I sincerely apologise for the duplicate question. I'm not sure how to add to the discussion on the original, and I don't have enough reputation to leave comments.
Here is the original question: How to choose the right color shades/tints for branding?
The favourite answer says that tints and shades maintain the same hue value as the base colour. The problem is Material Design tints and shades don't do that, and I would take a guess that they are using the HSL model for their S/B levels:
There is quite a big difference and the Material Design colors have a much more pleasant range.
I want to gain a deeper understanding of just exactly the process they have to get these results? I presume they must have some kind of tooling to achieve the correct perceived color.