"When you scan a sketch into your computer, the lines are often light and have fuzzy edges. Resizing the scan blurs or pixelates the image. You can use Photoshop to darken the lines, but they’re still not going to be as clean and sharp as if you vectored the sketch.Vectoring your scanned sketches is great for comics or other artwork, and is especially handy in the process of logo design." Full Tutorial
