Photoshop scratch disk for a laptop

[roamingstudio]

Im looking at many various options for a system to use for

photo-processing : either I purchase new kit, or I reuse my Dell D600

laptop. Most processing will be for white balance colour correction;

and stitching together landscapes : either to wide angle or to

increase dynamic range (ie combining foreground + background

exposures etc).

 

One of the key things ive noted is the need to have as much ram as

possible - and when PS-CS2 runs out, it will use its 'scratch disk'.

If I buy a new machine then no problems as I would spec it with 3

hard disks (1xOS, 1xPS-CS2 scratch, 1xdata + images). However the

significantly cheaper option is to use my existing laptop (which has

sufficient ram + video etc) with the downside of only a single hard

disk. A networked remote hard disk server

(running embeddded linux + samba server + gb ethernet) is sufficient

for image storage / retrieval - which leaves open the question of the

photoshop scratch disk...

 

What is the best way of adding a scratch disk to the laptop? Are

memory sticks sufficient? Are external hard drives (USB2.0 through

small hub) going to be ok, or will the slowness kill my apps? What

about gigabit ethernet connections?

 

Obviously if I can reuse my existing machine it means I would have

more money for a decent external monitor (e.g. Dell 2405FPW) which can

be properly colour calibrated.

 

Any ideas / thoughts?

 

Thanks, Marc

[peter_berger1]

My only-somewhat-flippant answer is "buy a Mac." But I realize that's unfair, given the cost

outlay. More directly, the better solution is "don't run out of RAM in the first place." If

you're swapping to the disk you've already lost; the win you'll get from having a dedicated

scratch disk is minimal compared to having enough solid state RAM. If you can add more

RAM to your laptop, do that. I'd say don't bother with the scratch disk route at all.

[moli_luo]

I was in your shoes a few months ago and what I did was get a 160gb WD EIDE HD that they sell for ridiculously low prices nowadays (now that SATA is here to stay) and then you can buy a USB 2.0 HD enclosure thingy for like $20 and that works like a charm. Not only can you put the HD aside and replace with new one if it fills up, it makes things much faster, too, although certainly not as fast as having it internally mounted and connected through EIDE but it does the trick since that removes your slooooow laptop HD revving like crazy from the whole process. Plus 7200RPM desktop HDs are much much faster than any 2.5" laptop HDs - really not only with PS but with games or doing anything in general. Ultimately, what I did was get a Dell 4700 desktop for around $450 (with 17" LCD w/ DVI connector) and spend about $200 and upgrade RAM and HD so it Photoshops like a dream now (2x160gb+40gb hds, 1.5gb RAM), so if you're looking into that route, that's something to think about...

 

Good luck!

[akajohndoe]

I use an external USB disk drive - 160GB.

[Ed_Ingold]

A network drive is way too slow to serve as a scratch, or even working disk. Try transfering images over a network some time, or burning a CD.

 

The scratch disk on a laptop should be an internal disk, which is much faster than an USB or Firewire external drive. It's OK to use an external drive as the working disk - even preferable (because you can swap out different projects, and easily swap projects between computers). Either USB or FireWire will work for you.

 

I occasionally use a network drove as the working drive for onesies and twosies. It takes a lot longer to download and save images, but it's faster than swapping drives or burning a CD/DVD. Once you have it loaded, there's no slowdown if the local drive is the scratch drive.

[moli_luo]

One thing to keep in mind though is that laptops with two internal hard disks are hard to come by - for laptops with only one internal HD, setting your scratch disk on the same volume as your program file and your pagefile and your photos will severely slow everything down. From experience, while internal laptop HDs theoretically transfer data faster than USB 2.0, the bottleneck I noticed is not from the interface bandwidth but from the speed of the disks. Probably because my aging laptop has a 4200 (4300?) rpm HD but having an external 7200 USB2.0 HD speeds up everything - before it was infuriating sitting there hearing the laptop HD crunch away.

[sean de merchant httpw]

USB is a bad call as its average performance is rather low. Going through a USB hub and being shared with potentially slower USB 1.0 or USB 1.1 devices will make it insanely slow.

 

Firewire 400 (IEEE 1394a) will work. While Firewire has a lower peak bandwidth, it has a much higher sustained bandwidth than USB 2.0 it will give you roughly 80% of the performance of a fast 7200 RPM 3.5" hard drive. A 7200 RPM 3.5" hard drive accessed over Firewire may exceed the performance of a low power 5200 RPM 2.5" notebook hard drive. Please note these numbers are based on benchmarks and various configuration issues (chipset, drivers, ...) will cause your mileage to vary somewhat (could be better, could be worse).

 

But having enough RAM in the first place is the most important thing.

 

some thoughts,

 

Sean

[Ed_Ingold]

USB1 is slow, sure, but USB2 is nearly as fast as FireWire. I use USB2 for streaming AVI video. The camera is FireWire and the disk is an external USB2 (IDE) drive, often attached to a laptop (1.4GHz Centrino).

[coconutdaydream]

i have 3 two gig partitions<br>

plus 768md of ddr<br>

works like a champ for me

[sean de merchant httpw]

Correct me if I am wrong, but the last I heard USB 2.0 dropped to USB 1.0/1.1 speed whenever there was a slower device used. Hence, a USB mouse could theoretically make your hard drive slower. I have never heard any claims that sustained USB 2.0 performance exceeded that of Firewire (400/IEEE 1394a). And with PS scratch disk usage it is sustained read and write performance that matters (as you are moving a lot of data).

 

As for multiple partitions on a single drive, why? Doing this will increase your seek times (from one partition to another) and decrease overall performance.

 

some thoughts,

 

Sean

[roamingstudio]

Thanks for all the input - it sort of helped clear my mind a little.

 

Yes I would love to go the iMac route - but I grew up on Windoze - and dont want to change everything just yet (especially if they go the route of mactel - but this is a different thread....).

 

Unfortunately im stuck with only 2xUSB2.0 - and believe the hub issue would be a problem if I plug in slower devices... I will just need to make sure I dont! (ie hub my mouse + tablet). It would make a nice elegant solution - at least for now. Using an gigabit ethernet for the data server is fine - interal for os, and external usb for scratch.

 

So in the meantime I will start looking for a nice monitor... with external hard-disk - and maybe in a year or two when 64 bit has become standard, or mactel is defacto, then upgrade again.

 

Thanks,

 

Marc

[Ed_Ingold]

USB2 is backwards compatible with USB1 devices. However, each device is separate. Using an USB1 mouse will not affect the performance of an USB2 external drive.

 

There is not enough difference between the speed of FireWire and USB2 to write home about. I use an USB2 drive every day to capture AVI video, which streams at over 3 Mb/sec, and get zero dropouts. (Video capture has zero-tolerance for drive hickups.) Still, the internal drive interface is about 3x as fast. An external drive is fast enough for audio/video capture or to upload/download files, but would not work as well as the internal drive for the scratch files.

[roamingstudio]

Someone mentioned to 'go mac'... which got me to thinking. Does the mac suffer the same problems with caching / memory etc? What sort of spec is needed on the mac - the same as a PC or is the architecture so much different?

<p>

<i>

Thanks</i>