Guidelines for Colour Figures

Published figures appear in colour in the online version of MEC/MER articles at no cost to authors. As these “Colour Online Only” figures have the colour saturation of the original version reduced to zero for print, we recommend authors consider paying for colour printing if their figures and captions do not convey the same information in greyscale as they do in colour.* To help authors create figures which do convey as much information in greyscale as in print, we have compiled the following tips.

Figures that work well in colour online and greyscale in print:

  • Use colours that are clearly distinguishable as different shades of grey when the colour saturation of the original image is reduced to zero.
  • Have figure captions that don’t refer to or rely on colour.

How can you create a figure that is easy to read when converted to greyscale?

  • Use a maximum of three colours. We’ve found it is difficult to tell the difference between more than three shades of grey (whether or not these are used in addition to black and white).
  • Avoid colours that are equally bright/dark. Red and green are easy to tell apart in a colour version, but often look identical once the colour saturation is reduced and only the grey remains. Using yellow, red and blue, however, usually results in three distinct levels of grey, as the yellow is lighter and the blue darker than the red.
  • Consider other ways to tell things apart. Depending on the figure, you may be able to effectively use patterns, shapes, and sizing instead of or in addition to any colours/shades of grey.
  • Remove references to colour from captions. Rather than referring to the figure colours, refer to what they represent. If you’ve used patterns or shapes in addition to colour, you can refer to those elements, as they won’t change when the colours do. There are also many instances where colour makes the figure easier to read, but is not essential. In most of those cases, the caption reads well without referencing colour at all.
  • Use an inset visual legend. By providing the legend in the figure, it will be accurate whether in colour or converted to greyscale. This is important for any visual markers that would require an explanation or specific reference in the figure caption.

*It’s the policy of both Molecular Ecology and Molecular Ecology Resources that authors pay the full cost for any print reproduction of colour artwork. This cost is £150 for the first colour figure and £50 per additional figure (see Final MS Preparation in our <a href=””>Author Guidelines</a> for the necessary form).