: How to visualise two-dimensional scientific data-points in a chart... in grayscale? I am not sure whether this is the correct site for this question. The model comes from Physics, the data comes

@Harper654

This is not a trivial problem; I am only going to give some general suggestions. My graphics are conceptional, would need some elegantifying to be optimal.

First: kudos for making the mesh in the background light-light grey. People often overdo that.


Do not underestimate the use of a few different diagrams to
demonstrate the same data! When people drill down into information
visualisations, you cannot be entirely sure about exactly what they
are looking for, so doing two-three might well be the best solution.


Colour

Of course; colour is in many instances the easiest way, I am going to play with some different solutions. First, your colours are not really high-contrast, and the blues and greens are particularly similar. I found nine high-contrast colours by using ColorBrewer, a tool particularly developed for maps, and I selected the print-friendly option. Cartographers have struggled with this for centuries. The colours might not be very pretty, but that is not really the point:



This would give you a graph roughly around this:



I would also suggest that adding an extra legend, at the end of your graphs. It makes it easier to remember the placement and have the added effect of showing where the graphs end, and putting the "name" of each graph closer to context, and how they cross each other at the end (how they merge/group, and which ones goes up and down at the end. If this is of interest). Do keep the "original" legend too, preferably somewhere to the left. Again, a subtle help in mental mapping (please do not follow my example in the box-legend, as the colours there are not really in a sensible order).



So. This is the overview of the data. What to do with the digging-down into details? I am a fan of small multiples. We are pattern-finding machines, and only need a little help. I would put the "big" graph in the beginning of the relevant document, and then I would repeat the shape with the relevant data; with comments. Something like this, perhaps:



An example of use of small multiples, are Pathline:


...a visualization tool for comparative functional genomics that supports
analysis of three types of biological data at once.




Scince you are concerned - and rightly so - about the truthfulness of the graph-lines in what is basically a scatterplot, you could tone the lines down, to just suggest. For example by making each datapoint a "train-stations" or bulls-eyes. thus:



Greyscale

This will also work in grayscale. You can of course combine this with Scotts suggestions of different shapes.



Scott has covered the basic idea of grayscale, and you can take that further to also use the small multiples. He has covered the general idea: you have shape, direction, density, stroke, contrast and placement.

What to do when the strokes go madly with overlap, as per your images 2, 4, 5?

For example this, colour and greyscale:





To conclude. The most important rule is to not 3D-ify two-dimensional data (I will come and poop in your mailbox).

What do I think you should do? I think you should go for colour, but use it wisely. I think you should make - say - two different representations, and then keep using small multiples around the text.

It is also worth mentioning that very smart people have struggled, and found solutions to, complex visualisations. Here you will find a list of digital tools that might well be useful. Plot in your data; generate numerous versions.

Let me know if I have forgotten to address something.

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@Caterina889

When working with items which all must be 100% and the same color I look at the things which make the items distinctive:


size (including widths of strokes)
style (dashes, dots, etc)
fill (hollow, solid, patterns)
shape


Then it's a matter of how I can adjust these four settings to create enough distinction between items so they are visibly different.



The varying of dashes on the paths will do well to create distinction between those items. It could probably be refined a bit more than it it above. However, that seems like a fruitful path to take for those items.

The indicators are still unclear. I played with using some filled and some hollow but nothing was allowing for clear distinction between the square, diamond, and triangle. They are all too similar in shape. So.... I eliminated some shapes in favor of varying fills.



I removed the triangles because they were the most confusing shape and easily misread. Replaced them with a filled circle. I also altered the diamonds so they are filled rather than hollow.

I end up with 4 distinctive shapes:
- hollow square
- hollow circle
- filled diamond
- filled circle

There's still a bit of confusion between the diamond and filled circle.. So, I start thinking of what shape would work and be less like the others. Hexagon - too similar to circle, Triangle - as stated, too similar to square and at a small size, not clearly distinctive from circle. A star perhaps? Yes, but perhaps too decorative.

Eventually I settled on the most minimal route, a filled square.



So, I end up with 4 distinctive shapes which are clearly identifiable and 4 distinctive paths which are clearly separate.

The varying plots of the other image is a challenge. Altering the path dashes would still separate them from each other well. However, the overlapping of the plots may present an issue. It would be difficult to plot multiple paths on the same point and not have them look like one path, especially without color. In this case, if possible, I may explore tints as well as dashes. Making each plot a percentage of black. Therefore when they overlap, the black becomes solid where dashes overlap. This may allow some visual distinction for the overlapping plats. To be honest, I would need to explore this further (if tinting is an option) before I'd know for certain.

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