Re: 16-235 vs 0-255?

You are looking at difference color spaces...

Y'CbCr - this is what's sent over SDI and recorded onto digital formats like dBeta. Legal black level is always at 16(Y'), and white level at 235(Y'). Note that the unit there is Y'.
Sometimes mistakenly called YUV. If it's digital, they are probably referring to Y'CbCr.

R'G'B' - lots of computer-oriented programs use this. Legal range is usually 0-255(RGB), but is sometimes 16-235(RGB). This behaviour depends on what codec you are using to convert from RGB<-->Y'CbCr. Some codecs want to see 16-235 levels, most want to see 0-255.

Y'UV - when the signal gets converted into an analog composite signal, the luma and chroma signals are modulated together. The resulting composite signal has limits on its levels... usually no higher than 115~120IRE and no lower than -20IRE. Some broadcasters set the limit (for max composite IRE) lower.
For luma alone, it should usually be from 0-100 IRE (for PAL).
One an analog hardware waveform monitor, toggling the 'LPASS' or low pass filter will show you either the luma, or the composite signal.

Pay attention to the units!

2- When it comes to composite signals, there are limits to extremely saturated + bright colors. A 255 0 0 RGB red can be illegal (even assuming your Y'CbCr/video codec wants to see 0-255 RGB levels).