Halftone & Retro Print Effect Generator

What this tool does

The image you load is split into per-plate ink amounts and screened again with a halftone dot grid, each plate at its own ruling and screen angle. Three printing methods are available: CMYK four color process, single plate monochrome, and spot color with two or three inks in the manner of a risograph or a screen printing shop. Presets cover offset printing on coated stock, newspaper printing, a doujinshi monochrome interior, a risograph duotone and a retro print look. The screen angle and registration offset of every plate can be set by hand. The result exports as a PNG at the physical pixel size the print width and the output resolution ask for, and the settings export as JSON.

• Adobe: Color settings and rendering intents — Official reference; checked 2026-09-06

Where this fits in your workflow

• Mocking up a doujinshi cover, a zine or merchandise so a client or a printer can see it with the character of the final print.
• Treating halftone grain and registration misalignment as a deliberate part of the illustration instead of an accident.
• Checking, before you commit to a print method, how a drawing holds up once it is reduced to two risograph inks or to a single black plate.

How to use it

1. Pick the preset closest to the print method you have in mind, then drop your image onto the picker.
2. Switch the printing method between CMYK, monochrome and spot color. Spot inks can be chosen from the list of standard risograph colors or set freely with the color swatch.
3. Under Halftone screen, set the screen ruling, the print width, the dot shape and the dot gain. A narrower print width magnifies the screen so the individual dots become visible on your display.
4. On the Plates and paper panel, add misregistration, density variation, dry-out, and the color and texture of the stock.
5. In the plate list, type an angle and an offset for any single plate. Only the plates you touch leave the automatic distribution, and Reset plate adjustments puts them back.
6. Flip the preview between Processed, Source and Split to judge how far the treatment has gone.
7. Read the Warnings block, then export the PNG with Export at high resolution and the settings as JSON.

What each control means

Screen ruling (lpi)

How many halftone dots sit in one inch. The higher the number, the finer the screen. Around 175 lpi is typical for offset on coated stock, 85 lpi for newsprint, and 60 lpi for a doujinshi monochrome interior.

Print width

How wide this image will physically be printed, in millimeters. Together with the screen ruling it decides how many pixels one halftone cell occupies on screen, and the current cell size is shown right under the field.

Output resolution

The resolution the sheet is printed at. With the print width it fixes the pixel size of the exported PNG, and on its own it fixes how many pixels one halftone cell gets there: the output resolution divided by the screen ruling. Below roughly three pixels per cell the screen cannot resolve.

Dot gain (TVI at 50%)

How much the ink spreads into the paper, fattening the dots and printing darker than requested. The value you enter is the tone value increase on the 50% patch itself — the amount that patch darkens by — which is exactly where a press operator and the printing standards measure it. Measured figures are about +14% for coated offset stock, +22% for uncoated and +26% for newsprint. The risograph and retro presets have no standard to follow, so they carry deliberately heavier stylistic values. Coverage of 0% and 100% is preserved and only the midtones darken.

Misregistration (offset and jitter)

How far the plates sit out of register with each other. In CMYK the black plate is the reference, so line art stays put while the color plates shift around it.

Per plate angle and offset

Values you can override one plate at a time in the plate list, up to plus or minus 90 degrees and plus or minus 3mm. Any plate or field you leave alone keeps following the offset, the jitter and the random seed.

Density variation and dry-out

How much the ink laydown wanders across the sheet, and how much a solid breaks up and skips. The variation scale sets the size of the mottling pattern in millimeters.

Sampling

How many samples are evaluated per output pixel. Two or more removes the false moiré that appears where the rotated halftone grid interferes with the pixel grid of your display.

Reading the preview and the exported result

• The plate list on Plates and paper shows the screen angle and the registration offset of every plate. Misregistration is invisible in flat solids; it only shows along edges and at the border of the image.
• If you see fine stripes instead of dots, the screen is not being resolved at this preview size. Lower the ruling, reduce the print width so the screen is magnified, or raise the preview limit. The Warnings block reports the same diagnosis.
• Export at high resolution re-renders at the physical size the print width and the output resolution ask for (210mm at 300dpi gives 2480px) rather than at the preview size, and writes that resolution into the PNG. The size and the effective resolution are shown above the button. A large image can take tens of seconds to export.
• In spot color mode black never becomes a neutral black; it settles into a deep navy or violet. Two inks cannot mix a neutral, and that limitation is precisely what a risograph print looks like.

Bringing the export into Clip Studio Paint

1. Open the exported PNG with File menu > Import > Image in Clip Studio Paint and it is placed above the layer you were editing as an image material layer. On Windows and macOS you can just as well drag and drop the file onto the Layer palette to import it the same way.
2. To reposition or resize it, pick the Object sub tool from the Operation tool group in the Sub tool palette, select that image material layer, and drag the handles that appear to move, scale or rotate it. Image material layers cannot be drawn on directly with a drawing tool; if you need to paint on it, convert it to a regular layer first with Layer menu > Rasterize.
3. To blend it into the artwork underneath, adjust the blend mode and the opacity at the top of the Layer palette. This is the workflow for a doujinshi cover design or a processed illustration for social media, where the export is one layer stacked on top of the rest of the piece.
4. This PNG reproduces the look of a printed sheet; do not use it as your print submission artwork. Converting an image that already carries a halftone screen into submission data doubles it with the screen the print shop applies during platemaking, which is exactly what causes moiré. Build the data you submit from the original artwork instead, and check it with the print preflight tool before you send it in.
5. Reach for Export at high resolution when you want to see the halftone grain at a size finer than the preview shows, or when you want to check a cover or merchandise mockup at its physical size — the file carries its resolution, so it opens at the print width you set. For a quick look at the overall effect, the on-screen preview is already enough.

How the halftone and ink model works

A dot is drawn from a single rule: a point takes ink when its distance from the centre of the halftone cell is closer than a threshold. Distance is Euclidean for a round dot, the larger of the two axes for a square and the sum of them for a diamond. The threshold comes from a table that inverts the distribution of those distances, so the inked area lands on the coverage that was asked for; until neighbouring dots touch it is the same value as the radius whose area matches exactly (r = s × √(a ÷ π) for a round dot of side s and coverage a), and past that the dots merge until only the corners of the cell are left white at 100%. Because the polarity is never flipped at 50%, the pattern does not swap over between 49.9% and 50.1%, and a 100% solid really covers 100% even with round dots. Dot gain is applied as a coverage curve rather than by inflating the radius: a + (TVI ÷ 100) × sin(π × a). The sine term vanishes at both ends, so 0% and 100% stay put, and at 50% the coverage rises by exactly the TVI you entered. The increase peaks at 50% and falls to 0.707 of that at 25% and 75%, which is the shape measured TVI curves actually take. The input is capped at 30% because beyond that the curve stops being monotonic and the deepest shadows would start getting lighter as you add gain. The CMYK screen angles are 15, 75, 0 and 45 degrees, the classic arrangement that minimizes the rosette moiré between four plates. Color is composited as a product of measured ink transmittances in linear light instead of the idealized ink formula, which is why a solid of cyan, magenta and yellow lands on a warm dark brown-black rather than a pure black, exactly like a real three color overprint.

Accuracy, beta status and what is out of scope

This tool is in beta. The halftone, ink and paper models are simplifications tuned to reproduce the look, not a color managed simulation, and the real sheet will change with the press, the stock and the platemaking. Do not use it to decide whether data is ready for submission; check that with the print preflight tool instead. It is not a substitute for a contract proof either.

• The CMYK estimate used for separation is an sRGB based approximation, not a conversion through an ICC profile. Because black is built from all four inks, the theoretical total area coverage goes past the usual submission limit.
• Only AM screening, that is a regular halftone dot grid, is modeled. FM or stochastic screening and hybrid screens are not reproduced.
• The exported pixel count is capped by memory. A request past that cap is written at a lower effective resolution, which is shown before you export.
• Spot mode is limited to two or three inks. Beyond three there are not enough well separated screen angles left to avoid moiré.

How your image and settings are handled

Loading and processing both happen entirely inside your browser, and your image is never uploaded anywhere. The heavy rendering runs in a Web Worker in that same browser, so no network request is involved at any point. Your settings are kept in localStorage on this device so the tool comes back the way you left it; the image itself is never stored.