09 May 2015

"Elements of visual perception"

My quilt for the Elements challenge started with wanting to use benday dots, and is morphing into ... I don't know what. 

After painting a sample of dots, I tried layering and quilting them. These represent colour perception, which physiologically happens in the cones, and their signal gets passed along via ganglions and photoreceptor opsin proteins and suchlike, to the brain - read about it here, it's quite complicated, but clearly explained. 

You can just about see where the organza covers the cotton, leaving the central part clear. As soon as the layering made for a complicated pattern, it makes for complications with quilting in short rows [to resemble the rods in the eye, for light/dark perception] - it gets all jumbled. It IS all jumbled! Too many ideas bouncing around next to each other, including this one for getting in the light/dark distinction -
Used at different scales, these gradients of dots would also convey the idea of perception of whether an object is near or far - though that is also done by other cues, such as position/overlapping.

A little research on colour perception came up with a surprise - the cones in the eye are set up to register three colours all right: red, blue, and green (called L, S, and M cones - each has a signal so that yellow results from the lack of a blue signal -
Neural signals sent to the brain (via)

These "cone mosaics" show the retina around the fovea (the area responsible
for sharp central vision) in a normal eye and a colourblind one (via)
Arrangement of short-, middle- and long-wavelength-sensitive
cones in human foveal mosaics
Zebrafish retina (via)
Zebrafish cone photoreceptor mosaic (via)
Rainbow trout retina from various areas of the retina (via)
Lots of dots, and interesting patterns ... and it's fascinating to see what research is going on in visual perception.

The human eye has 5 million cones and 100 million rods - and there are 200 times more cones in the fovea than the rest of the eye.
Density of rods and cones (via)
Zebrafish retinas are similar to human, but come in more exciting colours - or rather, images of them do -
Three of the four cone types in the zebrafish retina - the cones are patterned like
an elaborate checkerboard, with mirror-image cone-cone
neighbor-relationships reiterated across the eye
In and of themselves these cone mosaic patterns wouldn't make an interesting Elements quilt. Something more is needed, and it has to make sense. I'm quite tempted by the idea of combining the microcosm of the cell structure, visualised with microscopes, with the astronomical macrocosm, visualised by telescopes -
Cone nebula (via)
What are stars but millions of little dots of light, impinging on millions of cells in an eye?

No comments: