Evaluation: 
Conclusion: Wonderful Lens
Review: I'm a professional photographer[...] and until now, have never owned anything but Canon or Nikon lenses. For years I specialized in sports photography and the lenses I most often used were a 400 f:2.8 and a 600 f:4. I moved on to other fields of specialty and decided I didn't want to lug around that kind of weight and got rid of the big glass. Now, several years later, I decided I needed a long lens again, but in a decidedly smaller package. After trying an unnamed top manufacturer's 80~400 lens and being unhappy with the quality of the image, I dared to try Sigma's new 120~400. I ran the lens through the ringer and tested it under every situation I could think of and through it all, it has performed flawlessly! In fact, I was ready to accept a little less sharpness, so when I evaluated my results, I was thrilled. I highly recommend this lens and I have the utmost confidence in this beautiful package of glass.
Evaluation:
Conclusion: Great lens
Review: I am very happy with the purchase of this Sigma. Before, I also purchased the Macro 105 mm (also from Sigma) and the great quality of pictures that my wife are getting (mostly of insects) convince me to repeat the business with AMAZON. This 400 mm, a bit heavy to use without tripod at the beginning, became rapidly a wonderful tool once you get use to it. We are mostly fascinated with the fast AF it has, and could easily occurred that, instead of getting a nice sparrow hawk flying, you get a very sharp tree suddenly interposed between your camera and the bird at the time you was shooting. In any case it gave us lots of fun. We, as ornithologists, recommend this product to anybody without any negative observation.
Evaluation: 
Conclusion: Another Sigma with calibration issues
Review: I bought this lens after returning a 150-500 for back and front focusing issues on a Nikon D700. Well, the 120-400 suffered from the same problems. My copy had bad back focus at 400mm. Using the D700's AF Tune function I could compensate to get it to focus correctly at 400mm, but that introduced severe front focus issues from 120-250mm. Overall, I could get the 150-300mm range to focus well if I gave up on the 120mm and 400mm ends.
As with the 150-500 order, Amazon's shipping department did a totally inadequate job of padding the shipping box. There wasn't enough airbags in the box to prevent the Sigma box from sliding around let alone protect it on all sides. In all, my two Sigma lens orders received the same level of packaging attention as the book and DVD orders I've received over the years. This is a very bad situation for anyone interested in purchase precision optics from Amazon.
Evaluation:
Conclusion: Use a tripod.
Review: This is one big hunk o' lens (5 lbs) that benefits greatly from the use of a sturdy tripod and a remote shuter release. The photos I took were acceptably sharp on a tripod, but it takes a steady hand, even with the OS, to get similar results hand-held. I'm not yet convinced that the OS, especially at the 400mm setting, actually gives you a 3-4 shutter speed advantage. Maybe this will improve as my technique improves. I was also suprised to read in the isntruction sheet that you must wait approximately 1 second after pressing the shutter release half-way to get a stable image. Is this common to all image-stabilization lenses? I was also somewhat confused by the OS instructions which call for OS 1 for camera shake, and OS 2 for subject travel accross the horizontal plane. Since the instructions also warn against using OS while the camera is on a tripod, this seems inconsistent with the stated use of OS 2. The HSM autofocus is very quiet, but sometimes has difficulty locking in on the subject. This is probably not much different from similar lenses of this type (I've read identical complaints about the Nikon lens). However; the all-the-time manual focus over-ride comes in very handy in those cases where the auto focus system is having a hard time. Having had the lens for just a few days I think that, for the money, it will fill my occasional need for a long telephoto lens.
|
