Neighbor let me borrow a f2.8 sigma 70-200mm lens and IT really was a joy to use. plus a picture of my dad and my dog for the record books. it catches great detail, like the slobber that goes flying out of my dogs mouth when he runs full speed.
Do not let a german sheperd or doberman mutt slam into you at full speed. It is not pretty. IT hurts, and it will put you on the floor at least.
Fetching tip in case you are a dog lover and did not know the secrete of fetch. IF you play fetch with your dog, take 2-7 balls with you. The dog never wants the ball he has, he wants the ball you have. Throw the second ball, and He will drop the first one and go taking off after the second one. Rinse and repeat. Except to lose balls when playing fetch. Its a part of the game.