sigma 28-300

anyone have anything to say about this lens?

I have the Sigma 28-300mm f/3.5-6.3 Macro (not the new DG model). It has a red ring though!

Don't pay too much for it. It is a compact lens which is good. 62mm filters aren't too expensive. The zoom lock is a nice feature although mine doesn't creep anyway. Focus isn't super fast but not bad although a bit noisy. Sigma includes a hood (use it). Focusing is all internal. The front element doesn't rotate or extend on focusing. You only get the 300mm field of view at infinity though. As you focus closer, you lose focal length. 1:3 magnification is pretty good and it focuses pretty close.

The lens is a bit delicate. Be careful not to hit the front element against anything or the little supports inside can break and leave it loose. I bought mine used and didn't realize that it was this way. Luckily I didn't pay too much for it. A local repair shop was able to fix it and recalibrate and align the lens.

The focus ring feels cheap. The zoom ring is a bit stiff and the force is uneven as it rotates.

It's not the sharpest lens around especially at 300mm. It is much better on full frame where you magnify the image less for the same output size. The aperture is quite small at 300mm. The f/6.3 seems to be optimistic. It meters with slower shutter speeds than other 300mm lenses at the same f-stop although it exposes a bit brighter too. You'll get used to it. Stopping down improves the sharpness. Chromatic aberration,distortions and vignetting can be easily fixed after to improve the image quality.

The lens is useful for shooting parades on sunny days with the 5D. You can zoom wide and get a whole float, then quickly zoom in close on one persons face. It works good in P-mode so that the camera chooses faster shutter speeds automatically as you zoom in. Set the ISO high enough so that it usually is stopping down a stop or so.

I guess that I'm saying that if you use it with a good camera and stop it down some, that it is an ok lens for informal situations where you convenience and small size are the dominant goals and you can work around its limitations.