Most print problems with black start in the design file, not on the press. A designer sends a page that looks correct on screen, the printer pulls a sheet, and suddenly black text has a colored fringe or a large black panel looks washed out. The fixes are simple, but they have to be decided before the file is exported.
Single black and overprint
A single black (K100 only) is the normal setting for black text. When that text sits on a light background, overprint is usually the safest option: the black plate prints over whatever is underneath instead of knocking it out. Turn it on for small black type and thin rules. If the text is reversed out of a dark background, or if it sits on a photo, do not overprint it, or the type will disappear into the image.
Overprint only helps when the whole file agrees. Many designers switch it on in the layout document and forget that placed images and PDF exports can carry their own settings. Ask the printer to check the separations preview before plating.
Rich black for large solid areas
A large solid black made from K100 alone often prints flat and slightly brown, and it shows scratches and uneven ink laydown. Printers usually recommend a rich black mix instead. A common recipe is C20 M20 Y0 K100, which stays stable on press and can be adjusted a little darker without turning blue.
Total ink coverage matters as much as the recipe. On coated stock, keep the four-color total at or below 300 percent. Above that, the sheet may not dry, ink can set off onto the following sheet, and the dark areas can mottle. The C20 M20 Y0 K100 mix sits at 140 percent total, which leaves the press plenty of room and still reads as a deep black.
Small type, thin outlines, and the software you use
Small text with fine outlines is where raster files fail. If 6 pt type is placed in Photoshop and output at 300 dpi, the edges pick up softness and the counters start to fill in. Set small text directly in Illustrator, InDesign, or CorelDRAW so it stays vector. Large display type with effects can stay in a raster file if the resolution is high enough, but plain body text should not.
Keep outlined text to a minimum as well. Once letters are converted to curves, hinting is gone and thin strokes may print lighter than expected.
Body text sizes for magazine work
For magazine body copy, 7 to 9 pt is a practical range on coated paper. Below 7 pt, serif faces with fine hairlines begin to break up, especially when the text is four-color black rather than K only. Print a specimen sheet from 1 pt to 100 pt at actual size and compare it against the final stock. A screen preview at 100 percent will not tell you how the letters hold on paper.
Preflight checks before export
- Black text set to K100 only, with overprint applied where it belongs
- Large black panels built with a rich black mix and total ink below 300 percent
- Small type kept as live vector text, not raster layers
- Fonts embedded, or converted to outlines after a final proofread
Save these checks as a preflight profile. The next job will take a few minutes to review instead of a reprint to correct.