Originally posted by GaryH The Sigma 50-500mm. Can be hand held but works even better with a monopod. Very good zoom range limits lens changes, very decent IQ for its range albeit a little slow. You should use at F8 or higher for optimum sharpness. Alternatively, the Sigma 150-500mm can be had for $799 and you only lose 100mm at the wide end. Otherwise the IQ is similar. These lenses are made for situations like Yellowstone if you are not willing to spend the $$$$$ that some do for their 5-600mm lenses. Another alternative depending on your pocketbook is the new DFA 150-450 lens that has been announced. It is around $2500 but will offer better IQ and more features than the two Sigmas and it will have WR too. I have owned both Sigmas and have gotten some very decent photo's with them. In fact, I am trying to decide whether to buy another Sigma or wait for the Pentax lens. I have a B&H gift card burning a hole....
Absolutely! I am going to Big Bend next month and the Bigma 50-500 will cover most every need I have. It renders great color, no PF and can be used hand held for 99.9% of what I shoot. It's not tiny, but it is effective and delivers great IQ.
From a landscape at 50mm...
To wildlife at 500mm..
...and everything in between, the Bigma is supreme! If I could only own one lens, it would most definitely be my Bigma!
Regards!