I gave a lot of thought to purchasing this lens to photograph birds. I've yet to get the beautiful kind of shots I expected from it. Mostly it is quite difficult to get in a position to use the lens to its best advantage and full capacity.

Excellent optically and gives unparalleled reach and ability to frame shots. Heavy and demands care in handling. Before purchase I tried 600mm f4 and could detect little difference in quality. The flexibility of the zoom made the decision on purchase easy.

• +

  Extreme reach, Sharp, Brilliant rotating filter system

• -

  Heavy (but this is unavoidable) Finish is good but not great. Attracts lots of attention. Case provided is OK for storage but not for carrying. I have a Lowepro Super Trekker which will carry this and a range of other kit.

Great lens in my book. Despite of the weight, this lens is great for birding. I managed to get great photos of bulbuls, sunbirds, and other tropical birds which was probably 150 yards away from me. Tripod is a must I'm afraid.

Hope over experience when I bought this one but I confess to being obsessed with focal length. You can see things you'd never normally see with a big lens. This 'sigmonster' is about the same size a Nikkor 500mm and about the same weight. You can easily hand hold it.

Easy to use, Quick, silent focussing with almost no hesitation on my Nikon DSLR's Shows virtually no vibration. Can be used wide-open at f5.6. Can be propped on the car widow frame for quick wildlife shots. Good finish.

• +

  Natural colors, sharp images that can be blown up to see excellent captured details., Very quick focussing that can be tweeked or over-ridden manually., A joy to use and fairly easy to carry, either by the supplied strap or by its handle.

• -

  The case is made of stout canvas and protects the lens well. However the zippers along each side could be heavier.

I own this lens a little over a year and I am very pleased with the results. I hesitated between the Nikon 500 and this lens. The Nikon had more contrast and sharpness and a more bluish character. I use it for birdphotography. I like it’s versatility. The ability to zoom gives you a high hitrate.

• +

  Color, Zoom, contrast, sharpness. Excellent to 700mm very good @ 800mm

• -

  Yes it is heavy!, The finish of the lens. Use lense Coat!

A great lens in the super telephoto range. Sharp at the full range. Good contrast and color. When used with my Canon Mark II AF is right on and reasonably fast for such a range. Also, if you use the cheapo (not SP)Tamron 1.4x or 2x extenders, full autofocus is maintained.

• +

  AF, Range, Sharpness, Price

• -

  Size, weight, no IS