Thought's 50D, 60D, 70D, or other

[telsacoil]

Hi all,
I'm pretty new and want to upgrade within my lenses that I currently have in the Canon line. So I was looking at upgrading from my rebel eos XS to possible a Canon EOS 50D-70D. Right now I can get pretty good deals on the 60D and 70D; and there is one person selling a used 50D with some lenses. I currently live in Alaska and shoot a lot of landscape, aurora, and some sport/portait photos. So I'm kinda wondering what all y'all think?

 

[JohnTrav]

70D since you mentioned sports. You will need the better auto focus system and burst rate of shots.

 

[iolair]

Any of the three cameras will be a significant improvement on the 1000D (XS) in terms of resolution, responsiveness and autofocus.

The 50D has a metal chassis, it's extremely robust; the 60D and 70D have flimsier plastic bodies (though still well built).
The 60D and 70D will shoot video, the 50D won't (unless you use the Magic Eye 'hack').
The 70D has hugely improved autofocus in video and live view.
While there's a 5 megapixel difference across the three, the 33% increase from the 50D to 70D doesn't really matter for real images.
The 70D's autofocus system borrows elements from the 7D's excellent system, giving it a clear advantage over the other two for shooting fast/unpredictably moving objects.
The 70D is slightly better than the 60D in low light, which is slightly better than the 50D. This *might* give you noticeably clearer images when shooting aurora if you use high ISOs (though at ISO 1600 and lower, all three are fine).

If you'll be shooting aurora and landscapes, leave money in your budget for a decent tripod if you don't already have one.

If low-light performance is critical, you might want to see if your budget will stretch to a full frame body, which are a huge leap forward in this regard (eg. the 6D) - but if you have any EF-S lenses, they won't work on the full-frame bodies.

In your position, unless sports and video are really important, I'd go for the 50D or maybe 60D and spend the rest of the money on good glass (and tripod if needed).