Rasterize image for printing

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1

Anyone knows a free program to get an image rasterized, i searching for poster printing, with this dot in middle and dots around. Gimp has only one for newspaper, but iam searing a method for colored prints.

Similar to these https://en.wikipedia.org/wiki/Halftone
Like this
https://print24.com/de/blog/wp-content/uploads/2015/06/CMYK.jpg

2

You can do it with basically any software that have b/w halftone pattern with angle settings and RGB → CMYK converter.

I was doing this very long time ago so maybe there are better ways.

  1. Convert your Image to CMYK.
  2. Extract channels and import them as layers.
  3. Use b/w halftone pattern filter on every layer, and use specific pattern angle for each one.

Here you have 4 examples. I used only 165/105/90/45.

halftone
halftone1920×1440 544 KB

  1. Fill 4 pattern layers with CMYK colors.

Just remember about the layer order. From bottom to top: yellow, cyan, magenta, black.

3

But also – print shops have a standard process which they call “pre-flighting.” This is where they take your inputs and convert them into what is needed for their printing process and machinery, and it is definitely a voodoo art which uses specialized software. If you’re planning to send an item out to be professionally printed, directly ask them what they need from you and then give them exactly what they ask for. Undoubtedly, they will not want you to do any rasterization. “This is what they need to do, so let them do it.”

The cost of this initial step is usually amortized into the print-run. They should be able to show you, on their computers and calibrated monitors, precisely what the printed page will look like. And you will sign-off on it.

It helps considerably if your own monitors are also calibrated. This is why so many graphics people use Macintoshes, but higher-end PC equipment can be calibrated as well.

4

You are correct about sending the printhouse exactly what they ask/want.

On the other hand halftone pattern can be used as artistic ‘filter’ to imitate offset print with the printers that have more pigments/dyes than just CMYK. The printhouse will ask for a TIFF with a specific icc profile for given machine+paper combo.

5

If you want to use it only for stylization purposes, and not print production, there’s a free Blender shader that does that: https://crazypixel.gumroad.com/l/AyqRU