This contemporary variant of the 150 to 600mm lens is great value for money, especially if your new to larger zoom lenses. A lot people question the optics and wrongly turn their noses up at it. Those that do and have used one, have not preprogrammed it with the USB dock. The Sigma dock, is purchased separately to the lens, costing around £30.00. Use the dock and program the lens to your camera and custom settings before using it. Honestly it sharpens the optics aligns the AF and other key aspects of the lens to your own camera. I have some award winning shots from using this lens. Its fantastic value, it’s not a low light or dawn specialist lens, but in decent light, it’s tack sharp and crisp. Any soft images are down to camera operator and failure in the setup. The only down side is this lens is it’s not fully weather sealed. The Sport variant of this lens has full weather sealing, and is a little heavier, plus if sports or wildlife are what you’re after, the sport variant has quicker AF and a slightly larger diameter front element to the contemporary, that makes subject acquisition and tracking a little more efficient. Optically both are just about the same. I still own and use this lens alongside my primes and pro kit, that’s how well regarded this lens. A cracking lens for the money, but get a Sigma USB dock as well, it will be the best £30.00 you spend allowing you a 100% use of your lens, without it you’re only getting around 60 to 70% of the lenses capability.
