Neutralizing Halftone Screens

High resolution scans of a continuous tone print- or even better- a continuous tone negative are the best when making a reproduction.

In order to print photographs on an offset printing press, it is necessary to “screen” images or reduce them to evenly spaced rows of various sized dots. The resulting image is called a halftone.

In our business, we often have to copy halftone or screened images. We’ve been working on some new processes to remove halftone screens and patterns from those images. Sometimes, a printed photo is all we have- the original has been lost, destroyed or, for whatever reason, we just don’t have access to it.

Unfortunately, when we try to reproduce a halftoned image, the new image generated by a printer or a monitor usually shows an undesirable, Moiré pattern. The pattern comes from the array of dots or pixels in the reproduction fighting with the scanned dot pattern in the original image- whether it is depicted on a monitor or on a printed sheet.

For years, when we wanted to reproduce a screened image, we would simply set the camera a little out-of-focus, so the individual dots wouldn’t be a problem. And in the digital age, we would use a “Gaussian blur” to achieve the same result.

But, we always lost details. The halftone process lost details that were present in the original image, and then, blurring a halftone for reproduction would cause a loss of even more detail.

Now, however, we have some powerful, new tools to remove these regular, mechanical patterns from a printed photo. And we can hold onto more detail than we’ve ever been able to, before.

Here are some of our first test images looped with the initial results.