Three Mistakes to Avoid When Stitching

[Editors note: Written by Rachel – the Titus 2 Homemaker.]

As an avid genealogist, I found the Flip-Pal mobile scanner while looking for scanning solutions that balanced ease and quality.

As a homeschooler, I was excited by all the possibilities it presents for additional applications – like compiling portfolios of the kids’ work.  Including even the oversized projects.

The first project I attempted was using the EasyStitch software to save and stitch this large poster my youngest students made.

It’s about two-and-a-half feet high and three feet across.  Unfortunately, I made some mistakes along the way that forced me to re-scan the poster multiple times.  Let me tell you about what I did wrong so you can get it right the first time.

Too Little Overlap

The first time I scanned the poster and ran the software, the eventual output was simply an error message.  Insufficient overlap.  The software couldn’t discern which scans to stitch where.

This seems to have been a matter of misinterpretation on my part.  The back side of the scanner has lines etched into the window, specifically for the purpose of showing where to line up the scanner for adequate overlap.  But the lines on the window may not appear to be quite what you line up with. Rather, the lines can cast a faint shadow on the surface below – casting a temporary line on the thing you’re scanning.  It isn’t far off from the line on the glass itself, but it’s a little off, and is not what you want to use to line up with.  (Don’t worry; the shadow doesn’t show up in the scans, because the scanner uses its own internal light source as it scans.)

I tried again, using the etched lines as the points of overlap, and was able to get results.

Too Much Overlap

At the other extreme is having too much overlap.  This can be a little tricky when you’re trying not to skimp on the overlap and not to miss the edges of the image, but be careful not to duplicate your content by overlapping the scans too far.

If there is duplicate material in the scans, the EasyStitch software tries to fit them in, and you end up with something really wonky, like this.

The key is to go back and scan more carefully, ensuring you haven’t gone over the same areas twice.  The trick in the next section can help, too.

Gaps

Even if you don’t have too little overlap (in general) or too much overlap, you can still have gaps.  I was actually pretty impressed that when I scanned the poster the second time, and got sufficient overlap, the software was able to stitch together virtually the entire picture – even though I’d missed a spot.  It simply left a hole.

With a small piece, it’s easy to keep everything lined up.  Some larger pieces, like quilts, might offer built-in guide lines.  But with a large, somewhat random image like the ocean collage I was scanning, there are no clear lines.  Missing spots is pretty easy to do.

The folks at Flip-Pal suggested the use of a yardstick to keep everything lined up.  I’m not sure whether or not my manner of using the yardstick is what they intended, but it was a considerable help.  All I did was lay the yardstick across the image:

Then I butted the Flip-Pal mobile scanner against the ruler, so I was able to simply slide it along as I moved to each new scan.  That way I only had to line up the scanner once on each row, and then the yardstick did all the work to make sure I wasn’t drifting up or down.  This gave me a much more workable result.

One last detail you’ll notice is the black edges.  That’s because the piece of paper my children used for their poster didn’t have even edges, so the resultant scan is necessarily a but uneven.  The black is where there was nothing to scan.  This is no big deal; I just went into my photo software, selected the black, and changed it to white.  (Depending on your needs, you could also just crop off the edges.)

And now my children’s work is preserved with much better
quality and integrity than a snapshot full of weird shadows.