If you wanted to describe locations on a sample on a microscope slide, you could create a coordinate system on the slide. But it would be confusing because to get to a point further to the right on the slide, you would have to move the slide to the left. That is, going right means leftward movement. There is a relativity here that reverses everything. Thus there are reasons to orient the coordinate system in different ways or create multiple coordinate systems.
Do people ever use coordinates on microscope slides? Is there a clean way of managing this backwardness? Is there a standard terminology or other convention for this situation?
I’m not sure I understand your question - are you putting the coordinate grid on the slide itself? If so, you get used to the reversed direction pretty quickly. If someone says what you are looking for is to the right, you don’t think “Ok, I have to move the slide to the left, so I turn the stage control knob counterclockwise,” you just do it.
If you want to just come back to the same spot, there is usually a vernier gauge thingy on the stage, so you just bring it back to the same position without looking at the slide itself.
This is how optical and touch probe equipment works. You get used to using the machine and it’s not a problem. Different machines can be the opposite of each other, because it’s not a standard set in stone. Think about combing your hair while watching yourself in the mirror. You do this without thinking about it. Think about it and you often do the opposite of what you want to.