I own a sony pd 170 and am very happy with it, however, I know that HD is the way to go. Trying to find an HD camera that allows me to shoot HD/SD as well as 16X9 & 4X3. The biggest thing for me is a camera that allows me to shoot in low light without any noise in the footage. I don't like to stand too close to the subjects and I normally use no more than 10-20 watts on my light. Any suggestions?
There are a few cameras that still shoot both SD and HD. The Canon HV20/30/40 does, but none of those models are terrific in low light. You have to go to a more expensive camera for good low-light handling. Here are a couple of cameras that still shoot both SD and HDV (on tape) and are reported to be very good in low light:
--Sony HDR-FX1000, $3,199
--Sony HVR-Z5u, $4,250 -- the prosumer version of the above, with XLR audio inputs
There is also the Canon XH-A1s ($3,400) which is also tape-based and shoots both SD and HDV. I am not certain about its low-light capabilities. It seems to be the successor to the great SD Canon, DVX-100b, which worked well in low light. If you go to B&H's description/reviews, wedding videographers seems to like it -- which strongly suggests it works well in low light.
Otherwise, you could shoot on one of the new Panasonics, or as already suggested the Sony EX1 or 3, and downconvert to SD when needed.