OneTaskBy Tim King · Updated
Duotone Effect
Map a Photo's Shadows and Highlights to Two Colours, Poster-Style
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How the Duotone Effect works
This duotone effect recolours a photo with just two colours: the darkest parts take the shadow colour, the brightest take the highlight colour, and every tone in between is a blend of the two, the look made famous by festival posters and streaming playlists.
How to use the duotone effect
Drop in a photo and pick a Shadow colour and a Highlight colour. The preview updates as you change them. Contrast stretches or flattens the tones before they are mapped, so raise it for punchy graphic results and lower it for a softer, washed-out print. Download the finished image as a JPG, or as a PNG if your original was a PNG.
How duotone works
Each pixel is reduced to its brightness, ignoring its original colour. That brightness then picks a point on a straight line between your two colours: black becomes the shadow colour, white becomes the highlight colour and mid-grey lands halfway. Because only brightness matters, a portrait keeps all its shape and detail while losing its original colours entirely.
Choosing colours
Duotones look strongest when the shadow is dark and the highlight is light, such as navy with pink, deep green with yellow, or purple with orange. Picking two colours of similar brightness flattens the image. For brand work, use your brand's darkest colour for shadows and a light accent for highlights.
Private by design
The photo is recoloured on a canvas in your browser and never uploaded.
FAQ
What is a duotone image?
A duotone is an image printed or displayed with only two colours. Darks take one colour, lights take the other and mid-tones blend between them, which gives a bold graphic look while keeping the detail of the original photograph.
Which colour combinations work best for duotone?
Pairs with a big difference in brightness work best, such as dark blue with pink or black with yellow. Two colours of similar lightness produce a flat, low-contrast image that loses most of the detail in the photo.
Can I make a Spotify-style duotone cover?
Yes. Use a saturated dark colour for shadows and a bright, contrasting colour for highlights, raise the contrast a little, and the result matches the bold two-colour artwork used on many playlist covers.
Does the duotone effect work on transparent PNGs?
Yes. Transparent areas keep their transparency and only the visible pixels are recoloured, so logos and cut-out subjects stay ready to place on any background after you download the PNG result.
See also: all Images tools, Audio, Video & Screen, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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