You are mis-understanding the feature and/or confusing megapixels with megabytes. As a couple of folks have already pointed out, the number of megapixels does not change.

From my 16 mp Olympus EM10, a jpg using the 2x digital zoom/digital teleconverter is below. You might also be interested to know that the jpgs - regardless of whether I was using the digital zoom or not in that outing - all ranged from just under 6 mb (megabytes, file size) to just over 8.

The raw file is also attached below, hard to see the link hidden between #1 and #3.

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I love Canon and am happy with my little SX700HS. But as a classical-music reviewer, I frequently have to whip out my camera after a performance (never during, for obvious reasons) to take a curtain call or the last seconds sitting at a piano etc. The stage is always fine, the color can be processed with the usual editing. But--depending on my seat--those faces can be blurred. I can't use a tripod, I attempt the "correct" way to hold the camera, the zoom sometimes works, but those blurs from shaking are troubling. I'm ready to buy a new Canon (if not too expensive) with anti-shaking mechanism, but unsure what to purchase. Any ideas?