This illusion was new to me. Does whichever dot you look at turn more purple?

Pretty neat how clearly this lets you see the reduced sensitivity to blue light in the very centre of your vision.

https://www.schulz-hildebrandt.com/9-purple-dots-illusion/

https://arxiv.org/abs/2509.11582

@Danpiker interestingly it works better for me on the smaller thumbnail than on the full version of the image