Halftone and Color Separations

**gwpriester** · 15 October 2023, 11:52 AM

This is one of those long-forgotten features that has been a part of Xara since day one almost. And to the best of my knowledge has never been touched or updated.

I have never used it because it is really the print company's job to do the color separations but it's all there plus 9 different screen/dot options. And a full range of printers registration and other marks.

It's in Print > Options

**handrawn** · 15 October 2023, 01:21 PM

Gary - as I recall those separation and screen/dot options are for printing directly to a postscript printer; I'd forgotten the dot options, still not having a postscript printer cannot check...

**Acorn** · 15 October 2023, 02:49 PM

Originally Posted by handrawn

if I print to PDF I get greyscale, not halftone - but based on what you have previously said, am I right in thinking this does not work in firefox?
if so, can I view it from xara in another browser without changing my windows default,which is not an option at the moment...

You have to twiddle with the :root values.
Up the --line-contrast to a very large value. Increase the --photo-blur to recover the roundness of your 'dots'.
Possibly, also increase the --dot-size. Change --blend-mode to screen.

Use the highest rendered size as the monitor will be showing 96dpi.
Remove Xara dithering.

The rest depends on the image.
You could set its Contone Dark to Black. You could tweak the Transparency settings.

The alternative is to screenshot, paste back into Xara or a bitmap editor and manipulate with the Photo Tool.
I have even brought the screen shot back in as the source image.

As it does not work in FF, copy the URL and paste into another browser.

I refer my learned friend to my opening statement, "No idea if this is of any use."

Acorn

**Acorn** · 15 October 2023, 03:03 PM

Originally Posted by handrawn

Gary - as I recall those separation and screen/dot options are for printing directly to a postscript printer; I'd forgotten the dot options, still not having a postscript printer cannot check...

@handrawn, the bottom block is for colour separation for any printer. If you choose PDF export then you get four registration plates in the document. These are all greyscale so I do not think they help.

Acorn

**handrawn** · 15 October 2023, 03:15 PM

I refer my learned friend to my opening statement, "No idea if this is of any use."

I was interested in how practical it might be... not very it seems if you already have [for example] cartoon software that will export in halftone the way I believe the OP was hoping xara would - but an interesting aside...

it does work as far as I can see in edge...

**handrawn** · 15 October 2023, 03:17 PM

... oh any ide what the screen/dot options are there for, I can't see they make any difference to the separations....

**Acorn** · 15 October 2023, 03:25 PM

Originally Posted by handrawn

... oh any ide what the screen/dot options are there for, I can't see they make any difference to the separations....

No, 'cos those are for PS printers.

I do note that Xara's 'Help' on this is misdirected; a common failing!
Just in!

Screen/dot type: PostScript printers can print halftone dots in a variety of shapes. Generally round dots give the best results but some presses work better with a different dot shape.

Acorn

**handrawn** · 15 October 2023, 04:01 PM

No, 'cos those are for PS printers

indeed... as I thought, thanks

**gwpriester** · 15 October 2023, 04:11 PM

Theoretically this could be used to generate a PostScript file that a printing company could RIP to create 4-color separations for commercial printing. But these days it is easier to create a PDF/X file and let the printing company do the rest.

**Acorn** · 15 October 2023, 06:18 PM

Playing around further, I've found if you make the --photo-blur -1px (yes, negative) and also adjust the --dot-size to zero or close and tweak the --line-colour, you can get some powerful posterisation effects.

Click image for larger version.

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came about with these :root settings:

--dot-size: 0.5em;
--line-color: #8b3f1a;
--line-contrast: 185%;
--photo-brightness: 80%;
--photo-contrast: 250%;
--photo-blur: -1px;
--blend-mode: hard-light;

To do your own interactive tweaks open the browser elements for the page and expand the <head> and the last <style> entry to reveal the :root settings in the Styles window.
You can select most values with numbers and when highlighted, use the Up/Down arrows to increment/decrement.

Acorn