I figured this out. Your call to DrawImage looks like this:
g.DrawImage(_testImage, 0, 0)
Here you have not included the image's width or height. When you do that, it draws the image using its "physical size" so it's the same size whether you're drawing on the screen, a printer, or something else. At least in theory. In this case, however, the program has fiddled with the Graphics object's transformation so it doesn't work out so well.
g.DrawImage(_testImage, 0, 0, _testImage.Width, _testImage.Height)
Now the code indicates explicitly what size to give the image so it doesn't try to get smart. The program's transformation scales it nicely so it fits where you'd expect.
Check out my latest book:
"Expert One-on-One Visual Basic 2005 Design and Development"
Sign up for the free VB
Helper Newsletters at http://www.vb-helper.com/newsletter.html