/Isn't the 70d supposed to be better than the 7d in low light?
It is but only marginally. Full frame is the way to go if that bothers you. I'm sure you've read the specs from both cameras so I won't go into too much detail on that.
Having owned both, what I can tell you, from my experience, is that the 7D is a quite heavy, but very solid bit of kit. It's also the only cropped Canon camera offering a 100% viewfinder. Its a great feature. What you see is what you get.
It's a fast camera too, offering speedy focus and good frames per second shooting. It has many user controllable focus zones, which is great for sport and birds in flight.
The 70D is lighter, of polycarbonate construction, but still quite robust. It has the articulating screen whereas the 7D is fixed.
It has nearly the same amount of focus zones seen on the 7D, and I think the same frames per second shooting.
The 70D has a 20 megapixel sensor compared to the 18 of the 7D. In reality there is not much difference in quality, although in low light images the 70D just edges it.
Where the 70D really excels though is in video. Used with certain STM lenses (18-135 STM and 55-250 STM as examples) it's dual pixel focusing system enables the photographer to take stutter free and SILENT focusing.
That's a feature unheard of in many cameras, even the top end ones.
There are also many customiseable video features in the menus. If you like making videos, then this is your camera!
Given the choice today between the two, then I would go for the 70D. (And I don't normally do video)
There are other differences. Touchscreen, SD v Compactflash but again, its all in reviews easily available for both cameras
They are both excellent cameras though. You'll be happy with whichever you choose.
