This question has perplexed scientist and engineer alike. What exactly is the best way to look at my data? The answer is a resounding "it depends on what you're looking for." To help understand the uses of the different color schemes in FEM Builder, we created this article as a guide.
First, let's look at what color schemes we can choose from in FEM Builder.
The color bars that were implemented fall into three categories; Monochromatic, Dichromatic, and Trichromatic.
Monochromatic schemes are shades of a single color that is blended into white. These are the most basic type of contour coloring and work well for being printed in black a white.
Blues and Reds where designed for basic heat plots (hence why Blues is reversed).
Gray scale was created for black and white printing.
Dichromatic schemes are two colors blended into white in the middle. They can be seen as two Monochromatic schemes that have been put together. These schemes work great on following a particular contour of interest.
Red White and Blue was created to provide the most common Dichromatic scheme.
Trichromatic schemes are quadratic interpolation between three colors (one on each end and one in the center).
RGB Rainbow is the default setting. This is the most common method of visualization.
Viridis and Plasma were developed by MatPlotLib, an open source free ware for plotting and data visualization. These were specifically chosen because of the high amount of research that was done to create optimal general color schemes. To see what went into these schemes check out their presentation at SciPy 2015 on YouTube (https://youtu.be/xAoljeRJ3lU). Or at their website (http://matplotlib.org/2.0.0rc1/users/dflt_style_changes.html).
Next, let's look at why these schemes are needed in the first place. To understand this, we will simple look at a picture of some data.
Because our eyes can't see all colors with the same granularity, the RGB Rainbow scheme hides the information in the middle of the field (the square is there if you look really closely). However, because our eyes are better at seeing slight differences in the red region, we can easily see the square in the center of the domain. In summary, using multiple schemes prevents hidden differences that might have gone unnoticed.
There are other benefits as well. Take this model of a choke point, in which color scheme can the 300 m/s choke point (and the contour following) be easier seen?
There is one last consideration, what will the plot look like printed? Because a large amount of people wish to save some money on color printing, they opt with black and white printing instead. The result?
