It's been a good few weeks for DSLRs. Just after Nikon's D90 became the first ever to jump into the sweet, sweet waters of the HD video pool, Canon did a gigantic cannonball today with the EOS 5D Mk II, upping the game to full 1080p captures at 30fps. The question that all of this good news brings up is: Why now? 

 

Sensors: Everything changes when instead of the fraction of a second of exposure for a still image, a sensor has to sustain constant operation to grab a video......

 

Image Quality: When you buy a DSLR, you want everything that comes out of it to be of substantially better quality than what you could get with the compact digital it's likely replacing. That's why the first DSLR movie modes we've seen from the biggies are all touting HD quality—

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