Colour is an unparalleled science communication tool.
Got 10 overlapping data sets on a graph? Colour-coding saves the day.
Working with heat maps? Gradients are your best friend.
Making your next award-winning scientific poster? Better prepare a great colour palette!
Colour is context. And it just makes things a whole lot more #aesthetic too.
But, does everyone see colours the same way you do?
With 7-8% of the world population being affected by colour blindness, there’s a good chunk of people who may not see your research in the way you had intended!
So, how can we accommodate for colour blindness in our research outputs?
Let’s get to work on that — starting with a colour blind-friendly scientific poster.
Though first, let’s dive into some science shall we?
What is colour blindness?
People with Colour Vision Deficiency (CVD), or colour blindness, distinguish colours differently from those with normal vision. Colour blindness is passed on through your family, and different types are inherited in different ways.
💡 -Fun fact-
Red-green colour blindness, which is the most common form of CVD, is inherited through genes on your X-chromosome(s) and is more common in men.
But why is this?
Without going too deep into the genetics, this is because women have two X-chromosomes, and so any deficiencies in one chromosome can be compensated by the “spare”.
Men on the other hand with only one X-chromosome, unfortunately, don’t have a spare to work with. 🤔
There are many different types of colour blindness, though some common ones include:
Deuteranopia and protanopia (”red-green colour blindness” - cannot distinguish between red and green, each to varying degrees for different hues)
Tritanopia (often under the misnomer of “blue-yellow colour blindness” - but in truth actually refers to being unable to distinguish between blue and green, purple and red, and yellow and pink)
Monochromacy (can only see grayscale)
Each of these types of colour blindness refer to how a person’s eyes are less receptive to one particular colour - one of green, red, or blue. Because of this, colour blindness can be more accurately described as a green-, red-, or blue-colour weakness.
In cases of monochromacy (and many other types of colour blindness), you can also be less receptive to multiple colours.
If there are so many different types, how can we design for them all?
This is a bit of a grey area.
“You can’t please everyone” is what I might like to say.
But it would be a missed golden opportunity to simply call it quits. There are still ways! 🌟
At the core of it all, a scientific poster (or any research output for that matter) has a major role: to communicate a strong scientific message. So for a poster with lots of visuals, how do you communicate in a colour blind-friendly way?
How to design for accessibility:
1. Steer clear from certain colour combinations
To add to that, we recommend avoiding these colour combos to accommodate for most types of colour blindness too:
Red & green
Blue & purple
Green & brown
Green & blue
Blue & grey
Green & black
Green & grey
Light green & yellow
Does that mean you definitely can’t use these combos anywhere on your poster? Not necessarily.
But it would be ideal to avoid them on a legend, or if you are using them to colour-code certain things where your reader has to clearly distinguish one from another. 🚦
(…and for my fellow molecular biologists in the crowd who love to make cells glow, unfortunately overlapping GFP and mCherry signals on your figures are a colour blind nightmare! Opt to change the colours of your figures without altering your data using Adobe Photoshop, Imaris or ImageJ 😉)
2. Create a colour blind-friendly colour scheme (as best as you can)
With those combinations out of the way, what colours can we still use? 🤔
First think of a colour you like, then head on over to Adobe Color under the Color Wheel tab to check what colours would well work together with it. 🎨
In this case below, I really like a blue motif and am checking to see what could work as a colour blind-friendly accent colour. By simply dragging the colours across the spectrum, Adobe Color will check whether it is safe for an audience with deuteranopia, protanopia, and tritanopia all at the same time.
Once you have a green checkmark, you’re good to go 👍
You can also import these colours directly into Adobe Illustrator if you’re creating your poster in that software. If you haven’t already, try out a free 7-day trial from the Adobe website.
We’ve also prepared a few schemes for you to try out, which have carefully considered:
high contrast with a set of primary colours and an accent colour
the common types of colour blindness
can still incorporate black and white in the scheme as needed (i.e. for text)
All you have to do is copy the picture above and use the eyedropper tool to bring your preferred colour scheme into your software of choice!
3. Use icons and patterns to convey contrast
Colour isn’t the only way to show contrast.
If you have a scatterplot with a red set of data points, and a green set of data points, you could instead replace these with just illustrated icons which represent the data points visually. These icons can either be in grayscale or in colour, as it’s the shapes that people will be distinguishing.
Another simple approach would be to use different shapes for your data points on graphs, or hollow shapes versus filled-in ones.
You could also create graphics that are different in texture to make them easier to distinguish (but be careful of clutter, see point #5 further down this article)
Some easy textures include:
Keep these textures at a very low opacity so that they don’t overpower your graphic. We encourage you to experiment to see what works! 👨🏽🔬👩🏼🔬
4. Labels, labels, labels!
In all other cases where you have to use certain colours, having a clearly-labelled graph or illustration on your poster will help out lots. This is especially important for any detailed diagrams you might have.
There are many stylistic ways to design accessible labels 📍. Here’s a few examples:
5. Avoid clutter!
Before, we’ve talked about the importance of negative space in any scientific poster layout from the point of view of aesthetic. When we consider accessibility, negative space is on your side to ensure your poster is free of clutter so that your readers (regardless of colour blindness) can have an easier time navigating it! 👀
In other words, negative space makes your poster more accessible AND attractive. WIN-WIN! 😉
Tempted to squeeze in one extra graph? Save it for the paper!
Adding one more paragraph about the supplementary data? Save it for the paper!
Citing every single reference? SAVE. IT. FOR. THE. PAPER!
6. Do a quality check by printing it in grayscale
Applied all of the tips above? Great! It’s time to validate.
If you’re not colourblind, print your poster on an A4 sheet in grayscale to emulate the perspective of someone who is. Put your poster on a wall and stare at it intensely for a good minute or two.
Is anything on your poster still feeling ambiguous 🤷♂️? Try getting a second person’s opinion, they might spot something you may have missed!
You can also upload your poster to to the Colour Blindness Simulator (COBLIS) to see what it looks like through someone else’s eyes!
Need a professional design service who can cater for accessibility?
Designing a good poster, especially when taking accessibility into account, can take time. And we completely understand that time is often in short supply in research. Trust us, we’ve been there.
That’s why we’re here to help!
Our creative team at Animate Your Science can design an accessible poster that’ll stand out (for all the right reasons) for the next poster session! Here’s what one of our satisfied clients have said about our poster design services:
”I worked with Animate Your Science to create scientific posters for my work and they were super efficient and delivered great quality posters. Highly recommended!"
Monique Marques, Vitafluence.ai
Presented at the International Society for Autism Research (INSAR) Annual Meeting 2022
Get in touch with us and we’ll be sure to have a creative solution just for you! 😉
Dr Juan Miguel Balbin
Dr Khatora Opperman
Dr Tullio Rossi