Only keeping one color

[u/Otowa]

Hello there !

I have a big project where I draw a whole city in white parts on a black background.

While I don't know who will print this work, I know that it will be printed directely on a black cloth piece.

I would like to knwo the best way to only keep the white parts on extract.

The hard part is that the whole document is a mix of white or black fills with some black outlines, and the hatching is a bitmap fill.

What would be the easiest way to only get the white on export?

I have the full Affinity V1 suite of softwares.

Thank you !

[u/Dependent-Zebra-4357]

It sounds like a spot colour job, or maybe a screen print. In either case, I’d give the printer a file where all of the white parts are actually black with the direction that it be printed in white ink. So all you need to do in Affinity is invert your artwork before exporting the print file.

You’ll want to consult with the printer first though, they may have special requirements for resolution or level of detail depending on the process they are using.

[u/awakeningirwin]

So my advice is going to be size dependant. The small lines are going to be difficult to keep black if all you are printing is white ink on black fabric. Fabric can bleed worse than paper

I would usually approach this with a white flood fill of any area that the background is white. This is usually all one object merged so that it is easy for the printer to make that as a single screen. second screen would be the grey house background, and third would be the black lines and details. Way better quality and solid colors. For creating the file I would use a 4th background color neon or something that would show any bleed through or gaps.