I ran into this slide (fragment) presented on an online course site the other day (I now digest tons of these to refresh my coding skills):

It shows a common problem in PowerPoint: you picked a nice theme colour (deep purple in this case) and you need variants of it. (This presenter figured out that too many colours makes your slide deck cluttered, hence SlideMagic only allows one :-) ).

The default model to make colour changes is to modify its brightness. It almost always work to make things darker, the other way around though can create a problem for very saturated colours. You don’t notice the saturation level at dark levels, but on brighter variants, that elegant purple becomes cute/bright pink.

The solution: change colour saturation as well as brightness. This post on my blog from 10 years ago (what?) describes it:

PowerPoint 2010 gives you the option of a spectrum of different shades of the same color. This is great to design charts with a consistent color scheme.

However, if your template contains colors that are highly saturated, the suggested lighter shades of your color will be too bright to use as neutral color nuances. Here is how you can fix it. (Click on the image for a larger picture.).

Create a new base color by reducing the saturation (in laymen's speak: make it more grey). Open the color in your color template (format shape/fill/solid fill/color/more colors)Switch the color model from RGB (red, green, blue) to HSL (hue, saturation, luminance).Reduce the (S)aturation value, while keeping all other variables the same.Use a lighter shade of this new base color instead and save this as a new color in your color template.

A (by now blurry) image with additional clarification:

A simpler approach:iInstead of changing the RGB values of your colour, simply add transparency to the dark colour. This works great on white backgrounds, but will create problems on coloured surfaces.

Another approach building on this:

• Create a shape with the dark colour over a white background

• Increase the transparency until you reach the desired level of “brightness”

• Hover over the box with a colour picker and add the colour you just picked to your slide colour palette.

Photo by Denise Johnson on Unsplash