Convert PDF to Grayscale Colorspace (One Plate)

AcePrint generates RGB colorspaces. This is because it can represent all colors. Generally, your printer’s prepress department will change to their desired ink settings when imposing the pages and burning their plates.

If you want to remove the color and use only grayscale, you can do that with Acrobat Pro↗ or with Ghostscript↗. Here are two very similar Ghostscript commands to do it:

Create an environment variable pointing to your ghostscript executable:

set GS="C:\Program Files\gs\gs9.20\bin\gswin64c"

Method 1:

%GS% -sDEVICE=pdfwrite -dProcessColorModel=/DeviceGray ^  
-dColorConversionStrategy=/Gray ^  
-dPDFUseOldCMS=false -o grayscale.pdf -f color.pdf

Method 2:

%GS% -sOutputFile=grayscale.pdf -sDEVICE=pdfwrite ^  
-sColorConversionStrategy=Gray ^  
-dProcessColorModel=/DeviceGray ^  
-dCompatibilityLevel=1.4 -dNOPAUSE -dBATCH color.pdf

Note these methods remove some meta data from the pdf file.

References:

https://stackoverflow.com/questions/20128656/how-to-convert-a-pdf-to-grayscale-from-command-line-avoiding-to-be-rasterized↗

https://handyfloss.net/2008.09/making-a-pdf-grayscale-with-ghostscript/↗

https://www.ghostscript.com/↗