Talk:Color vision

The second (violet) maximum of the sensitivity of the red cones

(I recently started this topic, but after that all the talks from 2006 to 2019 ended by my message were automatically archived.)

The four pigments in a bird's cone cells (in this example, estrildid finches) extend the range of color vision into the ultraviolet.

In some sites (e.g. https://midimagic.sgc-hosting.com/huvision.htm) I see charts of light sensitivity curves looking different. Namely, the curve of the red-sensitive cones has a second (tiny) peak in the violet range. It is said:

The erythropsin in the red-sensitive cones is sensitive to two ranges of wavelengths. The major range is between 500 nm and 760 nm, peaking at 600 nm. This includes green, yellow, orange, and red light. The minor range is between 380 nm and 450 nm, peaking at 420 nm. This includes violet and some blue. The minor range is what makes the hues appear to form a circle instead of a straight line.

There is no reference to scientific papers neither numerical tables in https://midimagic.sgc-hosting.com/huvision.htm. I have not found any evidence of that in Wikipedia except that of a bird's cone cells rather than human's (see the chart):

Is this a fake science or an obsolete disproved theory? If not, could anybody find a reference to an authoritative source?Ufim (talk) 08:37, 28 April 2019 (UTC)