Questions about running 4 colour

Hello, I love to try out 4 colour printing on my Heidelberg windmill and wanted to see if there is any tips on achieving this?
As for separating the colours in photoshop would I need to copy and paste each channel and convert the image to bitmap?

thanks for your help!

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First you need to convert your image to cmyk an then print separations

You may want to experiment with different line screens as well. If you go too fine (133 or 150 lpi), you’ll probably get a lot of fill-in. Precision with your inking is probably crucial.

The order that you print the colors in, is to be considered as well, as phase4 implied by saying cmyk (cyan, magenta, yellow, black), as opposed to ymck (yellow, magenta, cyan, black).

This is because of two factors: 1) almost always, the amount of ink area put down by the yellow plate, is more than for any of the other colors, and 2) ink adheres to the paper better than it adheres to previously printed layers of ink.

So, you don’t really want to print yellow first, because then a large part of the succeeding colors will have to stick to the yellow ink instead of to the paper.

So, I would try printing cyan first, magenta second, yellow third, and black last (the black usually has the least amount of coverage).

Also, be sure to use actual process colors, because they have transparent pigments and are supposed to transmit light. What you are doing in process printing is printing colored filters on the sheet, where the light will go through the ink films, reflect off the sheet, and then come back again to the viewer’s eye.