Single Channel Layers

If the option Preserve Single Channel Layers is selected, the program scans input PDFs for single channel layers. A PDF layer is recognized as single channel layer if the following requirements are fulfilled:

• All objects in the layer use only one color channel, for example, CMYK objects using only Cyan (C50, M0, Y0, K0), 100% K, grayscale objects, spot color objects (all objects using the same spot color). Even if just one pixel is using another color channel (and be it only at 1%), the layer will not be recognized as a single channel layer anymore. (If you need to use, for example, two spot colors or two process colors, group the two colors in two separate layers.)
• Layers with RGB or Lab objects will never be recognized as single channel layers.

Flattening with option Preserve Single Channel Layers selected.

In the illustrated example, the input PDF contains transparent CMYK objects (1) and a separate layer with black text. As this layer contains only K objects, it will consequently be recognized as a single channel layer (2).

The single channel layer will be excluded from all following processing steps.

The CMYK objects will be flattened (3) and then color managed with the selected ColorServer (CS) and InkOptimizer (IO) profiles.

The single channel layer will not be color managed.

The output PDF (4) will contain the flattened and processed CMYK objects and the unprocessed single channel layer.