Imagine that you shoot in normal 4×3 mode. Then pretend you take that footage into your computer and simply put black bars on TOP of the image, covering up the top and bottom. Ok, so you have a 16×9 image, but you’ve lost pixels, right? Rather then making the image WIDER you’ve just made it SHORTER. It is 16×9 now, but you’ve lost some of your resolution. Make sense?
Now, when you switch your 2100 to widescreen mode it’s essentially doing that EXACT same thing, except it’s doing it inside the camera. That’s what people mean by “not true 16×9.” It is 16×9, but you’re losing pixels by doing it that way. You’re better off just doing what I described above…just shoot in 4×3 and crop it later. It will all come out the same and you’ll at least have the control later to move the image up and down within the letterbox (somethign you couldn’t do if you shot 16×9 in the camera.)
There are cameras that actually have 16×9 chips (the best) or you can buy an anamorphic lens that squeezes the picture BEFORE it even goes into your camera. The 2100 would use all the pixels on its chip and you’d stretch that image out later. Not as good as a 16×9 chip, but better than using the in-camera crop.
I have the 2000 (same camera, just not as light-sensitive) and it works great. The audio is the only drawback. You’ve only got one mini input. It’s a stereo input, but even IF you run two mics in there (I’ve done it, it works) you have to control BOTH audio channels with the same control. So both your mics better be the same level! But hey, if you’re just using 1 mic it might be fine. Be aware that once you plug it in you’ll be recording ONLY that mic…the camera mic is disabled when something is plugged in.
The PD-170 (or a used PD-150) is the same camera but with XLR inputs. It might be worth a look, at least. But the 2100 is a good camera, no doubt.