Need to bleed
To bleed or not to bleed
As you plan your project for physical printing, anticipate the need for a border, a bleed, or a partial bleed. Each of these terms describes a specific relationship between the image as printed and the edge of the paper stock. Let’s explore and define.
Relationship of image to edge
Note three kinds of relationships of the printed image to the edge of the paper:
Regardless of whether the work has a full border, a partial border/bleed, or a full bleed, the artist needs to plan ahead. While Illustrator and InDesign have handy document tools that make the visualization of borders and bleeds easy, there is oddly no such explicit feature in Photoshop. One can certainly generate them in the Print function in Photoshop, but this is a terribly indirect way to visualize them in advance. For most newcomers to printing, it’s not at all intuitive.
Visualizing the bleed or border
Our solution is to import the Photoshop image into Illustrator. This is still tricky, but it allows you to visualize the relationship clearly.
This means that every time you want to create a Photoshop document for print with full compositional control over the border or the bleed, you need to factor in the border or bleed dimensions into the total height and width of the Photoshop canvas. Size the document before developing the image:
- Create an empty document in Photoshop, first at the final (that is, trimmed) desired size.
- Zoom out so you can see canvas edges, and turn on rulers. Pull guides out of the top and left rulers and snap them to all four document edges.
- For BLEED: In the Menu, go to Image > Canvas Size… and add 0.25″ to 0.5″ of size to the canvas with an anchor in the center. This will create for you a 0.125″ to 0.25″ bleed all around. The guides will show you the final document size, and the edges of the canvas will show you the bleed.
- For BORDER: do nothing! The border is generated in Illustrator exclusively.
Now, develop your image using this canvas size in Photoshop. The guides help you see where the trim edge will be, for compositional purposes.
Creating crop marks
When done with the image in Photoshop, import it into an Illustrator file to make crop marks:
- Open a new file in Illustrator and create an artboard at the final (that is, trimmed) desired size.
- Place, or drag and drop in, the Photoshop document on the artboard. Notice the relationship between the placed image and the Illustrator artboard size.
- If it is slightly larger than the artboard, you’ll position it so the overhang creates a bleed. Position the image so the bleed area is centered all around (grid snaps help). Align Center using the Artboard as the reference is another way to work with precision.
- If it is smaller than the artboard, you’ll place it away from the edge to create the white space of the empty border. Snaps and aligns can also be helpful in this case.
- From the menu, File>Save As… opens a dialog. In the Format dropout, select Adobe PDF (pdf), which opens another dialog.
- In the Save Adobe PDF dialog, under Marks and Bleeds, check Trim Marks, then specify bleed if you have one. If the document was set up with a bleed area, check Use Document Bleed Settings. More likely, you’ll dial in a 0.125″ or 0.25″ specification in the fields (which are by default linked, so that if you put a number in one, it will show up in all). If you have a border, you can ignore bleed settings.
- Click Save PDF, then check your work by opening the new document in Acrobat Pro.
- In that document, you should see marks in the corners that look like the ones in the illustration.
Trimming
Depending on your desired results, the file will have one of these relationships:
When
trimmed
yields
→
When
trimmed
yields
→
When
trimmed
yields
→
Your service provider typically prints the file on a piece of paper that is larger than your final format to accommodate the trim, and trims to the crop marks using a machine creepily called a guillotine. For example, a final size of 18″ X 22″ would be printed on around a 20″ or 24″ large format paper, and from there it will get trimmed.
However, if you are doing this in a studio I teach or on a large roll printer, you are likely the one who will trim it down using the crop marks as trim guides. The trimming process involves the use of a precise craft knife and straightedge and will be demonstrated as part of the final artwork project.