Product Description

The Sigma 105mm f2.8 EX Macro delivers superb, distortion-free images throughout its broad focus range, from infinity telephoto to 1: 1 (life-size) macro, as close as 12.3" without accessories.Its non-rotating front lens group makes it easier to work with polarizing filters and has a focus limiter (eg. Full Range; - 15.8 in.; 14.6 in. - 12.3 in.).A "focus-free" mechanical design allows the lens to auto focus without any interference from the manual focus ring. This makes it easier to hold the lens without affecting the speed or normal operation of the autofocus function. Rugged mechanical construction also makes it durable enough for even the heaviest use required by professional photographers.The Sigma 105mm f2.8 EX Macro features the new deluxe external EX finish. These features and other Sigma optical advances, including an uncommonly broad range of focus, make this an ideal lens for a wide variety of applications, from nature photography to portraits.A handy screw-in type metal sunshade makes it easier to rotate a polarizing filter.

Product Details

• Brand: Sigma
• Model: B0002P19XA
• Dimensions: 3.10" h x 4.00" w x 4.00" l, .99 pounds

Features

• Super Multi Coating reduces flare and ghosting that tends to occur when using digital SLR cameras
• High performance medium telephoto macro lens optimized for digital cameras
• Lens Construction - 11 Elements in 10 Groups
• 12.3 (31.3cm) Minimum Focusing Distance
• Dimensions - Diameter 2.9 x Length 3.8 (74x97.5mm)

Customer Reviews

Will satisfy your most basic needs for macrotography
Overall , the image quality is very good -- the sharpness is undeniably good. I'm no sucker for the techy terms but my most qualified review of the photos is -- I am very satisfied with the quality.

Downside - the AF motor is very slow. And MF is a bit mystery to me. I could not control the focusing during MF. Normally, I just move the switch to MF to lock on the subject and that's after focusing with the AF. I could not move the zoom range using MF (i must be doing something wrong ... or the instruction in the manual is not clear to me). The focusing motor moves back and forth most of the time before locking on to the subject -- that's what's making it slow -- so I always end up loosing the opportunity shot and have to wait for the subject to return for the shot.

A++++
Shipped on time.
Great Product.
Excellent price.
Will buy from them again and again.

Picture quality are good but make sure to have warranty
I bought this lens in December 2007 and just start to use it from this March. The picture quality is good but needs a lot of light and contrast for the AF to work.
In June, during an outing, one of the element (glass) fell out of it's holding socket and the lens would not retract to below 1:3.
Since I bought this lens in gray market, so that there's no warranty. I just open the lens and fix it myself, works fine.
However, the story did not end there. Just yesterday, during some test shots at home, the lens would not focus and the motor is trying but could not move. I switch to Manual but the focusing ring would not stay at M mode and I can turn the ring freely and it won't adjust the focus (in AF mode, the ring supposed to have resistence from the motor gear and you should not try to adjust manually).
If you are thinking of buying this lens, make sure to buy it with warranty or better yet extended warranty.