1 Answer. Sorted by: 1. Assuming your PDF file actually does use RGB (and not an ICC profile embedded in the PDF) then, in order to get R=G=B->C==M=Y=0, K=R, you need to set up a custom ICC profile link. You'll need to tell Ghostscript to use a custom RGB profile in place of default_rgb.icc and a cuustom CMYK profile in place of default_cmyk Convert RGB to CMYK This tool is a free online color converter between two color formats RGB and CMYK. The tool is fast and very simple to use. All Tools (10) RGB: Red (min: 0, max: 255): Green (min: 0, max: 255): Blue (min: 0, max: 255): cmyk (0%, 0%, 90%, 21.57%) Cyan: 0 % Magenta: 0 % Yellow: 90 % Black: 21.57 % RGB Because I don't have designing skills to use Adobe products I use Canva Pro (trial version for now) but the problem with Canva is that the designs you upload to PoD websites are made in RGB colour mode, but printed by manufacturers in CMYK mode. So the idea is to use free online tools to convert the RGB designs to CMYK and upload it to The bigger the dot of a certain color, the more that color is represented. And because the colors are semi-transparent, when combined in various proportions, they create the full spectrum of the color wheel. Image source: USimprints. As opposed to RGB, CMYK uses a subtractive model. In general terms the postscript is used with an RGB color space, and a CMYK color space is just a conversion from RGB to CMYK, so in short, RGB is the "default" color space for PS. In postscript you can explicitly call a CMYK conversion with /DeviceCMYK and you can read more about this in any Postscript related doc, for example this pdf. In the new document window, change the color mode to CMYK (to Photoshop’s default RGB). If you want to convert an image from RGB to CMYK, open the image in Photoshop. Next, go to Image > Mode > CMYK. Before saving your PDF, download and install your color profile and Adobe PDF preset here. VeQvp. Once again, we might be able to tell just by comparing it with the Figma design, because we are exporting it as CMYK, the color difference is fairly noticeable; you can see on the right here again we've got the very vibrant red, the RGB sort of red, same with the yellow, you can see on the left or right here the yellow on the left in our Figma In the new document window, change the color mode to CMYK (to Photoshop’s default RGB). If you want to convert an image from RGB to CMYK, open the image in Photoshop. Next, go to Image > Mode > CMYK. Before saving your PDF, download and install your color profile and Adobe PDF preset here. In fact, you can even avoid converting to CMYK if you desire. The export to PDF/X in InDesign will auto-convert RGB to CMYK based upon profiles. I, personally, always convert PSD files to CMYK for print projects. I do not want to rely on any automatic color conversion. In a C# project with PDFsharp (WPF build) I save a PDF document setting. PdfDocument document = new PdfDocument (); document.Options.ColorMode = PdfColorMode.Cmyk; In the document I draw an image stored in another PDF source and a PNG/TIFF image (depends). When I open the saved document in Adobe Bridge it tells me that both color modes CMYK and PDF/X-4, Colour-managed, CMYK, gray, RGB or spot colour data are supported, as are PDF transparency and optional content For newspaper print, we will need to adjust the total ink coverage to 200% or as specify by your newspaper printer. Problem. Following recommendations from a variety of discussion (see below), I have attempted to use ghostscript to convert a PDF file in an sRGB colorspace (generated by Inkscape) into a PDF/X-1a file, in a CMYK colorspace. The command I have used is the following: gs -dBATCH -dNOPAUSE -dPDFA -sDEVICE=pdfwrite \ -sDefaultCMYKProfile=/usr/share

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