Expert: LizaL - 2/23/2005

Question
Hi, my question is I had to reinstall my Photoshop after getting a new hard drive and In the beginning the program told me I should put part of the program on a seperate drive to make the program run better.  But I don't know how to create a new drive or which part it was telling me to move.  Do you have any idea?  the version in Photoshop 7.

Answer
Hi Nanci,

What's being referred to here is a scratch disk. And what this basically means is that Photoshop needs a place on your hard drive where it can write temporary information as it processes your work. In other words, let's say you have a Photoshop file open. As you work on it, making changes and additions to it, Photoshop uses parts of your hard drive for writing temporary files as it processes. You don't see this happening; you can kind of think of it as a background process. And the place where Photoshop writes this information is called your "scratch disk."

A scratch disk is sort of like virtual memory. It's recommended that you use a separate hard drive, or a partition of your regular hard drive for the scratch disk. And if you have your hard drive partitioned, it's preferable to use the largest partition for your scratch disk.

Now you say you just installed your new hard drive -- well, maybe I've caught you in time, before you've put all your applications and information back on it, because if you want to create a good scratch disk, you'll go back and reformat your hard drive, and partition it. Then you can assign one of the partitions as your scratch disk.

But if it's too late for that, you can just assign your entire hard drive as your scratch disk. Depending on the size and complexity of the files you work on, this might be just fine. But if you have a need to work on really big images that require a lot of complex editing, it may be worth it to you to go back and partition.

All this talk about assigning a scratch disk, and no advice  as to how to do it! So here's how:

1. Go to your Photoshop pulldown menu and select Preferences.

2. Select Plug-Ins and Scratch Disks from the submenu. Then you'll see a dialog box where you can navigate to the  disk you want to assign as your primary scratch disk, and also assign other scratch disks too, should the primary get slowed down.

Here's a visual:
http://little-works.com/all_experts/scratch.mov

You can see here that I've assigned my scratch disk as my largest partition, and then I've assigned two other scratch disks -- and these are other partitions of my hard drive, as well.


As I said, it might not be a real necessity for you to even assign a scratch disk. It does make Photoshop run better, especially if you have large images to process, but I guess you need to decide if you're willing to reformat and then partition your hard drive in order to do it in the recommended fashion.

Hope this helps! Please post back if you need me to clarify anything. I'll be busy with a couple of deadlines for the next few days, but you can email me at lizal@little-works.com.


Lisa