Scratch disk??

In photoshop, I was trying to use an action and got the message that the scratch disks were full. What is a scratch disk and what do I do to make it "unfull" lol. Thanks!~

The scratch disk is where photoshop stores the temporary files for the images that you're working on, and it can become quite large since it's also storing all the undos. If your scratch disk is full then PS can't complete operations like running filters because it doesn't have anyplace to write the new temporary file. It's best to set your primary scratch disk to a different physical disk than your operating system is on. You can set it to C: but that will cause it to perform operations slower.

Mine said that, but I guess it was because my hard drive only had 100MB free space before I started Photoshop. I needed to clear off some programs and now there's plenty of room.

Why is it called scratch disks? Sounds aweful.

Because all the images it saves are temporary, scratch pictures, sketches etc. It's another of those fun quirks that goes back to photography days I think, when you'd experiment with different printing methods and scratch them so you didn't sell them by accident. At least that's what I was told when I asked and it seems plausible.

I think it goes back farther than that, to the days of pencil and paper. Maybe to the days of charcoal on cave walls.

When you draw stuff, if you're experimenting, you always have to make a copy that you don't intend to keep to see if the technique works. When you're learning you always have to make practice copies. These have been called "scratch" copies forever.

I think that's where the phrase "making something from scratch" comes from; building things from the scratch copies on up. But I'm not sure.

But yeah, the "scratch" disks are just your startup disk, and then whatever disks you have designated as scratch disks, in the order you designate them.

In the newer versions of PS, you can always Purge the temp files if the scratch disks get full. It will mean that you can't undo, use any of the History tools, or keep whatever is on your clipboard, depending on how much you purge. But you can find the command under the Edit menu. (And it's faster than quitting PS, deleting things from your drive, and restarting. )

Hope this helps!

To remedy the problem make sure your not working on an excessively big texture, reduce the amount of undos in the preferences, and as others said, make sure there is enough room for the scratch disk.

lol I forgot to check back for answers lol. What's funny though is everything else works, all my filters, plug-ins, and even the other actions I have. Just that one gives me a message. And i have 1.6 gb free on my hard drive. Thanks for all the answers, it's probably not something I'd really need to use anyway.

I am also haveing memory problems in Photoshop.
Of course I have found I like working on huge files, but I have a gig of Ram and 250 gigs of hard drive.
the choices I see for a Scratch Disk is "Startup", "C:\" and " D:\... However D: drive is a virtual drive on the main hard drive and only has 4 Gigs which 2.38 gigs are used already for Boot sector ( I believe).
I assume "Startup" and my "C:\ drive are the same.

When you say "It's best to set your primary scratch disk to a different physical disk than your operating system is on." Are you meaning I need to place a second hard drive into my computer?
Or....
There is some way to use a Read/Write DVD/CD Drive?

Or...
Is there simply a way to dump that Scratch Disk manually?

Thanks
Shjak Monde

Remember to mount a scratch monkey.

( http://edp.org/monkey.htm )

A different physical drive means a different hard drive, not a partition, not a virtual drive, certainly not an optical drive. Do NOT attempt to use a rewritable optical drive for this. It's doubtful you could get Photoshop to even recognize an optical drive as a scratch disk, but even if you could, it would be highly prone to errors, and its speed would be nothing short of glacial. Hard drives read & write information thousands of times faster than do CD's and DVD's. Also rewritable CD's and DVD's are only writable so many times, and then you have to replace them. With the amount of constant re-writing that happens with a scratch disk, you could use up the rewritablilty of an optical disk within just a few hours or a maybe even a few minutes, assuming it even worked at all in the first place, which again, I think is unlikely.

If you only have one hard drive, that's okay. Photoshop won't die. Just leave the scratch disk on your C drive (and make sure there's plenty of blank space on it) until/unless you want to add a second drive. All that will happen in the mean time is that Photoshop won't run quite as well as it could if it had another drive at its disposal. Occasionally, you may get out-of-memory errors on very large files, but it's not the end of the world. Unless you're a graphic designer working on print-quality images with lots & lots of layers, and assuming you practice good hard drive maintenance (like always leaving at least 20% of the drive as free space at all times) those errors will be few and far between. If one pops up, simply save your work, and then restart your computer. It's just a minor inconvenience.

One hard drive isn't the ideal setup, but then actually neither is two. The best way to go really would be 3 hard drives, one for your OS & program files, one for all your data files, and one to serve as a scratch disk. However, most of us can't do that, as most consumer grade computers can only support two internal hard drives.

It is possible to use an external hard drive (firewire or USB) as a scratch disk or as a primary data drive, but it will be relatively slow compared to an internal drive. In my opinion, external drives are not worth using for this purpose. They're great for backup, but that's about it.

Myself, I have two internal hard drives, one for OS & programs, and one for data. I use the data drive as the scratch disk. This does occasionally cause some problems with very large files, but it's still a better choice than putting the scratch disk on the OS drive.

Again, if you only have one hard drive, don't stress over it. Photoshop might not be quite as happy as it otherwise would be, but it will still do its job.

Thank you very much Chosen that does explain everything much clearer and stops me from experiencing that "Scratch Monkey" Event that Matt is Talking about.. HA HA!
I will stop experimenting on trying illabret Scratch Disks.

However, I am working with very Large Documents in Photoshop.
Some averageing 600 megs.. I know those seem super large for a Skin Texture, But I am getting some great results 3000X3000 at 1000 dpi with 20 to 30 layers.

Talk about going over the deep end but Hey I am enjoying myself.

I just figured that my One Hard drive 250 gigs could handle it.
I can handle waiting a few moments per each save but the locking up and crashing can get old.

Also I have to figure out how to Crop correctly.... Takeing a 3000X3000 image and croping a portion of it witch is about 1/100th of the whole image and it streaches that 1/100th back out to 3000X3000.
that equates out to 300,000X300,000.
Lock up accures.

when what I am wanting it to do is just the oposite.. it should wind up being 30X30

What am I doing wrong?

Signed The Extreemest

Hi Shjak!

Yes, there is a way to dump the contents of the Scratch Drive, at least in PS CS2 (I don't remember if it was there in earlier versions, I'm afraid.)

Just go to Edit > Purge and choose from the drop down whether you want to purge the Undo files, the Clipboard, the History, or All.

If this is something that crops up frequently, you might also want to go to Preferences > General and reduce the number of History States that PS stores.

About the Crop Tool, it sounds to me like you have the Crop Options set to a specific size. Just hit the Clear button in the Options bar when the Crop Tool is active, and it should behave the way you expect it to.

Hope this helps!

One other thing to remember with Photoshop and scratch disks is that old *.tmp files can accumulate if Photoshop crashes. I manually check my scratch disk "Temp" folder if this ever happens before I restart Photoshop.

Thank you Robin this is helpful info.



Now this does resemble what is happening to me.

If the Scratch Disk is dumped each time I close Photoshop or reboot my Computer and not saved, then the Scratch Disk should not continue to grow eating up my 250 gig hard drive. Unless there is a setting that I need to give attention to, to make sure it does empty the Scratch Disk.

I Clean the Hard Drive and Defrag the Hard drive every time before shutting down my computer. However I have Crashed the program many times.
When I Defrag I Notice there is a large growing area of files.. Not neccesarily Fragmented but growing none the less. And No way to see what those files are.

So Where do I find the Scratch Disk folder at, on C:\ Drive?

You're welcome, Shjak.

About the .tmp files, you might find this, from Adobe's website, helpful.

Optimize performance of Photoshop (CS2 on Windows)

It explains how to find, and clear, those files, as well as a bunch of other things that will help you run PS at top efficiency.

(For people reading this thread who are on a Mac, (like me,) here's a link to the corresponding file,

Optimize performance in Photoshop (CS2 on Mac OS)

If you're not running CS2, then just type "Optimize [version number] [platform]" into the Search field on one of those pages to get a list that will include a similar page for your version and platform. (Don't use the quotes, and replace the brackets and the text inside them with your own PS Version and Platform, of course.)

Adoeb has an article titled Memory allocation and usage (Photoshop CS2 that you might find helpful, too.

Also; if you're getting Scratch Disk Full error messages while still having scratch disk space, it's possible that the problem is that the space on the disk is fragmented. PS requires unfragmented space for some of the things it does, so if there's not a large enough unfragged space, that could trigger the error message.

I know that you defrag your disk regularly, Shjak; but for others reading this thread, you might want to try that.

Hope this helps!

WoW! thats the perfect info I was needing..
Thanks again Robin, your a life saver.

Shjak the Humble extreemist