The Negative AfterImage

A surreal experience of the retinal projection

Sujatha Ratnala
5 min readApr 17, 2020

It was my third optical illusion this week. A college friend had forwarded this image in the whatsapp group. After vaguely viewing for 10 seconds, I almost freaked out what I saw. It seemed so surreal like a fiction movie. Was I projecting with my head?

Look at this image if you have not done it before..

I repeated it a few times to check it was no illusion.. It worked for a few minutes and gradually disappearing.. A blink would make it disappear.. It was great with light on and kind of hazy with lights off..

Everything was projected in detail.. And zoomed on the wall like a projector.. The dark mobile silohette.. The square picture.. The lady with her hair open and her eyes.. The colours of the hair and the face seemed to be reversed.

I am one of those kinds who have an absolutely non photographic memory.. What was this miracle that seemed so irrationally rational?

I made a quick assesment.. It is definitely something to do with the capture pipeline of the eye and not the recording pipeline involving the mind and memory.. It seemed like a capacitor discharging the stored colours and overlaying it with the vanilla capture of the wall. May be it works with special colour combination silhouettes.

My intuition was not too off. Another friend shared a wiki link. This phenomenon was called as Negative AfterImage.

A little bit into the anatomy of the Retina.. Picture credit Dr Kiran Kumar who is a Pathology Professor and a fellow whatsapp victim to the optical illusion.

Like the LCD and plasma display, the retina of the eye captures the image. It has layers of complex circuitry. The light and colours causes photo excitation and a sensing of colours and intensity.

Through the network of nerves, both the eyes are connected to the rear portion of the brain for visual processing..

In the case of Negative AfterImage.. due to the saturation of the colours in the image, it seems the colour pigments of the retina get depleted and start emitting the reverse colour for some time.. And this is overlayed on top of what is freshly captured..

The scaled up zoomed size of image is perhaps due to the proximity of the mobile to the eye.. the mobile took big chunk of viewing area.. While viewing the distant wall, it seems to be zoomed.. Mystery of the NegativeImage kind of solved.

The negative afterimage seemed to be causing a headache.. Thankfully the real world is not starving for colours.. That might explain why we get fatigue with books and stationary screens. The solution is to colour balance once in a while looking far off.. The vastness of the blue of the sky and the green of the leaves.. the brown of the trees and the earth are so pleasing to the eyes..

Medium as a blogging platform is so appealing due to the fantastic harmony in the limited options it provides.

Thankfully, the neo digital world is moving towards softer colour palettes. The Verde palette for instance has the colours combinations inspired by nature and can be seen by the colour blind.

People off late have been complaining of headaches and fatigue with lockdowns, work from home and constant zoom meetings. Makes me wonder if the future of display technologies and video conferencing have better harmony in the color elements and defocus unnecessary details. Every time I turn the iPhone screen off, the black display abruptly hurts the vision like a black hole. Probably something like this..

Almost a year later I was looking for ideas to declutter and hide the wires emanating from all the accumulated gadgets in my living room. And look at what I find? A pleasant looking basket.. (I am not recommending this.. There can be thermal issues).

This picture also reminded me of the aesthetics of Apple products and their choice of light colours which are soft on the eyes.

hydrangeatreehouse.com

The senses filter, decimate and illumine the world for us. In a sense, the plurality of the outward worlds that we all perceive only exists within us.

There is earth, sky, heaven and infinity..
There is fire, sun, moon and illumination..
There is eye, ear, mind and then establisment of the world..

-Chandogya Upanishad

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Sujatha Ratnala

I write.. I weave.. I walk.. कवयामि.. वयामि.. यामि.. Musings on Patterns, Science, Linguistics, Sanskrit et al..