The idea of transparent, acetate overlays probably takes you back to college. The clear plastic sheets, on which notes could be scribbled and then displayed at the front of the class using an overhead projector, were godsends to professors thanks to their time-saving simplicity… even if that simplicity left something to be desired from a technological standpoint.
Issues with Acetates
In the printing industry, in the present, it’s a similar situation. Acetates’ speed advantage has somewhat withstood the test of time, at least with regard to manual proofreading. Unfortunately, their overall ineffectiveness has forced the tool to fall by the wayside. In their place, automated systems and digital proofreading platforms have been adopted into the mainstream, highlighting the clear-cut advantages they share over acetates in the process.
During their heyday, acetates mostly originated from printers, who supplied them to clients. The purpose behind them was straight-forward: to check for inaccuracies once a shipment had come in. And, in principle, using them was easy. As the overlay comprised a to-scale print of each insert/ packaging component, all you had to do was place it on top of one to find inconsistencies
Easier said than done though, it turns out. A lot of complications could creep in, compromising the integrity of the proofreading process. For example, while overlaying an acetate hypothetically draws immediate attention to (unintended) inserted characters or defects on a sample underneath, the same isn’t true for characters or portions of characters that are missing.
Of Acetates and Automation
After all, the acetate, which is assumed to be 100% accurate based on the file the customer had already approved, would be physically covering up any characters that should be there but accidentally got removed at some point in the file-preparation process. That leads to another issue, namely when the acetate itself gets printed.
Generally speaking, the acetate is only created by the printer after the file has been converted into a TIFF file to make the printing plates. During the conversion process, errors can be introduced into the file. As the file gets prepared, trapping/ color separations/ barcodes get added, meaning the customer is taking a chance they are overlaying a bad acetate on top of a bad final print. Considering the potential ramifications of a typo, that might be too large a risk.
Ultimately, there are too many uncertainties surrounding the acetate to use it as a substitute for the master file to compare to a sample. The proofreading method admittedly has it benefits, namely its speed. However, if the goal is to compare samples to what has been approved internally, digital proofing systems can accomplish that same task… faster too.
Out with the Old, in with the Digital
Digital files can be loaded in (or hard copies scanned in) and then compared to one another, in a matter of seconds or minutes. That’s compared to hours and days when inspecting shipments from the printer. Ironically, it’s a similar process, as one file gets digitally overlaid on top of the other and the two get inspected pixel by pixel for differences.
Both ways are arguably better than manually going over a master and a sample by eye, character by character. However, there’s simply no comparison between a digital inspection system and acetate overlays.
For print suppliers, printing an acetate is one more expensive step at which errors can be introduced. More materials, labor, and oversight are required to print the acetates in the first place. They also have to be stored in case of a reprint, which can be wasteful, especially compared to the size a digital file takes up.
It all translates to higher costs passed on to the client, who have to first proofread the acetate to ensure its accuracy before even starting to proof samples. Doing so using an acetate means devoting more resources than you otherwise would because you’re actually proofing at a slower pace relative to how you would with a digital system.
It turns out, sometimes the technologically advanced solution is the simplest one instead.