Colour in Optical Illusions

Hero image for Colour in Optical Illusions by Colin Shanley
Hero image for Colour in Optical Illusions by Colin Shanley

Were you aware that you see in black and white in low light. Most do not realise this. But next time you get up in the middle of the night in a darkened bedroom, have a look around. You will see only black and white – no colours. Now scan your eyes over the hero image for this article, above. Let your eyes wander over it. The discs appear to be moving, but they are not – it is a static image.


Even a high-level understanding of the emotions and associations of colours will improve your designs and conversion rates

Hero shot for Colour Psychology Quick Reference Cards, by Colin Shanley
Hero shot for Colour Psychology Quick Reference Cards, by Colin Shanley

Show me the green, because I’m down and feeling blue. If you do, I will be in the pink. If you don’t — either because of that streak of yellow down your back or because of your black heart — I’ll see red. And by the time I’m done with you, you’ll be waving the white flag.


How to mix colours of equal brightness for your colour palette

Hero shot for Mixing Colours of Equal Luminance — Part 2, by Colin Shanley
Hero shot for Mixing Colours of Equal Luminance — Part 2, by Colin Shanley

In this two-part series, I show you how to create colours for your palette that are of equal luminance. In Part 1 I explained exactly what luminance (perceived brightness) and relative luminance (relative to solid white or black) actually are. The way in which screen pixels and subpixels emit light, and the way in which the eye perceives it, makes matching luminance of different colours problematic.


How to mix colours of equal brightness for your colour palette

Hero shot for Mixing Colours of Equal Luminance, by Colin Shanley
Hero shot for Mixing Colours of Equal Luminance, by Colin Shanley

Many designers I meet, especially fledgling or middleweight ones, do not have a genuine understanding of luminance. They know that some colours are brighter than others, that high contrast is necessary for accessibility, and that low contrast can be used for subtlety and aesthetic effect.


Running Sketch in a virtual machine doesn’t work. There is an alternative route…

Hero shot for ‘Sketch in a Virtual Machine? Here’s a Workaround’, by Colin Shanley
Hero shot for ‘Sketch in a Virtual Machine? Here’s a Workaround’, by Colin Shanley

There are many reasons why you might want to run Sketch in a virtual machine. Perhaps you are a developer and wish to work in an isolated environment while you create plugins or assistants. Or maybe you want to check out the latest Sketch beta without messing with your current installation. Whatever your reasoning, you are in for a disappointment — Sketch does not run in a virtual machine.


What are Sketch Assistants and how do you use them?

Hero image for Sketch Assistants article by Colin Shanley.
Hero image for Sketch Assistants article by Colin Shanley.

With Sketch 68 comes a revolutionary new addition to design workflow — Sketch Assistants. In a nutshell, Assistants bring document integrity checking to Sketch. They allow you to define rules against which documents will be checked in real-time. Should anything you do to your document violate any rule, the Assistants pane notifies you and gives you an easy means to resolve it (or, indeed, ignore it).


How to test a legacy colour palette for accessibility and persuade a corporation to adopt changes to it.

Palette matrix of foreground and background colour combinations.
Palette matrix of foreground and background colour combinations.

Accessibility has always been a tough sell. Admittedly, less so than in the ‘nineties, when no prospective client was interested. But even today — more enlightened times — the majority of companies I encounter still prefer to make a lot of noise about accessibility without actually making a serious effort to address it (that is not an exaggeration, and I am talking about household names).

Colin Shanley

Colin has been solving problems and designing applications for more than 30 years. His designs touch our lives every day.

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