non-image area caused by bright lights. |
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I can attest to that flare-reducing quality as I shot with the lens mostly
at night in and around NYC’s Times Square, a bizarre area that to me matches
up perfectly with the fisheye experience. I worked in a range of ISO 400 to
800 and never had to worry about shake due to the fast f/2.8 max aperture.
The framing certainly is interesting: in fact, if you shoot straight ahead
with the 4.5mm lens, watch out for your shoes appearing in the bottom of the
frame!
Looking Up, and Rectangular
Crop |
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The towering skyscrapers in midtown NYC are made even more impressive,
and somewhat more claustrophobic feeling, when exploiting the severe
barrel distortion of these lenses. Once you start shooting with
a fisheye you get hooked into a decidedly different point of view.
If you want to make a “normal” bordered print out of
it most any software with perspective and distortion control can
do the trick, admittedly creating a smaller file size due to the
cropping that needs to take place. |
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The full report on two new Sigma fisheye lenses, including a 10mm version,
will appear in an upcoming issue of Shutterbug.
Contact: www.sigmaphoto.com
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