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Sigma AF 180mm f/3.5 EX HSM APO macro - Review / Test Report |
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Lens Reviews -
Canon EOS (APS-C)
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Page 1 of 3
Review by Klaus Schroiff, published March 2006
Special thanks to Christian Mikolaschek for providing this lens!
Introduction
The Sigma AF 180mm f/3.5 EX DG HSM APO macro is the longest of the current set of true
macro lenses in the Sigma lineup. The tested sample was an older variant without
Sigma's new DG coating but most of the findings should be valid for the newer
lens due to the unaltered optical design. It is a full format lens but as
usual we'll have a look how it performs on an APS-C DSLR. Here the
field-of-view of the lens is equivalent to 288mm on full frame cameras. The primary
application of the lens is, obviously, macro photography but as with most macro
lenses infinity focus is possible so its scope is naturally broader.
The optical construction is made of 13 elements in 10 groups with 2 SLD elements.
The aperture mechanism has 9 aperture blades. Typical for most true macro lenses the lens
features a floating system which corrects aberrations down to the max. magnification of 1:1
at a min. focus distance of 0.46m. This relatively long working distance is the major advantage
for macro photography (specifically regarding insects and other nervous critters).
The filter size is 72mm. At 80x182mm it isn't exactly a compact lens anymore nor is it
espeically light weight (965g) but a fair amount of big glass
has to take its toll naturally. Unlike its shorter Sigma macro cousins the lens has
a true IF (Internal Focusing) design so its length remains constant regardless
of the chosen focus distance. The lens features a detachable tripod-ring and a barrel-shaped
hood as well as a soft case are also part of the package.
The construction quality feels very good and as usual the EX ("Excellence")
finish (crinkle style) provides a good grip. The very broad, rubberized focus ring
operates smooth (no wobbling whatsoever) and a little damped - it's doesn't feel
as good as the implementation in the 150mm EX macro though. The AF speed of the
virtually silent HSM drive is pretty good but if the camera decides to hunt throughout
the focus range it can take a while do depending on the application it may be useful
to take advantage of the three-step focus limiter. Full-time manual focusing in
one-shot AF mode is always possible.
The lens is also compatible to Sigma's tele-converters so the focal length can
be pushed to 252mm f/4.5 using the AF 1.4x EX converter (404mm equiv.) and even
360mm f/7 via the AF 2x EX converter (576mm equiv.) - in the latter case you'll
loose AF though.
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