Free DTF Artwork Prep Tool
DTF Halftone & Knockout Lab
What is a DTF knockout?
A DTF knockout removes one colour from your artwork so the shirt shows through instead of ink. Knock out black, and your black background simply disappears. The shirt does the dark work for you.
Here’s the catch. Smoke, glows and soft shadows are made of half see-through pixels, and the white underbase prints under every one of them. On a dark shirt, that shows up as a grey haze. Halftone fixes it by rebuilding each soft tone as tiny dots that are either fully solid or fully clear, the same trick newspapers have used for over a century (halftone on Wikipedia). Every dot prints properly or doesn’t print at all. No haze, no mush, no reprint.
How to use it
- Open your artwork. Best at the size you’ll print it, at 300 DPI.
- Pick your knockout colour. That’s the shirt colour. Use the eyedropper to grab the background straight from your artwork.
- Check the Mask view. White prints. Black drops out and lets the shirt show through.
- Tighten the Levels until the background is pure black and your highlights are pure white.
- Set your halftone: pattern, period and angle. Watch the dots change in the full-size close-up.
- Check the Result on the garment colour. That’s roughly how it’ll look pressed.
- Download the DTF-ready PNG and upload it with your order. Done.
Tips that save you a reprint
- Match the period to the shirt and the distance. A chest print people see up close can take finer dots. A big back print seen across the room looks lekker with chunkier ones. Don’t go too fine: the tiniest dots struggle to hold adhesive powder and are the first to lift in the wash. Thick fleece and textured fabric want coarser dots too.
- Line pattern is a mood, not a default. It gives that engraved, vintage poster look, and it’s great on bold, moody artwork. On small prints or fine detail the lines break up, so stick to Circle there.
- The colour trick is why this works on any shirt. Knocking out navy, bottle green or maroon works the same as black: the Lab makes your chosen colour black in the mask, so it drops out. But a file knocked out for black only looks right on black. Printing on navy? Knock out navy.
- Do the knockout at your final print size. Resize a halftone afterwards and the dots smear into grey, half see-through pixels. That’s the exact problem you were fixing.
- Starting settings that work: Luminance, Levels black around 20, midtones 1.0, Circle, period 8 px at 300 DPI (about 37 LPI), angle 45°, anti-alias 1. Then nudge from there.
DTF knockout or halftone: which do you need?
Usually both. The knockout takes the background out. The halftone fixes the soft tones that are left. Here’s how to choose:
- Hard-edged logo on a plain background: knockout only. Switch halftone off.
- Smoke, glows, fades or photos: knockout and halftone together.
- Flat artwork with fuzzy edges and no soft tones: skip the Lab and use the free DTF Edge Cleaner below.
Want the story behind the tool? Read how the Lab works and why we built it.
Your artwork stays with you
The Lab runs entirely in your browser. Your artwork never leaves your computer: nothing is uploaded to us or anyone else.
Rather we sort it out?
Not sure your DTF knockout will hold up on the press? Send it to us for a free check. WhatsApp it to 065 931 1831 or email info@dtfprints.co.za, and we’ll tell you straight what’s wrong, if anything.
If the file needs fixing, artwork conversion is R150 once-off per image, and you never pay it again when you reorder that design.
Got flat artwork with fuzzy edges and no soft tones?
Our free DTF Edge Cleaner sorts that in seconds.
