I have to admit that my first two attempts at stitching were failures. The first photo stitched ok but with some black areas where I had missed overlapping. The second photo was a total disaster with Flip Pal telling me there wasn't enough information to complete the stitch.
Read the instructions!
When you open the Flip Pal software you will get a little menu like this. On the left hand side under Help / Manuals make sure your read the option "How to Scan and Stitch Large Originals." That's where I learned that there should be at least a one inch overlap to get the best stitch. I hadn't done that with the first two attempts.
The photo I've been scanning is an 8x10 of my grandfather and I. For first two attempt I did four scans to cover the whole photo. Armed with the new information I went back and did six scans - three across the top half of the photo and three across the bottom.
Watch those hands!
I took the lid off the Flip Pal and used it upside down to scan my photo which was resting on a desk. I have a tendency to grab the left and right sides with my hands to move the Flip Pal around. Inadvertently this caused me to press the scanning button before I was ready. I must have done that four or five times before I learned the lesson. Try grabbing hold of the corners instead of the ends so you don't have this problem.
With your now properly overlapping scans you are ready to stitch. In the Toolbox Menu select the top middle option - Stitch Scans (see image above).
You with then see this rather plain screen. Press File, then select Open.
Next select the photos that you want to include in your stitch. It's easiest to select the first photo, press Shift (and hold) and then select the last photo to grab all the images at once.
The Flip Pal will then run through a series of five steps while you patiently wait. It can take up to a minute to stitch all the photos.
At the end Flip Pal shows the completed scan. Success! Flip Pla saves the stitched version as a new image.
Here's the raw version before cropping. You can see the wood of the desk surrounding the photo. The black area is part of the image that was not scanned originally. I'm going to crop the desk and the black areas and then my photo will be perfect.
As you can see the stitch software does a pretty nice job! You can't detect any lines where the individual pieces were stitched back together.