Sigma 300mm f/2.8 APO EX

Very surprised by the quality of workmanship put into the lens. Autofocus works fast and accurate. Used with Sigma 2x tele, showed no weakness of edges or vignetting. Lens hood very well built and easy to attach. Use for wildlife photography in Alaska, and is built rugged enough for back country hiking.

Solid build, fast autofocus, works great with 2x teleconvertor

none that i have found

Canon ef 300mm 5.6 Sigma 50-500mm 4.0-6.3 Canon fd 500mm 4.5 Canon fd 300mm 4.5

The paper I worked for recently got one of these as a backup 300/2.8, and I''ve been pleasantly surprised with the quality of this lens. Being a third-party lens, I expected the worst, but I would be hard-pressed to find a difference between this lens and our Nikon 300 in a side-by-side comparison. It''s just as bright, sharp and contrasty as the Nikon, and autofocuses nearly as fast. I''ve taken it to a few basketball games this winter, and every time it''s performed well for me. After some bad experiences a few years ago, I''d given third-party lenses a wide berth, but this one''s clearly a solid performer.

Fast AF, light compared to many other 300/2.8s, very good quality optically

Lens hood falls off at the drop of a hat.

various manual and autofocus 300/2.8s and 400/2.8s by Canon and Nikon, a really crummy Tokina 300/2.8 MF

After becoming frustrated with the limitations of my old 400/5.6 I decided to spend the money to get a fast telephoto. A 300/2.8 seemed a good compromise as far as size/weight/cost were concerned and I thought that a high quality teleconverter would allow access to longer focal lengths and give me a little more versatility for my money. For Pentax autofocus my choices were limited to Pentax and Sigma and, as much as I'd love to get the Pentax FA-300/2.8, my budget limited me to the Sigma. (Well truthfully, my budget limited me to not getting either but I decided I deserved a birthday present!)

Construction, fit and finish are superb. This feels and looks like a very well made lens. It comes in its own rectangular, well-padded soft case. They even include a 46mm circular polarizer (this lens uses drop-in filters so you don't have to buy huge filters to screw onto the front of the lens).

Autofocus is fast with a minimum of hunting (this is an f2.8 after all) and, much to my surprise, manual focusing is excellent as well.

Image quality is gorgeous, even wide open. I've been able to get some dazzling shots with this lens. Sharp and contrasty with no light fall-off in the corners at 2.8. Very nice bokeh, which is a really pleasant surprise; the out-of-focus areas can be a significant portion of an image with a long lens like this, especially at wide apertures, and the Sigma renders them very nicely indeed. I'm finding myself shooting wide open or at f4 quite a bit because of this. The shallow depth of field can be really fun to work with.

This lens is big and heavy, so a tripod or monopod is essential for just about everything. The built-in rotating tripod mount works very well.

I purchased Sigma's EX 2x APO teleconverter for this lens and have also used my Pentax 1.7x TC with it. Both work beautifully with little loss of image quality and no vignetting or other obvious artifacts. Using the Sigma 2x makes manual focusing a bit balky, due to the stacking of mechanical linkages, but not enough to complain about given the image quality and the sudden affordability and convenience of having a good 600/2.8 available! I have an inexpensive Sigma 1.4x TC as well but have only taken a couple of shots with it; enough to tell that there's no problem with vigneting or anything else drastic, but not enough to seriously evaluate image quality. I'll probably stick with my Pentax 1.7x and the Sigma 2x for the most part.

Complaints? The biggest one I have is that the supplied lens hood won't fit on the lens backwards for storage when I have a Bogen hexagonal tripod plate attached. A little work with a hacksaw (on the tripod plate, of course!) should take care of that but I'd rather I didn't have to. I'd also like to have a front filter thread in order to attach a UV filter for protection. The lens does have a built-in multicoated plain glass element for protection in front of the front lens element, and replacing that would be infinitely cheaper than replacing a damaged front lens element. But it would still require me to send the lens in for repair rather than just screwing in a new filter myself and I wouldn't want to part with this lens for that long - it's too good.

Superb image quality. Fast. Versatile.

Big and heavy (like all 300/2.8 telephotos)

Sigma 400/5.6 AF

None needed yet

Sigma should back their lenses with a longer warrenty.

Good quality and well build. No need to fiddle with switches in order to change from manual to AF. Great optical quality. fast and silent AF, even with converters.

tripod collar is sticky to rotate. vignetting when used with converters.

Nikon, Sigma and Tokina

Effective but slow in NZ