| We often think of Adobe Photoshop as a program that deals with photorealistic images. After all, it is the program of choice for separating 4-Color Process, Indexed Separations and Simulated Process Color. But, it is also a very powerful tool for fixing low quality, low resolution line art images. |
Figure 1 shows what appears to be a simple image for a dance studio. It was supplied by the studio as ?the only artwork we have.? On the surface it appeared pretty clean but upon closer examination (use the zoom tool) it was very pixilated. Also, by checking the image size (Image/Image Size) it looked to be high enough resolution.
So why is it this low resolution and rough around the edges? Chances are the dance studio opened the file in Photoshop and didn?t notice that the default resolution was 72 dpi. But, in their case it didn?t matter because all they needed it for was their business card. They never knew they screwed up a nice little piece of art.
The other problem is that the second file they supplied included type. Again, looks good until you zoom in and BAMB (figure 2). It ?ain?t what you thought!? And they want this going down the side of sweat pant legs! Large!
OK, so ?they have what they have.? No use crying about it. The order is in hand and you have promised them shirts. There are a couple of ways you could deal with this.
Yes, you could take this poor original into Corel Trace or Adobe Streamline, but those programs will give you poor results because they will trace ?around? the large (low resolution) pixels and it will still not be smooth.
This is pretty simple on an image like this. Use either Photoshop, Illustrator or Corel Draw and with the ?Pen? or ?Lasso? tool, simply draw around the image converting it into a vector image (Path in Photoshop). Fill the path with solid and there you have it. The type you will have to replace. In this case, no problem. It is a standard typeface called Exotc350. OK, it took me 15 minutes of comparing fonts in the CorelDraw book to find it.
Fix it in Photoshop
This is really one of the easiest ways to fix the image. In fact, this method can be used for images you scan from very small originals that need to be greatly enlarged. First, although our sample image says 300dpi it is obviously not. Since it is considered ?line art? you should get it up to about 600 dpi at the final size. If you scan the image, you should be at 600 dpi or higher. To upsample an image in Photoshop, simply go to Image/Image Size and change the resolution to whatever you want. Make sure the physical size is also the size you want it to end up.
Apply Gaussian Blur
This is going to seem weird. Blur an image to make it sharper? Keep in mind that in order to apply a blur to an image it must be in either Grayscale or RGB mode and can?t be a Bitmap (pixels). If the image is a Bitmap, go to Image/Mode/Grayscale.
Applying a blur to an image like this will soften the pixilation of the edges. Go to Filter/Blur/Gaussian Blur. The Pixel Radius is a judgment call. You want to soften the edge without losing much of the detail (figure 3).
Use a Tone Curve
Next, apply a Tone Curve to the image (Image/Adjustments/Curves). Yes, you could also use Levels. Apply a very drastic Tone Curve. You want to wipe out the highlights and darken the shadows. I like to call this a ?Z? curve. Bring the 0% end of the curve over to 50% and the 100% over to 50% (figure 4). What a difference! Save this file as a TIF or PSD file.
Re-Create Type in Vector Program
The next step is pretty easy. Open your favorite vector program (CorelDraw, Illustrator or Freehand) and import your bitmap file.
Then, simply type in the text and change it to the correct typeface. The enlarged views show how sharp the image is now (figure 5).