Nikon 12 - 24
mm f/4, Tokina 12 - 24 mm f/4, Sigma 10 - 20 mm f/4 - 5.6 and Tamron
11 - 18 mm f/4.5 - 5.6.
Click an image to get it from Adorama. Also try Amazon. It helps me if you get yours at either one.
Focus Specifications (close focus distances are listed under optical specifications)
* Traditional is a motor in your camera driving the lens through a slotted connection on the lens mount. AF-S is a motor in the lens driven by electronics in your camera. Sigma calls their AF-S "HSM"
The Nikon and Tokina are excellent. The Tokina is traditional while the Nikon is AF-S. Both are fast and accurate. it's easy to move the Tokina's ingenious manual focus ring forward or back to change between manual and auto focus.
The Nikon and Sigma are AFS, meaning you may just grab the focus ring at any time and take over manually from AF.
The Sigma is slower than the other two. It's "hypersonic" motor isn't. You can hear a high-pitched whine at about 10 kHz if you listen for it. Worse, the mechanics often make some unsavory squeaks as it focuses that don't engender confidence.
The Tokina and Nikon focus as you'd expect with any AF sensor.
The Sigma and sometimes the Tamron can have serious problem when using any sensor on my D200 other than the very center. Sometimes the Sigma won't lock focus with a side sensor. This means your D200 most likely (depending on your settings) won't shoot! In most modes the D200 needs to confirm focus before releasing the shutter. Often the Sigma won't focus perfectly enough with the side sensors, and will lock up the camera. This makes sense: the Sigma is generally the softest lens of the group. The D200 demands quality optics. If the Sigma can't get sharp enough in the sides to convince the D200 that it's in focus then the D200 won't turn on the green focus confirmation dot on the lower left of the finder and won't release the shutter! Look out for this, since when it first happened to me it confused me for quite a while.
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