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Your genes for generating blue cones are not located on the X or Y chromosome. That means both men and women can end up with too many or not enough. I have a severe shortage of blue cones ~ and a surplus of red ~ which takes me right outside the norm for modern southern latitude humans, but probably right on the mark for all Arctic peoples ~ whether white folks or oriental types!

When I had cataract surgery some years back my night vision clicked on. That's a known phenomenon but not frequently experienced by most (99%) of people but well understood in the Far North.

As I gradually returned to normal activities I found I had to wear sunglasses to drive at night due to the incredibly bright lights along the roads and in residential districts.

The same thing happened a couple of years ago when I had far more serious surgery in one eye ~ the old night visioned kicked in 24/7 for several months. The medication administered in one eye also migrated over to the other eye through the capillaries and was I ever a mess.

Night vision flared up for a couple of days in early November this year, but it's quieted down now.

Since I know and understand these phenomena in my eyes it doesn't bother me all that much that I frequently see some really strange stuff ~

Note: if you are short blue cones you will be blue/green blind ~ simply unable to differentiate the two colors AND, worse, yellow will appear as white ~ in the center of your field of vision. You will see colors normally in the outer periphery because the rods overlap blue cones in frequency sensitivity ~ but the center will be blue blind. However, if you have plenty of rods spread evenly through the retina, and not just outside the central area, you will have fairly normal color vision most of the time EXCEPT when you are in an area lit by blue light. Then you will see everything in a sort of surreal color blend with too much white, not enough blue, and missing yellow ~ sometimes red will look black just like red/green blindness.

That's about 1/10 of 1% of the population ~ so most optometrists have never encountered it ~ but there's a term for it!

I had a first grade teacher who used to inflict severe distress on me for not differentiating between NAVY BLUE and BLACK. They are, of course, the same color! if she were still alive, knowing what i know now i'd sue the school district for torture of a young chil'.