Quick colour fixes: Vibrance, Toning, Threshold and more

Some colour adjustments need only a slider or two. Paint by Zaweba collects a dozen of them, each quick to understand and each with its place. Here's what they do and when they're worth using.

Tone and contrast

Equalise spreads the picture's brightness values evenly across the full range. On a flat, foggy photo it can reveal hidden detail; on a normal one it often looks harsh. Try it, and use it at reduced opacity if it's too much.

Threshold turns every pixel pure black or pure white depending on whether it's above or below a set brightness. That's handy for turning a scan of a drawing or handwriting into clean black and white, or for making a stencil-style graphic.

Posterise reduces the number of tones in each channel, giving flat bands of colour like a screen print. A few levels makes a bold graphic; more levels gives a gentler effect.

Invert flips every colour to its opposite, turning a picture into its negative. Useful for scanned film negatives and for some masking jobs.

Colour strength and balance

Vibrance increases colour strength, but gently, with a lighter touch on colours that are already strong. That makes it kinder to skin than plain saturation, and often the better choice for making a photo livelier.

Desaturate removes all colour in one go, the quickest route to greyscale.

Colour Balance nudges the picture's colour towards or away from a colour, which makes it a direct way to correct a cast or to warm up or cool down a photo by a small, controlled amount.

Black and white and toning

Black & White converts to greyscale with control over how each colour turns grey, and on-image drag lets you press on an area and drag to make it lighter or darker. Press on a blue sky and drag down to darken it, as a red filter would with film.

Toning applies classic print tones: sepia, cyanotype, selenium, split tone, platinum and gold. Each gives a black and white image the colour of a traditional darkroom process.

Sepia is the quick single-tone version, warm brown, one click.

Duotone makes the picture from two colours, a classic printing technique that gives rich, graphic results.

Which to reach for

For a quick boost, Vibrance. For greyscale with control, Black & White, then Toning or Duotone for colour. For a graphic look, Posterise or Threshold. For a colour cast, Colour Balance.

These are fast because they're focused. When a job needs more, Curves, Selective Colour and the other fuller adjustments are there, but many pictures need nothing more than one of these.

Wrong tool for the job

Desaturate when you meant Black & White is common. Desaturate gives you no control over how colours turn grey, and skies and skin can end up the same dull grey. Black & White lets you separate them.

Equalise on every photo is another. It's a rescue tool, not a finishing one.

And watch Threshold's level. A small change can make a drawing lose its thin lines or fill up with noise.

All of these are quick to try and quick to undo. In Paint by Zaweba they're a good first stop when you want a result in a few seconds.