Scanning simple line art and keeping it as pixels

In this movie, what I'd like to show you is taking exactly the same image that we scanned in the previous video that's called simple line art scanned to vectors. I'm going to show you a little bit different way to treat this image. In this case, we're going to scan an image as pixels, and plan to leave it as pixels, rather than take it to vectors. When would you do this? Well, let's say that you didn't have a program that worked with vectors, or you wanted to put this on a Web page as a JPEG file rather than as a vector-based file. What I want to show you is how to capture simple line art, some adjustments we're going to make to give you the highest quality image possible.

First thing we want to do is we want to enlarge the view of our image a little bit. I want to just talk about our image. Remember, before, we did the 16 bit to 1 bit which worked really well for converting to vectors because we had a very consistent edge of our pixels. But if we're going to capture and print and use this image's pixels, you see it's a nice clean edge, but it's kind of rough because of all the pixels along the edge. So what we'd like to do is create a little bit smoother-looking edge. And the way we do that is we're going to convert this image instead of using 16 bit to 1 bit, we're going to do 16 bit to 8 bit, and when I make this adjustment, I want you to watch this edge.

Do you see how much smoother that gets already? And it is. It's a softer edge, but to the human eye, which is what we care about, it actually looks like a higher-quality edge. See that's very stark, when we go to 1 bit, this is 8-bit. It's a grayscale edge. So we're going to go from a final image of 1 bit to a final image of 8 bit which is going to have grayscale values along the edge. So we end up with a nice softer edge, still very consistent and smooth because it's uninterpolated, but just a little bit softer so it blends in with whatever the background is.

Now, one of the consequences of going to 8 bit, and I think you can already see it, watch the image. I'm going to go back to 1 bit again. See how the background is very white, and the line art is very black. When we go to 8 bit mode, things get a little muddier. And in fact, you can see how muddy they are, and let's go ahead and use our Densitometer. You're going to, right off the bat in our first set of projects here, see how important and useful the Densitometer is. Notice when I'm measuring the background, we've got 7% or 8%, and K, and K stands for Black, as in CMYK; Cyan, Magenta, Yellow, and Black.

K is the designation for the black ink, and typically we're using our percentage from 0 to 100%. So, notice that when we're in 8 bit or Grayscale mode, there's actually 7% grayscale value in that background. So, what we'd like to do is get rid of that. The easiest way is to go to our Histogram tool, and what our Histogram tool allows us to do, is we can adjust the Highlight value and the Shadow value if we want to, and notice that this start with 7% or 8% here. And as I move in my Highlight value, notice what happens there.

Do you see how the values go to 0? Now, I've got a full 0 in the background and a full 100%, and then a little bit of grayscale value along the edge which gives us our nice smooth transition. When we look at this histogram, you can easily interpret these two ends of the histogram. Very high contrast file. This is the white paper background, and this is the actual line art itself. So if we want to take the whole background to pure white, we just pull our Highlight value all the way past that white background, and then everything is 0, and then we have the gradational edge and then we're into the black.

Now, can you adjust the shadow end? In some cases, you can. In this case, it really doesn't make too much difference what we do with the shadow end as long as we don't pull it in too much. So we can fine-tune that edge, and then we're going to go up to Scan Dimensions and we're going to check to make sure we still have our 600 pixel per inch, Optical Resolution, and no dimensional change here, everything is at 100%. And we're just going to change the name of our file from Black-and-White to Grayscale, and keep it as a TIFF and we're ready to rock and roll here. All right! So we're just going to go right over to Scan now, and then click on the Start Scan.

You'll notice that once the scanner stops warming up here and the scan begins, that it's going to occur a little bit slower than that simple 1 bit black-and-white scan we did. Why? Because it's capturing eight times as much information. Then as soon as the scan is complete, this button here becomes an Open image file button, and we're just going to click on that, and we're going to open this file up inside of Photoshop. What I want to do is I want to compare these two edges for you, so you can see the difference between them. See, this is a very hard harsh edge which is perfect for going to vectors.

This one, you see that nice gradational edge along there. That's what provides a nice soft view to the human eye. Notice that when you look at these side by side, they're both very high quality edges. But when you print this or if you look at this on a Web page, particularly at low-resolution, this will appear to be a much higher quality edge, because you'll get rid of that starkness that you have in the 1 bit black-and-white file. Now, are there some circumstances where I could create and print 1 bit black-and-white images? Sure! For instance, if I were going to use this on a fax machine, the image on the left, the 1 bit black-and-white, would be great for a fax machine because fax is typically going to deal with line art that either go black or white.

So you don't need the grayscale version. And it makes very, very small GIF for instance on a Web site if you go to small logo images. But for most high quality, high- resolution use for a line art like this, you're actually better off going in the Grayscale mode. So, there are two different ways to handle simple line art, and depending upon how you want to use them in the final analysis, you've got lots of tools and creative possibilities.