We all like to think the latest and greatest high-end cameras will save our production or propel us into stardom...or something like that. Cameras are tools, and just because one costs more than another, doesn't mean that the final result will necessarily be all that different. I've used pretty much all of the popular DSLRs out there, and you can get great results from any of them. The question is, once these videos go to YouTube or Vimeo, how much of a difference will there be? Dave Dugdale from Learning DSLR Video asks this very question as he compares the relatively new Canon 5D Mark III to the inexpensive Canon T2i.
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As Dave points out, the biggest difference between the two cameras is ISO performance. This can be a deal-breaker for many people, as they might be shooting in a situation that requires that extra stop or two of ISO performance. Canon's ALL-I codec has been getting mixed results, but the IPB codec in the Mark III should perform better than the codec in the T2i. On paper, the specs of the 5D Mark III run circles around the T2i, but in this real-world example, they aren't very far off, and in many cases, you'd be hard-pressed to tell the difference (apart from high-ISO).
For my shooting, usability is a far more important factor. The 5D handles much nicer and has more buttons that allow for quicker access to functions. I much prefer the ability to change the camera functions by using the top LCD. The HDMI output is also higher resolution on the Mark III than it is on the T2i. Again, these have almost nothing to do with specs -- they have to do with actually using the camera. I prefer a heavier body that fits better in my hands, but for many situations the T2i would work just fine. In the end, they are going to produce a relatively similar result once you apply web compression -- so just because you're "stuck" with the lowly T2i or the new T4i, doesn't mean you can't produce great results if you take care with what you're shooting.
For some people, spending that extra $3000 may not be a smart investment. You can make any camera look great provided that you learn how to shoot and light properly -- both of which take time and practice.
[via Learning DSLR Video]