50-500mm f4-6 APO EX

I have owned this lens for approx 2 months now as I decided to get it at the same time as the D300S.

Having used a wide range of lenses in the past I am somewhat disappointed in the general image quality of this lens in terms of sharpness and blue fringing at the far end. Also, one major issue with this lens is bleeding/ghosting of white onto the background if the subject is of a high intensity colour (such as a white seagull against a dark background) to the point where I find it unacceptable. Due to this you have to think about all your shots in order to bypass this quite serious issue. My friend also owns a copy of this lens and has the same problems as me.

This issue also exists on my D3 so it seems a be trait of this lens.

The lens itself is fairly light weight making it very easy to achieve successful shots in reasonable light, however due to the other issues of this lens I would not recommend it.

The one very bad thing about this lens is that the paintwork inside the lens tend to flake and collect inside. I had it cleaned once for free by the agent, and now the flakes are slowly collecting again. Otherwise it is a good lens. For sharp pictures one has to be very careful of the lighting conditions ...

I rarely feel strongly enough about a product to post a review, either positive or negative. But I've owned the Sigma 50-500 for almost 2 years now. I've taken more than 1,000 pics with it, and I have more than just an initial impression. It was also my first "big lens" and to be fair, I have taken some really wonderful bird, insect and nature photos with it. But I feel strongly that if you are considering purchasing this lens, there are other more dubious experiences that I want to share with you. About 6 months ago, I could no longer adjust the focal length because the lens extender was jammed. The mechanism that locks the extender had come loose. Naturally, this was not considered a warranty defect and it cost me $150 to fix. Plus, I have a nasty scar along the tube because of the loose mechanism. Ok, so I could live with that, even though I don't feel as though I am "rough" on this lens. It has seen a lot of miles, but it was very protected. However, there are 2 other issues that lead me to believe that Sigma makes inferior products (vs. Nikon or Canon). First, the lens has managed to accumulate a significant amount of dust on the inner lens groups and requires a full overhaul to get at. No telling how much that will cost. I was told this occurs because of the vacuum created when you extend and retract the lens and there is just enough room for dust to get sucked-in. I now have to remove dust from every shot I take with the lens on my D100. And there's one more thing I think you should be aware of. If you envision yourself taking some great action shots of birds in flight with this lens, you need to consider another lens. After hundreds of missed shots and blurred images, I decided to rent a fixed focal length 300mm lens just to see if it was me or the lens. The first 10 shots I took with the rental lens convinced me that the Sigma 50-500mm was simply too slow to capture birds on the wing.

These are simply the opinions and observations of one birder. Your mileage may vary, and if you are ecstatic with your 50-500mm, then I say good on you. That's how I wanted to be when I shelled-out the big bucks for this lens.