A press check or printing press check is a procedure to allow a print buyer, designer or agency to validate the printed matter, prior to the job being printed.
This article discusses:
- the basics of press checks
- how to prepare for a presscheck
- a checklist of what to look for
- the list of things for which it is too late once the plates are on the printing press
- additional information
The main goal of a press check is to make sure that the color on press comes as close as possible to the latest color proof that was creating during the proofreading and color proofing stages. By requesting some small adjustments, the color may better match your expectations and improve the quality of the publication. During this quality check, other aspects can be validated as well, such as the paper stock that is used and possible prepress issues. Press checks are typically done for projects in which color accuracy is important such as art books, catalogs, money or stamps. The validation can happen because the customer insisted on it. For art projects it may also be the artist who demands it. In that case both a representative from the publisher and the artist may perform the check.
Due to differences in the printing process, paper stock,… an exact match may not be feasible. Based on feedback from the person doing the press check, the press operator will change settings on the press to fix things. Once an acceptable match has been established, these sheets are signed off and both parties keep a copy. These might be used later if there is still a discussion about the color quality of the final printed and bound publication.
Larger books may consist of many press sheets. Usually not all of these sheets will be checked since that would take too much time. Typically the publisher selects one or a few sheets that are representative of the content of the publication, does a press check on these and trusts the printer to use equal settings for all the other sheets.
A press check takes place once the printing press is set up but before the print run is started. Depending on the production schedule of the printer, this means it might happen at odd moments, such as late in the evening or very early in the morning. The check can take place at the press on the production floor or the printer may have a separate office for this, which is equipped with a light box. For larger orders, printers may offer a press check as a free service, else it may require some insistence of the print buyer.
Press checks used to be pretty common, but they happen less frequently nowadays. There are a number of reasons for this:
- The current crop of color proofing devices is capable of generating proofs that match the printed end result pretty well.
- Printers have adopted procedures to standardize color reproduction, leading to more predictable results.
- Modern presses offer better quality and consistency.
- More books get printed abroad, making it too expensive for the publisher to do an on-site check.
- Bring along the latest revision of the color proofs.
- If a corporate style guide is available which contains the corporate logo or other artwork in the correct color, bring it along. If you are checking a reprint or a job that resembles a previously printed document, bring that as well.
- Pack a swatch book if critical Pantone colors are used in the job and they will be printed in CMYK.
- Don’t forget a loupe to check details and registration. If you don’t have one, borrow it from the pressman (and lose some credibility along the way).
- Make sure you can get to the printer on time! There is NO excuse for keeping a running press waiting.
- The first thing to check is if the correct paper stock is being used. Check the color, weight and texture to make sure that it is the stock that was ordered.
- Scan the entire flats as they come off the press to check the color balance across the sheet. Flat tints should be uniform.
- Check if the content is consistent with that of the proof. Look for missing elements and make sure the latest changes that were done for the last proof also appear on the printed sheet. This validates that the printer used the correct final revision of the layout.
- Fold down the press sheet or cut out the trimmed pages. This allows you to see what the final bound result will look like. If the job includes crossovers make sure that these are consistent in quality and density.
- Check the overall color quality of images. Pay special attention to flesh tones.
- Check if the colors of the corporate logo(s) are correct.
- Images should not be too heavy or dark due to excessive dot gain.
- When the sheet is cut up, putting flat tints from one side of it next to the same tint from the other side of the sheet makes it easy to check color consistency.
Modern presses have automatic registration controls and other mechanisms to improve the quality and consistency of the printed result. The use of CtP also reduced the risk of artifacts during plate making. It still is useful to look at the technical aspects of the press sheets:
- Check the registration of the press. Bad registration can introduce color casts and affect the sharpness of images and screened type.
- Check for printing artifacts such as broken type (such as vanishing thin strokes), scratches, hickeys (odd little circular spots that are caused by dust), spots or ghosting.
- Check for prepress and plating artifacts, such as scratches. Check accents and other special characters as these sometimes get mangled if a different RIP is used for creating the plates. Also check some headlines and body text to see if there is no reflow of text compared to the final proof.
During a press check, it is too late to complain about typos or other layout issues. These should have been taken care of during the proofreading stage. It is also too late to request major color changes. There is a limit to what pressmen can still do on the press. This is again something that should have been dealt with during the correction cycle.
While it may be possible to cancel the press run and do last-minute corrections, this will cost money and delay the job. If you insist on this, make sure you understand who is going to pay for it and what the impact of the delay will be.
In November 2011 I put up a poll on this site asking visitors how much press checks are still used. As with any poll, the results need to be taken with a grain of salt but they are interesting nevertheless.There is also a thread on the b4print forums to share opinions about press checks.
The need for press checks
- Sometimes for a few select jobs (44%, 72 Votes)
- For all or most of the orders (26%, 43 Votes)
- For quite some jobs (12%, 20 Votes)
- Never (10%, 17 Votes)
- Not anymore (7%, 11 Votes)
Total Voters: 163
A separate page on this site contains the results of a November 2011 poll about the importance of press checks.
The best list is that on graphic-design.com.