Inner Eye

TillyvanI HAVEN’T USED my smallest sketchbook, the little Moleskin, for almost two months but as I tie up one loose end after another I’m getting into drawing mood again.

Tilly has also appeared in my notebook. She pops up all over the place.
Tilly has also appeared in my notebook. She pops up all over the place.

OCT Scan

gableI had my first OCT scan at the opticians this morning. The infra-red scan mapped out a small area at the back of my eye and rendered it in 3D, reminding me of the 3D modelling I’ve experimented with in programs likeĀ Bryce and Vue.

She's a restless sitter.
She’s a restless sitter.

A shallow crater is where the cone cells for daylight vision are concentrated. These are particularly sensitive to movement but they’re useless in the dark so as the iris opens to let in more light a wider spread of rod cells takes over, with the crater of cone cells becoming a bit of a blind spot.

This explains why when observing a faint object in the night sky, such at the Andromeda Galaxy you have to do that trick of looking slightly to one side of it. It’s too faint to register on your array of cone cells.

blind spot

My true blind spot, the spot where blood vessels and nerves enter the eye, looks less like a crater and more like a corrie surrounded by glaciated peaks.

 

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