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No, you're misinterpreting. For £500, you can get a basic HD camera, but for £300 - £500, you can get a great SD camera. The quality of the SD camera will beat the HD one hands down, not to mention there's little point in having HD footage in the first place when SD is more than practical for current usage (judging from responses!). Future proofing is why you get a MacBook, the MacBook edits it fine, but really, to go into it seriously you'll be wanting a Mac Pro, unless you get into it in a few years, by which time MacBooks will be even more powerful and more capable.