Two circles with "exponential decay" coloring, and alpha < 1, have trouble with color mixing on overlaps

Hi all,

In order to get circles such that their coloring is radially symmetric, with
center being the darkest, and exponential decay in color as one moves
farther away from the center along the radius, I used imshow with clip_path
using Circle patches.

Here's a toy script that overlaps two such circles:

As you can see if you run the script (or, if you follow this link: ), even
though the alpha is set at 0.5, there doesn't seem to be proper "color
mixing" occurring (we should see a result that is symmetric along the

Why is that, and what could I do to fix this issue?

Kind regards,


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