Best way to transfer Betacam SP tapes to AVI files?

It first depends on what kinds of outputs your Betacam deck has. I'm going to assume they are all analog and it probably has S-video and maybe component video out. You will need an analog-digital converter like the Canopus ADVC-110 or 300. Connect the analog audio & video outputs of your deck to the analog inputs of the Canopus box. It will convert your Betacam deck's output to DV over Firewire, which Final Cut can capture.

By the way, if you happen to have a miniDV camcorder handy, you may be able to use it as the converter, if it supports analog-digital passthrough (most do). Canon calls this AV->DV out in its camcorder menus.

As for AVI, why do you want AVI files?

+" ... I need to convert these tapes into the best possible, broadcast quality file format ... "+

If you are doing it yourself, DV is about the only way you can go. There are no A-D converters that I know of that save to Apple Intermediate Codec or ProRes (and you would need FCStudio to do ProRes, anyway - are you using FCExpress or FCPro?).

Canopus does have a (more expensive) HD series converters - the ADVC-HD50 runs about $650 and converts analog to HDV, but that in turn would need to be converted to Apple Intermediate Codec in order to use it in FCExpress.



+" ... Everyone (PC heads) has been telling me to go AVI. What would you suggest then? ..."+

Even pc heads should know better than AVI.

But what is your intended purpose? Burn to DVD, provide to a TV broadcast, put on a website, upload to YouTube? That would really determine the 'best format'.

Luke,
If this is for more than just personal use, I think I'd find a video house that has the necessary equipment to convert your Betacam-SP videos to Apple QuickTime ProRes 4:2:2 ... and if you haven't done it already, invest in FCStudio, not FCExpress.