> >Pardon my ignorance, but what is a scratch disk? Everytime I >install PS it tells me something about a scratch disk, I ignore >it every time.
Hi Steve, Basically a Scratch Disk as used in Photoshop is an area of memory on your computer's hard drive that you can allow Photoshop to use. Photoshop needs this Scratch Disk because although the file size of the pic you are working on is only, say, 25-odd Mb, the application is using much more than this in order to store data regarding the image that is not immediately noticeable to you, and retrieve it quickly. It's literally like a 'scratch pad' on your desk where you would jot down a phone number that you don't intend keeping, along with masses of other stuff - you know, doodles, girl's phone numbers ;-) Pentax gear prices etc etc. Photoshop does this because the the data it crunches can be far in excess of the RAM that you have either allocated to it (Mac) or is allocated to it (PC) and needs somewhere to temporarily store all this stuff. Hence, it calls this area a Scratch Disk. If you do not allocate Photoshop anything in the way of a Scratch Disk, it resorts to its default setting which is usually 'Startup Disk'. That is, it will automatically use your computer's normal hard drive as a Scratch Disk. Now, you can see the problem here: Photoshop is using your normal hard drive to drop bits of picture data and whatnot everywhere and anywhere it can find suitable space. This is not the best way to do things for Photoshop, and can severely limit the speed of the application, particularly when applying filters, flattening images, saving, etc. You'll find that you can allocate Photoshop several Scratch Disks - I use 5.5 and there are 4 options. But- you need either a seperate hard drive, or a seperate partition on the same hard drive. I have one 6 Gb drive on my main Mac at the moment, in 2 partitions. One partition is about 5 Gb, the other is 1 Gb. I boot up from, and have all my computer's info on the 5 Gb partition, just like any computer would. The other Partition of 1 Gb I do nothing with - there's no data on there, no System Folder, anything. In Photoshop, I go into Prefs and under Scratch Disks, I allocate the first option (Primary Scratch Disk) as my 1Gb partition. End of story. now Photoshop will only use that piece of the computer's hard disk to dump it's clutter and won't touch the rest of the drive at all. This makes things run quicker, and smoother. Soon I will install a 27 Gb drive, and then I can allocate the whole of that 6 Gb drive to Photoshop which should make things run even quicker. I hope I have explained this okay - I'm not into things like data forks or Btrees or whatever - just like using the old digital darkroom, and wanted the best out of the system I have, so I read up on it. This is how I understand it, technophiles will no doubt correct my spelling and grammar, but I think the sentence structure is okay... Best, Cotty ____________________________________ Free UK Macintosh Classified Ads at http://www.macads.co.uk/ ____________________________________ Oh, swipe me! He paints with light! http://www.macads.co.uk/snaps/ ____________________________________
