Photoshop CS3 Essential Preference Settings

Photoshop CS3 Essential Preferences: Performance

Click on the Performance category on the left to bring up the new "Performance" options:

As you can probably tell from the name, this one has a lot to do with how well Photoshop performs. The "Performance" category in Photoshop CS3 is really a combination of the "Memory & Image Cache" and "Plug-Ins & Scratch Disks" categories from previous versions of Photoshop. It also now contains the "History States" option which used to be located in the "General" Preferences. Let's take a look at each section separately, since they're all important.

Performance Preferences: Memory Usage

The "Memory Usage" section is where we can set how much of our system memory Photoshop is allowed to use:

In Photoshop CS3 we can see an "Ideal Range" listed, which is the amount of memory that Adobe recommends we assign to Photoshop based on the amount of available system memory we have. Photoshop automatically assigns an amount for itself based on that ideal range. As we can see in the screenshot above, it's giving itself 71% of my available memory. You can drag the slider bar left or right to increase or decrease the amount of memory available to Photoshop.

It may be tempting to slide the bar all the way to the right and hand over all your system memory to Photoshop, but that's not a good idea. Keep in mind that there's other programs running on your computer as well which all require system memory. I'd recommend leaving this option alone. Chances are, you won't notice any huge performance benefits by giving more memory to Photoshop, since you can never have enough system memory with Photoshop anyway. You're more likely to notice your computer running slower because you've assigned Photoshop too much memory.

Performance Preferences: Scratch Disks

Below the "Memory Usage" section, we find the all-important Scratch Disks option:

If there's one option in all of Photoshop's Preferences that has the biggest impact on performance, it's this one. I mentioned a moment ago that you can never have enough system memory with Photoshop. It will always need more memory than what you have. So what does Photoshop do when it runs out of system memory? It turns to the "scratch disk".

What's a scratch disk? It's an area on your computer's hard drive that Photoshop uses as memory. Unfortunately, hard drives are nowhere near as fast as system memory is, so you'll definitely notice a performance decrease whenever Photoshop has to use the scratch disk. There's no way around this, though. Such is life with Photoshop. However, decreased performance is better than the alternative, which is no performance. If Photoshop runs out of both system memory and scratch disk space, you'll get an error message telling you that it can't do what you've asked because your scratch disk isn't large enough. To make sure you never run into this problem, it's highly recommended that you buy yourself a second hard drive and then assign that new drive as Photoshop's scratch disk, which you would do here in the Scratch Disk options. I have a separate drive, "E", which I'm using as my scratch disk. By default, Photoshop uses your "Start Up" drive, which is usually "C", as the scratch disk, and that's not what you want at all, since it will be constantly competing with your operating system for drive space. You can partition the drive and then assign one of the partitions as your scratch disk, but even that isn't ideal. Your best bet for maximizing Photoshop's performance is to have a second hard drive installed in your computer and assign it as your scratch disk.

Performance Preferences: History States

Over in the top right corner of the Performance options, you'll find the History States option:

This option determines how many undo's you get when working in Photoshop, which you can see in the "History" palette. I usually set mine to 50, which allows me to step back through my last 50 steps. You can set it up to a maximum of 1000 if you like, but you'll most likely run into performance problems if you do. I'd recommend setting your History States to somewhere between 25-50 depending on how much system memory you have. If you find you need more and you haven't noticed any performance problems, you can always come back here and increase it. Likewise, if you're noticing some performance problems, you can come back and try a lower amount. You'll need to close out of Photoshop and relaunch it for the changes to be applied.

That takes care of our look at the essential options in the Performance Preferences. There's only a couple more options we need to look at, and the first one is in the Cursors category, which is where we're headed next.