Text or graphics that extends all the way to the edge of the paper it is printed on. Bleeds are used in publishing for graphical effect and for printed tabs. Most printers cannot print all the way to the edge of the paper, so the only way to produce a bleed is to print on paper larger than the final page size and then trim the paper.
To cut out or crop unneeded portions of an image or a page is to crop. Cutting lines, known as crop marks, may be indicated on a print-out of the image or page to show where to trim.
In a saddle stitched booklet the bulk of the paper causes the inner pages to extend further out than the outer pages when folded. When trimmed the inner pages are narrower than the outer pages.
Bleed is needed for every piece of work you create, even if your book has a white border around the whole piece the printer still needs to print it on a larger piece of paper and cut it down to size. There are a few reasons for this but the biggest one is an effect known as creep. In a saddle stitched booklet the bulk of the paper causes the inner pages to extend (creep) further out than the outer pages when folded.
Take a dozen sheets of paper and draw a line 1" in from both ends of each sheet of paper. When each sheet is folded in half the lines will match up perfectly when you hold it up to the light and look through it. Now take all 12 pages and put them together like a comic book. Hold it up to a strong light and look at the lines. They not only don't line up, but the center sheet's line can be as far away from the first sheet by as much as 1/8th of an inch depending on the thickness of your paper. If you draw your artwork right to the edge of each sheet and that page falls in the middle of your book, chances are that the artwork will get cut off. If you make sure nothing important is anywhere near the edge of your sheet, then you can be sure that people will be able to read your book as intended after the printer cuts your book down to size.
If you have an old comic sitting around that you don't mind ruining, take the staples out and spread the sheets in order out on a table. Measure each sheet from left to right and you will see that the center ones are shorter than the outside ones. The bigger the book, the bigger the difference.
If you have spent weeks or months on your project and have placed text or important artwork right on the edge of your page there are a few tricks to make it come out alright. The #1 solution to this problem is to make pdf's out of your pages and then place them in a layout program such as QuarkXpress or someting similar, Shrink them down to about 90% of the final size you wish and center them on each page. This creates a white border that doubles as a bleed. In the finished trimmed book, the thickness of the white border will still vary from page to page but nothing important will be cut off. You can also put a greyscale background instead of a white one, this often has a very nice effect and can indeed look like it was designed that way.
The best way to control this effect is to build your book with bleed right from the start. Decide on a finshed size, we'll use 6.67"x10.25", a very common comic book size. Make your pages 1/2" bigger in both dimensions, giving you a layout page that is 7.17"x10.75". Now draw a centered box to you original dimensions (6.67"x10.25") this shows you what the desired finished size of your book is, and where to draw things that you want to run off the edge of your page. Now we are going to draw another smaller box inside your finished size box, make this box 1/4" smaller in both dimensions and center it. This box would be 6.42"x10" and is sometimes called the "live area". Anything drawn within these confines absolutely will not get cut off by the creep effect. Do not place text or any important images outside of this smallest box.
Now that I've confused you enough I'll leave my email for anyone who has any questions.
Cheers
Jeff Mandryk
jeff@islandprintservices.com
SIPS Comics