Help with Photomerge and how to do suggested solutions

I am using Photoshop CS3 on Windows XP and am having a problem with Photomerge working very slow, not working at all, and not being able to handle more than 2 photos (sometimes it won't even do 2 that have 25% overlap). I found these solutions in a previous thread.

Solution 2: Increase the amount of scratch disk space available to Photomerge.

Solution 3: Decrease the size of the source files.

Solution 4: Reduce the amount of RAM allocated to Photoshop in the Memory & Image Cache Preference to approximately 40-50% and retry.

Can someone tell me if these solutions are correct? If so, how can I do these? If not, what can I try? If I could get detailed instructions (I don't know anything about computers) that would be the best. Thanks in advance for any help!

You need to say what size the pictures are and how they are overlapped.

Also give some indication of what RAM and scratch disk space you have.

The pictures are generally about 10200x6600 pixels. They are scanned images of newspaper (in jpg format) that is too big to scan in all at once, so they overlap significantly. How do I check my available RAM and scratch disk space?

Ben,

You are working with 67 megapixel images. Photomerge is hardly designed to operate with such huge images, and your RAM will be zapped by using such large source images. Any particular reason for the huge file size?

I am scanning the newspapers and that is the size they come out as. Is there a way to change that?

There should be an option in your scanning software to change the resolution and output size. Try something smaller, I'm sure Photomerge will go smoother.

I have often scanned LP album covers in segments, at 600 ppi, and used Photomerge to meld them together. That results in images that are roughly 7200x7200 pixels, or 50 megapixels. Photomerge is pretty quick, given the size of the files.

But yeah, you may need to reduce the resolution of the files you are scanning. You may be scanning at 1200 ppi or higher. For text, I don't think I'd go much below 600 ppi if you want a really clear reproduction, and scan in grayscale or RGB, not the "text" mode, which is 1-bit bitmap and will not likely work well with Photomerge. Turn all descreening or sharpening options off in the scanning software; likewise, turn off all exposure wizards and expose all images at the base manual settings (don't use the scanner software's curves, etc.). You will take care of the exposure, sharpening, descreening, etc. in PS once you have scanned and merged.