Physical differences are more obvious between the cameras, with the EOS 70D possessing a smaller body than the 7D Mark II, and offering a hinged, 3in LCD screen rather than a fixed, 3in LCD screen. The hinged screen on the 70D could be of benefit to those of you who regularly shoot from peculiar angles. The fixed screen of the EOS 7D gives it a slight advantage in the thickness stakes, but it's negligible. Mainly, if you're already used to shooting with the screen at an angle, then you will find the 7D Mark II limiting.
Button layout and control is a little different on both models, with the 7D offering a more comfortable user experience. It has a separate stick for navigating the menu system, whereas the menu navigation on the 70D is done by pressing a multi-directional pad that sits inside the rear control ring. The lack of a hinge on the 7D Mark II allows for more playback controls to be placed on the camera body, so you can do things like bring up an in-camera edit menu.
Which of these cameras should you do for? If you're strictly into action photography, then the 7D Mark II is definitely the one to choose, mainly because it's so fast (10 frames per second). It's also well suited to capturing Full HD video (at up to 60 frames per second), and it's better rated at working low light (up to ISO 16000 compared to 12800 for the 70D). Retail pricing was $2200 for the body only at the time of writing.
The 70D cost $1250 at the time of writing, and is still plenty of camera for the price. It's quite fast at seven frames per second, and you get the added benefit of the hinged screen. Indeed, if speed and also versatility in terms of the angles you shoot are important to you, then the 70D is the one to choose. It's also the safer option for your finances, and gives you a bit more to spend on lenses.
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