Printing & Design Tips: November 2002, Issue #16

What to Look for on a Press

The following is a short list of what to look for when reviewing press sheets at a press inspection. An entire book could be written on this subject; this is by no means a comprehensive list, just a brief overview.

  1. Make sure the paper is what you ordered (weight, color, and finish).
  2. Make sure no images or copy have been dropped, and check your last blueline against the sheet to make sure all corrections have been made.
  3. Make sure all colors are in register (spot colors as well as process colors). Start by checking the registration marks, then check the rest of the sheet with a loupe (linen tester, printer's glass). Check trapping.
  4. Fold the sheet to check crossovers. Ask the pressman to fold and trim the press sheet by hand into a signature. Make sure colors, as well as other elements, match on crossovers.
  5. Check the proof for pleasing color (particularly colors of such "memory" elements as skin and grass).
  6. Match the sheet against the last color proof.
  7. Check for broken type or blurry type.
  8. Check for uneven color, particularly in solids. Make sure color is consistent across the sheet. Check screens and color builds.
  9. Check neutrals for any color cast. Match the colors of the printed piece to the colors of any companion pieces in a marketing package such as brochures and envelopes.
  10. Look for printing errors such as slurring, doubling, scumming, hickeys, ghosting, mottling of colors, etc.
  11. Check everything one final time for glaring errors and the overall look of the piece.
  12. Ask the printer to number the sheets as pulled and ask that ink densities be noted on the sign-off sheet. Remember that color will still vary slightly even after you sign off on the job. Your sign-off sheet is the goal, the "contract proof" to which the printer will run the rest of your job. Keep a sample of the final sign-off sheet so you can match it to the piece once it has been delivered.

Defining Spot Colors in Page Layout Programs

Your color ink-jet printer can easily produce a lovely color proof that will bear no resemblance to what an offset press can print. Therefore, before you hand off your disk and composite proof to your print provider, check the following:

  1. If your job is to be printed in process color (4CP), make sure you have defined your color model as CMYK (not RGB). This option is usually in the color definition dialog box in your page composition software, usually under the edit menu. In the same box, deselect spot color. Then print separations as well as a 100 percent to-size composite of your file. You should get four separate sheets of paper, one for each of C, M, Y, and K (cyan, magenta, yellow, and black or "key").
  2. If your job is to be printed in spot colors, make sure you have defined your color model as Pantone Coated or Uncoated (or whatever other spot color formulation you use). In the same box, select spot color. Then print separations as well as a composite of your file. You should get only as many pages as your spot colors number (for example, one for black and one for PMS 286).

    If your spot colors show up on process plates (sheets of paper), or vice versa, the same will happen at your printer. Using your ink-jet or laser printer, resolve these issues before submitting your job.

As a final note, if you create vector art in an illustration program and apply the same colors to your drawing as you used in your page composition software, your placed eps art should separate properly when you print proofs. However, if the names of the colors given by your illustration software and your page composition software differ even by one character, items in these differently-named colors will print on separate pages. Again, it is best to see these problems in your separated proofs so you can correct them before submitting the job to your offset printer.

[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.]