What a halftone does
A halftone turns continuous tones into dots of varying size. Big dots read as dark and small dots read as light, so a single ink color can reproduce shading and photos. Screen printers use halftones to print gradients and photographic detail with spot colors, and designers use them for a retro comic or distressed look.
Choosing dot size (LPI) and mesh
Finer halftones need finer mesh to hold the dots. A common rule of thumb is that the mesh count should be about 4 to 5 times the LPI (lines per inch):
| LPI | Suggested mesh | Look |
|---|---|---|
| 25–35 LPI | 110–160 | Bold, visible dots; forgiving on press |
| 35–45 LPI | 160–200 | Standard apparel halftones |
| 45–55 LPI | 230 | Finer detail, simulated process |
| 55–65 LPI | 305 | High-detail, CMYK process |
Dots that are too fine for the mesh fall through or clog, leaving blotchy highlights and plugged shadows. If in doubt, go coarser.
Screen angles and moiré
Angling the dot pattern keeps it from lining up with the mesh threads and producing moiré, a wavy interference pattern. For a single-color screen print, 22.5° or 25° is a common starting point. When stacking multiple halftone screens, give each color its own angle, typically at least 30° apart.