Back to Dye Printing Tricks & Tips
First of all you have to decide where you are going with your photo/chart/illustration/design. (Click here for a proper use chart.) Photos are more like "paintings" dabs of color (or shades of gray if you are in black and white mode). Look at them up close and you can see hundreds of little blocks of color that blend together to form a sunset mountain scheme. That PhotoShop rendering or scan of a photo is a RASTER. While possible to get a smooth, straight lines, most of these raster graphics are actually made up of competing squares (pixels) of color. You can lighten them, you can darken them, but for the most part they are multicolored bricks all lined up to form an image. They are so many pixels wide and so many pixels tall. Here's the irritating part--if you enlarge them the detail doesn't get better, the bricks just get bigger. The beauty of raster is their ability to be subtly shaded, blending from color to color.
This is a PhotoShop rendering of some text reworked with a mountain background and a sunset. It was used in a tract we produced.
If we zoom in you can see the "straight" line
of the letters are really a stairstep of colored bricks (pixels). The whole
image is a grid of these bricks that are various shades. Even the white
areas are bricks of color. Outside of photo manipulation programs it is
difficult to select a part of the image, since the computer sees it as a
whole unit.
VECTOR graphics are truly mechanical lines. They are straight or curved. When "closed" like a circle, square, or polygon they can be filled in like a coloring book. The beauty of these graphics is they reduce AND enlarge quite well. If you've packed them full of detail, they can be blown up and hold their detail. The down side, they make blends very mechanical. They are not "bricks" of color, like raster graphics, unless you physically draw thousands of boxes and color them...
This is the vector graphic used to create the example from above.
You can zoom in and see the letters are mathematically
created lines. No subtly, no fuzzy edges. Straight, clear, or curved on
a Bezier. Below is a wireframe version of the text as seen by the computer:
This vector-based graphic can be ungrouped, areas can be manipulated,
and the whole thing can be scaled up or down and keep it's sharpness.
Okay, great, now I know the difference between a set of bricks and a set of wires. How come my TIFF won't print smooth and clean? It's probably a problem with resolution. If you scanned in the graphic above, it would go from vector to a raster representation. (You can also do conversions in PhotoShop and exporting from graphics programs). Once that step is done, the resolution is set. If you try to enlarge it, it will start to reveal those little bricks.
Well if you can re-scan the image, scan it to the size and resolution you need for your final output. If you have a postage stamp sized graphic and you have to run it as a poster, zoom in, get a lot of resolution (dots or pixels per inch) and scan it big. The file may be huge, but the data you need will be there. Choose the right format (BMP, GIF, JPG, EPS) for your specific needs.
Depending on the photo you can manipulate it in PhotoShop (or similar raster imaging software that ships with your scanner). You can run a few filters to make a crummy photo a halfway decent piece of illustration. For way too much information on that, click here.
New set of problems. The web is for viewing, not printing. The average screen displays images at 72 dots per inch (dpi). So your FINAL graphics (JPEGs, GIFs) don't need to be more memory intensive than that. Once you get the graphic to the SIZE (width and height) you want, then you can distill the image to 72 dpi to keep your graphics small enough to download sometime this week. Again the trick is to aim for your final output target. The web (right now with the current technology) wants small, easy to download graphics. GIFs and JPEGs can be used perfectly for this use. You can reduce the number of pixels, delete unused colors, optimize and streamline each graphic. But I would keep high resolution copies of stuff you intend to use in printing in the real world.
Use the right format for the right job--click here for a chart.