Ultimately, this [the EOS 70D] is still the best all-around DSLR in this price segment, pending our test of the Pentax K-3. The video quality is top notch, the still image quality only suffers in extreme low light, and Dual Pixel AF offers a usability advantage that nobody else can match. For a consumer-level shooter or hobbyist that wants a durable, control-laden DSLR that can do video and stills equally well, the 70D is the choice to beat. That said, the 70D still feels like a bit of a missed opportunity; had Canon simply matched their competition and included a headphone jack and a second card slot, this would be a slam dunk selection across the board. As it stands it’s still an impressive update that improves on the 60D in many ways, but there’s certainly room for future improvement.
About the Dual Pixel AF they write:
Dual Pixel AF is a massive upgrade over previous DSLR video efforts. In the DSLR video revolution, this is the storming of the Bastille. Even cameras that offer integrated phase-detect on sensors aren’t this smooth, as they only draw from maybe 100 points at most. For the 70D, having the entire sensor feeding autofocus information results in simple, accurate AF with none of the hitches that have tripped up previous DSLRs
If you are interested in knowing more, there is an interview with the engineers behind the EOS 70D and its revolutionary AF system.
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