ColorLayers
The shop profile
Every warning in the program grows out of this panel. It describes not the artwork but your press: what the mesh holds, what fills in, and how far registration wanders.
Four numbers that set everything else
- Lineature. How many rows of dots per inch. Higher is a finer screen but a narrower range of tone you can actually print.
- Minimum line. The thinnest line your mesh holds. It sets the bottom of the printable tone.
- Minimum gap. The narrowest opening that will not fill in. It sets the top.
- Trapping. The width of the overlap for registration. The lighter ink grows under the darker one.
The middle two are best read together. Out of the full scale from zero to a hundred percent they cut the band your press actually reproduces: below the minimum line a dot will not hold, above the minimum gap the openings close into solid. In each ink’s tone control that band is drawn in green, which is the quickest way to see what you are losing.
Measuring them yourself instead of looking them up
Numbers from the internet describe somebody else’s shop. Yours take an evening.
- Line and gap. Output a test of bars and openings from 0.1 to 0.5 mm in steps of 0.05. Print it on your working material, with your ink, through your mesh. The first bar that survives whole is your minimum.
- Lineature. The one where your smallest dot is still larger than your minimum line. If at 65 lines the highlight dot is already below what the mesh holds, your lineature is not 65.
- Trapping. How far registration wanders across a run, not on a perfect pull. Take the worst case you are willing to accept.
Measured once, it lasts. Measure again after changing mesh, emulsion or ink, because each of them moves the boundary.
The rest of the panel
- Artwork resolution. It sets the physical size and how precisely widths can be measured at all. It comes from the file and can be changed.
- Film resolution. 1200 or more, or the screen has nowhere to stand.
- Background knockout. How close to white a pixel must be to print nothing at all. Zero means only pure white.
- Trapping direction. Which ink grows under which. The usual practice is dark over light.
- Registration marks. Crosses at the edges of every film, identical across them. The film grows by a 10 mm margin on each side.
Metallic lives by other rules
An ink marked metallic cannot be screened: the pigment is too coarse to hold a dot. Its minimums rise to 0.2 mm and halftoning is refused, so it prints as a solid.
Which means metallic is a poor choice for anything carrying a halftone. The program will say so, but the decision stays yours.
FAQ
Can I keep several profiles?
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The profile is stored in settings and applies to the current job. If you run two meshes with different minimums, change the number before preparing; named profiles do not exist yet.
Where do I start if I have measured nothing?
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Take an industry starting point, prepare one job, look at the print and correct the number. One real run answers this better than any table.
Why does changing the lineature change the warnings?
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Because it moves the size of the smallest dot. Raise the lineature and the dot becomes smaller than what the mesh holds, so the program starts saying so.
