Rect Transform pos values give different 'spacing' in UI?

Unity Engine
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1

So I’m having trouble understanding what is happening. I have a button that is anchored to the bottom left of a panel, and the button’s pivot point is also set to the bottom left. My problem is that when I put the PosX and PosY both to 50, the button is not equally spaced in both axis.
9900003--1429884--button.png
9900003--1429887--rect.png

Why does this happen? Am I missing a setting on the canvas or the camera, maybe? Or am I just not understanding something?

2

You probably need to set the pivot values to reflect the exact positioning you want to apply. If you want the button’s bottom left corner to be equidistant from the bottom left corner of the container you probably want the pivot to be (0, 0).