Amazon.com Product Description
Sigma's 180mm F3.5 EX IF HSM macro lens lets you take life-size, 1:1 images without the use of accessories. When shooting at this magnification, you can be a full 18.1 inches from your subject, ideal when your subject may be easily disturbed. In addition to the life-size images, this lens also uses the silent HSM (hyper-sonic motor) so you can truly capture those hard-to-get images without disturbing your surroundings or subject.
The apochromatic design of the optics, combined with two SLD (special low dispersion) glass elements, plus a floating inner-focus system, help control chromatic and spherical aberrations as well as astigmatism, optical problems that often effect the quality of your images. This effect gives you high-quality performance across the entire focusing range. This model is dedicated to Canon AF SLR cameras.
Product Description
Taking picture of small animals and insects can be difficult, because they often run or fly away, or can be dangerous or become aggressive if you approach them. Therefore it is advantageous to have a greater working distance between the camera and such subjects. Longer focal length lens can provide this greater distance, but most long lens do not focus close enough to provide a large image of small subjects. The tele-macro type lens solves this problem by producing a large, high quality image, up to life-size, while maintaining a long working distance. This can enable you to capture on film the world of photomicrography, without disturbing the subjects. The 180mm F3.5 APO MACRO lens has a very narrow field of view, and can allow very narrow depth-of-field for selective focus and less distracting backgrounds. This lens is most desirable for photographers who are serious about producing high quality images both of macro subjects at life-size reproduction, as well as normal telephotography.