Built in video on those machines will do 320x240 at 15 fps or so and will probably have issues with sound shifting over time. If you want decent captures get a capture card. The PCI PPC models with A/V are not much different then the beige G3's.
If you did get a decent old PCI capture card you would then have to do something about storage drives so you do not lose any frames (built in SCSI is too slow).
Targa 2000's are pretty nice (I have a Targa 1000, 2000, 2000 pro in my collection mostly installed in beige G3's), or a Media 100 might be good (and cheap).
And yes, transfering the files to another system to edit/convert would be a good idea (or just connect the external RAID array directly to the faster machine).
If you did get a decent old PCI capture card you would then have to do something about storage drives so you do not lose any frames (built in SCSI is too slow).
Targa 2000's are pretty nice (I have a Targa 1000, 2000, 2000 pro in my collection mostly installed in beige G3's), or a Media 100 might be good (and cheap).
And yes, transfering the files to another system to edit/convert would be a good idea (or just connect the external RAID array directly to the faster machine).