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pix2pixels
06-04-2009, 05:01 PM
I'm just trying to figure this out, playing with numbers...

If the camera records 17Mbs in NTSC (30fps), what is the bit rate for PAL (25fps)?
If it is the same, it means that the implemented compression is ~20% better on the PAL models, resulting in a better picture quality

Please correct me if I am wrong.

squig
06-04-2009, 05:54 PM
you would expect more bits per frame but AVCHD compresses data between frames and has a mind of its own so there may not be much difference but I'm just speculating. it's true 30fps is more data for the codec to deal with but these consumer delivery codecs appear to be designed for efficiency more than quality. My experience withe the variable bit-rate mjpeg on the D90 is that it tries to keep the bit-rate to a minimum and only increases it when it has to. I don't however have any first hand experience with AVCHD other than a bit of pixel peeping. Look at it this way if anything PAL will look better than NTSC and it shouldn't be worse. And there's no pulldown to deal with.