Hi Nick,
This is the best way to do this.
1. The video MUST be output and captured into your computer via SDI as uncompressed 10-bit video.
2. So, if you have anything between the tape deck and your computer that is not SDI, abandon it, make it disappear, give it away to the Salvation Army…
3. Capturing the video via SDI has two great advantages:
a) the color will be an exact copy of what’s on tape.
b) the audio levels will be an exact copy of what’s on tape.
Digital Betacam players have knobs that allow you to increase or lower the saturation, lift or lower the pedestal and lift or lower the luma level. It is possible to set the knobs to their default settings, which would allow you to capture an exact copy of what’s on tape.
My suggestion is that you also use a waveform monitor and vectorscope connected to the player when you capture video. This is a great way to make sure all is well while you capture.
-Paul