Preparing Files for the Printer
Here are a few last-minute items to
remember when preparing document files to send to your printer.
RGB vs. CMYK
It is very easy to forget to change
the color space of the photographic images in your document.
In most cases you start with an RGB JPEG image. Either you
have downloaded the image from the Internet, or you have
brought it into your computer from your digital camera.
Or perhaps you have scanned the image or brought the image
into your layout program from a photo CD. In any of these
cases, you may be working with an RGB JPEG without really
thinking about it.
Your offset print provider, however,
will need to have the image you submit be a CMYK TIFF (less
likely to lose image quality than a JPEG). Changing color
spaces from RGB (a light-based color space used for video
monitors, the Internet, etc.) to CMYK (an ink-based color
space used for offset printing) can alter the colors in
your images. Therefore, to avoid surprises, it is better
for you to make this color conversion before placing the
images in your layout and submitting the final version of
your art file.
Resolution of Placed Images
Remember to provide images with adequate
resolution. The rule of thumb is to double the printer’s
line screen at 100 percent of size. That would mean 300
dpi photo resolution at 100 percent of size for a print
job that will use 150-line halftone screens.
Using a 72 dpi image from the Internet
may look fine on your computer monitor, but the final printed
product will look blurry. In addition, taking this 72 dpi
image and upsampling (also known as interpolating) it to
300 dpi will also provide you with a blurred image. To be
safe, scan the image at 300 dpi at the size you will need
it in the final layout.
Another good rule of thumb is to make
any modifications to the image in the photo-editing program
before you place the image in the layout file. If you rotate
the image, do it in Photoshop before you place it in Quark
or InDesign. As noted before, enlarging the image is a bad
idea, but reducing it is ok, and you should do this in Photoshop
before placing the image in the layout file.
A Mock-Up Is Worth a Thousand Words
Give your printer a mock-up of the
final printed piece. Nothing communicates what you expect
better than a sample.
This goes for duotones as well. Get
a sample from another publication, cut it out, and submit
it. Tell the printer it is the target, the prototype of
what you want.
It doesn’t hurt to clip a sample
of the unprinted press sheet, showing weight, finish, and
coating, to your mock-up, as well as PMS chips showing any
match colors. Also, note what colors you will build (process
Write notes to your printer on the
mock-up, noting placement of dull or gloss varnishes, where
the process color will go (are the photos 4-color, duotones,
or black and white), where any tinted varnishes will go,
etc. Specify whether you want a flood or spot application
of aqueous coating, varnish, UV coating, or film or liquid
lamination. Don’t forget to knock out areas that will
need to accept ink (either hand-written areas on reply cards
or areas receiving ink-jetted address information).
Note any heavy ink coverage, explaining
how it will be handled (a single hit of ink, a double hit,
or a tinted under-color application).
If undersize pages (short pages) will
be included in the final printed piece, include these, to
size, in the mock-up. And note any special finishing techniques,
such as die-cutting, perforating, special folds like gatefolds,
As you create this mock-up, you will
probably see additional elements you will want to either
note or actually include as a physical sample. The more
closely your mock-up and accompanying notes match your vision
of the final printed piece, the better. Don’t assume
the printer knows what you want. Show him, and you will
be happier with the result.
As a final note, it is prudent
to create this mock-up early in the process. Discuss it
with your printer, in person. Also, discuss distribution
issues with your printer at this time. Problems may arise
that you’ll want to address (such as what adjustments
to your printed piece may be necessary to ensure its mailability
at the greatest postal discount). The earlier you discuss
all variables, the less chance there will be for a mistake
or a panicked race to make last minute corrections before
submitting the files.
[Steven Waxman is a printing consultant. He teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.]