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I've found FWB Hard Disk Toolkit 4 addresses all the issues all the software RAID programs have which I listed on the digitizing page.

HDT 4.0 allows volumes larger than 4 gigabytes, it will span and stripe across SCSI busses and across drives of unequal sizes, It will also directly create HFS+ volumes instead of having to create an HFS Standard volume then Erase it to HFS+ using the menu.

It also has a good benchmarking utility so you can see the transfer rate of an array or individual drives. Even more important than the transfer rate is reads and writes per second.

If all the drives going into your RAID are the exact same brand and model, format and benchmark one on its own to see how it fares on the data transfer and R/W per second tests. If it falls below 2 megabytes per second or 200 writes per second it'll be a poor drive for capturing at higher rates with Media 100. Test the drive on the internal and the external bus to see where it performs best.

If all the drives going into your RAID are not identical then you'll want to benchmark them all individually to cull the slowest ones. One underperforming drive can drag the whole RAID's performance down. Test the drives on both busses to see where each performs best.

Remember that in a NuBus PowerMac, the external/internal SCSI bus is standard SCSI2 while the internal only bus is Fast SCSI2. Putting a 7200RPM drive on the external bus is going to "throttle" the drive's performance quite a bit, but the write/read per second rate will still be much better than slower spinning drives.

I was surprised to find that the pair of fancy, black, sleek looking IBM 1gig drives I had on the external bus (that were obviously rather expensive when new) could only muster a pathetic 180 writes per second and the write data rate was well below 2 megabytes per second. The only SCSI drive I've benchmarked that was worse was the really old Fujitsu full height 3.5" 500 meg which turned in a "performance" somewhere south of 50 writes per second.

I'd obtained a matched pair of IBM 2gig drives that looked like first cousins to the 1giggers, but they benchmarked with a much faster data read/write rate and well over 200 writes per second. Those are installed inside the Radius 81/110 on the internal only bus.

After finding out how slow the 1gig drives were, I swapped them out for the mismatched Seagate and Maxtor 2gig drives the 2gig IBM's had replaced. The Seagate turned in a performance every good as the IBMs, even on the external bus. The Maxtor's data transfer falls behind and it can't quite hit 200 writes per second but when striped with the other three the aggregate benchmark for the RAID is enough to finally allow capturing at 150K per frame.

The drive I use for sneakernetting exported Quicktime video to my PC is an 18.2gig 7200RPM SCA80 Seagate which I picked up dirt cheap on eBay along with an SCA80 to 50/68 pin adaptor. This drive on its own on the external bus cannot keep up with the Media 100, though that's mostly the "fault" of the Radius' SCSI bus.

Once things settle down and I'm not so busy with things like replacing the engine in a 1984 Chevrolet S-10 2-door, 4x4 Blazer, and after the Fandemonuim convention is over, I plan to get two more of the 7200RPM drives and stripe them together on the internal bus. Their better performance combined with the faster SCSI bus should allow for 150K capture without spanning the RAID across the busses.

Another item I plan to experiment with is poking around inside the Media 100 program file with Res Edit to see if it's possible to increase the capture size upwards from 2 gigabytes since Mac OS 9.1 and HFS+ (and the Quicktime version I have installed) have no problem dealing with much larger files*. Media 100 2.6.2 stops dead on capturing at 2gig, which results in rather short clips at 150K. I suppose it's not so much of a problem if your VCR has full VITC timecode and RS-422 remote control so it can be commanded to reel back to the frame after the last one captured and do another 2gig clip, but it's a pain in the you-know-where to do it manually.

If I can find a way to hack the capture size limit, and they'll work with the program editior, timeline etc, I will of course post on the site how to do it!

*Media 100 2.6.2 will quite happily export Quicktime files well over 2 gigabytes.