External Harddrive

So the "disk-to-buffer" data transfer rate is dependant on the RPM. And the "buffer-to-computer" interface speed is dependant on the type of hard-drive. And with external hard-drives there is also the speed of the wire used to connect the hard-drive to the computer.

So this means that there are many different speeds of MB/S that the data takes as it travels.

Does this sound right?
 
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From what I have been told usb is a serial connection and uses the cpu as part of its control do it can only have data going one way at a time. Firewire is a parallel and runs off its own controller so data can go both ways at the same time. So you get a performance hit both ways with usb. I agree with what has been said about multiple hard drives. Go for a good firewire drive as your main storage and a usb for back up. If you cant share the fw bus with the scanner then scan yo the usb then transfer across. I have noticed there are some rather interesting looking hard drive cradles http://www.amazon.co.uk/NEWlink-eSA...1?ie=UTF8&s=electronics&qid=1244599033&sr=8-1 something like this could be useful as you could use it with 2 hd taking one off site for safety then swap them every wk or what ever. I have no experience with these devices though but I have lost a hard drive twice, the first time it only had music rips on and the second it was a back up drive that got dropped. Drives no matter how highly rated can die back up and back up very frequently.
 
So I have a free Hitachi SATA 3.0 7200RPM hard-drive that my dad got for me. As far as I know, this is a pretty good/fast hard-drive. Looks like the best way to use it with a MacBook Pro is to get a enclosure that supports USB 2.0 and Firewire 800.

Any suggestions?
 
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This is the cheapest 3.5" firewire 800 enclosure on OWC ($70). Is that how much I'm going to have to pay to get the increased speed of firewire 800 with my hard-drive? Seems expensive considering the USB 2.0/Firewire 400 enclosure that go for $25.

http://eshop.macsales.com/item/Other%20World%20Computing/MEP924FW8E2O/

EDIT: Found this after reading more about that enclosure^

"Mechanisms Supported: Any capacity SATA I or SATA II hard drive"

My drive is a SATA 3.0. Will this enclosure not work?
 
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I just talked to an OWC online "Live Support" guy.

Jeremy: Will this enclosure (http://eshop.macsales.com/item/Other World Computing/MEP924FW8E2O/) work with my 3.5" Hitachi SATA 3.0 7200RPM hard-drive?

You are now speaking with Jose Saucedo of Technical Support 7AM-10PM CST.

Jose Saucedo: hello
Jeremy: hi


Jose Saucedo: yep you are right that will work
Jeremy: ok thanks

Jose Saucedo: anything else I can help you with?
Jeremy: no thanks


Jose Saucedo: have a nice day
Your party has left this session.
 
Just want to say thanks for the back-and-forth on this topic. I know Jeremy is the one looking right now, but I'm needing something similar so this has been both timely and informative.
 
I don't know how you guys learned anything before the Internet. It's ridiculous how much I can learn on forums thanks to you guys.
 
This is interesting, I hade a similar problem, o save the big files of my scans (Coolscan 5000) I bought an external hard disk with a Firewire connection to save space on the internal hard disk of my i-mac thinking this was the fastest connection, but I had to learn that if I connect it throu firewire the Nikonscan software does not see the scanner. If I use vuescan it works. No problem if I use the usb connection. What I do now is to scan and save the files (about 110/130 M) on the internal hard disk. Once a week I move them, via Firewire on the esternal hard disk, I bought two of these and switch each other every week. When the files are on both external hard disk I cancel them from the internal one. It seems complicates to write, but with a little discipline it works, as leastit seems me. If anything really wrong should happen I'll loose only last week scans, which having always the original (slides or neg) I can repeat. I should add that I don not scan more than 10-15 images per week.
robert
 
robert blu said:
This is interesting, I hade a similar problem, o save the big files of my scans (Coolscan 5000) I bought an external hard disk with a Firewire connection to save space on the internal hard disk of my i-mac thinking this was the fastest connection, but I had to learn that if I connect it throu firewire the Nikonscan software does not see the scanner. If I use vuescan it works. No problem if I use the usb connection. What I do now is to scan and save the files (about 110/130 M) on the internal hard disk. Once a week I move them, via Firewire on the esternal hard disk, I bought two of these and switch each other every week. When the files are on both external hard disk I cancel them from the internal one. It seems complicates to write, but with a little discipline it works, as leastit seems me. If anything really wrong should happen I'll loose only last week scans, which having always the original (slides or neg) I can repeat. I should add that I don not scan more than 10-15 images per week.
robert
Click to expand...

This is what I'll have to do if I get a Firewire enclosure.
 
According to this chart on the OWC site, firewire 800 isn't 3x the speed of USB 2.0. It's not even double. Are these speeds correct? If they are, then maybe it's now worth it to pay $70 for a firewire 800 enclosure.

Maximum Data Transfer Rate:

eSATA - 1.5 Gbit/s (or 150 MB/sec)
FireWire 800 - 800Mbps (or 100MB/sec)
FireWire 400 - 400Mbps (or 50MB/sec)
USB 2.0 - 480Mbps (or 60MB/sec)
USB 1.1 - 12Mbps (or 1.5MB/sec)
 
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I'm thinking that maybe because I am only moving hi-res scans and not video that the speed difference won't be worth $70.
 
I think it depends on how many scans you plan to move each time. for10-12 files of around 110 MB on my i-mac I did not see a relevant practical difference (but I did not check with a chronometer!)
robert
 
robert blu said:
I think it depends on how many scans you plan to move each time. for10-12 files of around 110 MB on my i-mac I did not see a relevant practical difference (but I did not check with a chronometer!)
robert
Click to expand...

That seems like about the max I would be moving at a time.
 
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