when you go into render there is a custom setting and you can alter bits there, remember to give it a new name and save so it is available next time.
I suggest you use MPEG with NO audio and VBR (variable bit rate) and then use the AC3 audio as this will save space on the disk compared to the PCM in the settings supplied.
Highlight about 10 minutes of footage and then render to MPEG , see what size it is and then multiply by 6 to get an an idea of the size for an hours video, this will help in getting your
settings tuned.
Look here I have set up lots of links to Vegas users
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