Sigma 120-400mm vs 150-500mm Please Help!!

[Moellertime]

I am a relatively advanced photo hobbyist and I currently own a Canon Rebel XSI with the Tamron 18-250mm superzoom that I use as a multi-purpose lens as well as the Canon 50mm f/1.4 prime which I use for taking pictures of friends and family. Recently though I have started to get into wildlife photography and have found that my Tamron is not nearly long enough and that it is unacceptably soft past 200mm. Therefore I am looking for a long, relatively sharp telephoto lens to use for wildlife but would also like to be able to use it for sports such as football. My budget is $1,000 and I can absolutely not spend any more and would prefer to spend less (bigma and Canon's 100-400L are out) and I must have IS/OS/VC as I will often be shooting handheld. I think I have narrowed it down to one of these two lenses given my price range:

Sigma 120-400mm F4.5-5.6 DG APO OS HSM
or
Sigma 150-500mm F5-6.3 APO DG OS HSM

If anyone has another option under $1,000 please let me know

Now given the fact that will often use this lens for wildlife I'm sure you all would suggest the 150-500mm purely for the 500mm focal length which I admit would be nice however for my situation there are several benefits of the 120-400:

Lighter/Smaller: not sure I want to carry a four pound lens around that much and it might be hard to handhold

Faster: Even with OS I still think the faster aperture will come in handy while handholding

Wider: 150mm may be to long for some sports situations especially if I am close to the sidelines although I'm not sure if 120mm will be much better- I can always use my Tamron and just suck up the lower IQ

Cheaper: For most of you it might not matter but for me saving $100 is a good deal

Image sensor: remember I have a APS-C crop sensor so 400mm may be plenty of zoom

Anyone that has either of these lenses or knows a lot about them please give me your opinion of which one would be better for me or an alternative that would serve my purposes

Thank You!

 

[Moellertime]

Please?

 

[Robin Usagani]

Digital Cameras: Digital Photography Review, News, Reviews, Forums, FAQ is always a good site to check reviews on products so you can compare. You can also look at people's review on B&H website on the product.

 

[Flash Harry]

I tried out a 150-500 once and was quite impressed with image quality so either would probably be fine, go for what you need, if its the cheaper lens, so be it. H

 

[KmH]

I have a Sigma 150-500 and find it well worth the price.

You need to know that even with OS, a monopod is almost essential, because weight is a consideration.

Also neither lens has sufficient maximum aperture to shoot at night or in low light. What looks to your eye as a brightly lit football field, isn't sufficiently lit for using f/4.5 to f/6.3 with an APS-C camera sensor. If the football games are day games, you'll be good to go.

The APS-C sensor just isn't big enough to have the kind of high ISO capability needed to get the shutter speed short enough for shooting action sports at the middle apertures both lenses provide.

 

[Derrel]

My impression was that the 120-400mm lens is not that good of a performer...