Photoshop seems to me like a marvelous software, in my opinion isby far the best out there… is the most powerful, versatile, the greatest. But it still has a problem since previous versions, the weight of the files is huge, we could think that for the information it has the size is reasonable but…

Did you know that we can reduce the weight of the PSD up to 75%?

This is something to think about, if we can reduce so much the information in a PSD it would be because this format is not very optimized, right?. Most people think that’s why there are files with compression, TIFF or JPG… but they agree that keeping the original files in PSD format is much more comfortable than working with TIFF (i don’t think we need to compare it with JPG).

Well, how can we do this? Something as simple as hiding the layers before saving the file, if after that you compress it with Winrar or Winzip you will save a lot more.

Here you have the information of the experiment:

1. Normal PSD: 49,2 MB
2. PSD saved with the hidden layers: 38,9 MB
3. PSD saved with the hidden layers and zipped: 11,5 MB

The new version of Photoshop CS3 is out and we still have the same problem… we will have to wait a little more. Now, if you have to send a PSD via FTP or email… you have no choice than doing this.

Adobe has posted a very detailed and thorough document explaining how to fine tune your PC for Photoshop CS3. Bottom line is (as always): get a fast processor, a ton of RAM, and a RAID 0 array for your scratch disk. Even if you have that, there are quite a few things you can do to optimize your workstation... Cache level preferences, memory allocation percentage, etc., etc. Well worth a read if you spend any significant amount of time in PS.
Adobe - TechNote : Optimize performance of Photoshop CS3 on Windows XP and Vista