Which Sigma Lens??

I have a question for you all. I want to get into doing some wildlife photography and am debating which lens is the best on my limited budget. Right now I have the Sigma 120-400 OS. I have been debating if the 50-500 non OS would be better? I think it is kind of a toss up? Should I stick with what I already have or try and pick up a 50-500? I know they just came out with a 50-500 WITH OS, but I don't have $1600 to spend on a lens right now. Thoughts?

Although I don't have experience with the sigma I would recommend waiting until you have the money for the OS. Plus youprobably should buy a heavier tripod and a gimbel head to help with jitters at 500mm.

Sigma 150-500 has OS. Only about $100 more than the 120-400. I've had both and each has it's good and bads. Obvioulsy the 400 is 5.6 so you can use a non-reporting TC with no affect. The 500 have better reach but no TC, unless you're full frame. Weight is about the same, quality, image-wise and build-wise, about the same. Mine had a slight focus problem that I just couldn't fixed with MA so it's been sent back but I've overall been happy with it.

As an aside, I've also been happy with my Sigma 70-200 and 30. No complaints so far.

If you normally only print A4 or so and upload to a web gallery I'd stick with what you have until you can go for significantly better. The reason to go longer is if you consistently need the length. The 50-500 is a great lens but you will miss OS - swings and roundabouts!

I don't think you will significantly improve on the 120-400 with a $1600 budget.

I have the 150 - 500, cost me just under $900 delivered. The only issue I have with it, is pairing it with another single lens to give me a 2 lens system that covers a full range. The lens itself though is great for me for wildlife/birds and the OS is mandatory for me

I too am happy with the Sigma 150-500 OS, coupled to a 50D. Another 50D with a 70-200 OS and I am set for any wildlife that I happen upon.

Unless you are feeling that the 400mm is not long enough most of the time,. I'd stick with what you have.
If you feel that you need that extra 100mm,. look to the 150-500mm. It is pretty much what you have now, just made 100mm longer.

Just ordered the 150-500OS from Abes of Maine. They take $100 off when it's added to your basket. I got it for under $900.

I'd like to see some images from the 150-500.

For general wildlife shooting you probably can't get much better than what you have. The extra 100mm will make a little bit of difference, but it can be worked around. I am also into shooting wildlife and the longest lens that I have is 400mm and it's even a prime. The 50-500 might have slightly better IQ than the 120-400, but I would take the OS unless you are a frequent tripod/monopod user like me.

J.D.Otto wrote in post #10435025
I'd like to see some images from the 150-500.

These were all taken at 500mm with the Sigma 150-500OS. I am very happy with the lens. It is a little soft wide open. The sweet spot seems to be f/7-f/9 IMO but I am still learning the lens. The AF is quicker than I thought it would be and the OS is better than any other lens I have used. It is a nice lens.