Why is it that narrow black and white lines, make my eyes dazzle?
Link to Journal Article – this has each of the 25 images, in large size, at its end.
This question has haunted me for years. I remember as a young child, over 60 years ago, being intrigued, nauseous and almost fainting as I sat in church behind a lady with a harshly contrasting black and white striped dress. Google does not seem to be able to provide a satisfactory answer. The closest I can get has something to do with the positioning of the black/white light receptors in the retina – the ones that let us see in monochrome in the moonlight at night, colour completely washed out. The point at which I am able to discriminate between the lines somehow seems to be linked to the zone of “en-dazzlement”.
I decided to experiment, using Photoshop as the creative engine.
First I created a high resolution set of black and white bands (20cms square, bands 1cm wide, resolution at 600dpi). Did I experience dazzle? No. I narrowed the creation, step by step, and dazzle began to occur as the band width approached the 1mm width size. Ahar!
Creating the next set of narrow bands took much longer: each strip 1mm wide, alternating white with black, until the 20cm square was covered. Did this dazzle? Most definitely, yes! The dazzle became more exciting as I squeezed and nudged using Photoshop’s edit facility, and my curiosity and excitement grew. This was going to be a good day!
A few of the more exciting results I have uploaded to RedBubble (links below) then my curiosity began its characteristic side-move – would a similar effect happen if the lines changed to tiny squares or circles? I proceeded to evolve the 1mm lines first into 1mm squares, by placing a copy of the white bands rotated 90 degrees over the original. Once this had been saved, I proceeded to turn the squares into circles of varying diameters, some white on black, and others black on white. Concerned that the circles were all in parallel lines, I rotated the square 45 degrees, and using copy-paste filled in the triangular gaps at each corner. Each circle was now adjacent to a gap between circles in the adjacent row. This then was to be a base image for further explorations, into the en-dazzlement phenomenon.
So now I had four base images to manipulate: 01 Prison Bars, 02 Square Peg Swarm Searching for Round Holes, 03 Multiple Bee Stings and 04 Machine Gun Target (in order: vertical 1mm black then white bars, 1mm square black on white background, 1mm diameter black circles on white background, 1.5mm diameter white circles diagonally offset on black background with square diamond in black).
“Prison Bars” Images
05 Motor Bike Approaching at Speed – “Prison Bars” straight bars radiating out from the centre demonstrate brilliantly the relationship between the dazzle effect and width of bands, because the bands are widest at the perimeter narrowing to points at the centre. Various optical illusory effects become increasingly prevalent as one’s eye approaches the centre. Its companion, 06 Quadribulge, was created from “Motor Bike Approaching at Speed”, spherized once in each of four quarters, introducing a definitive 3D effect superimposed on dazzlement.
07 Penta Zebalon – a kaleidoscope of five wings created from a modified “Prison Bars”. The swelling shapes take on a 3D effect rather than dazzlement, though as they narrow towards the perimeter of the overall square frame, some dazzle becomes apparent.
08 Rites of Spring is a whimsical play with a pattern mask laid over “Prison Bars”. Dazzlement is virtually absent, and the black lines are gently etched with diagonal white scratches within the image of a young ballet dancer. Its companion image is 09 But a Hint of Spring where line width is distorted within the pattern shield, the edges of the ballet dancer are quite sharp, so one’s brain has to accept sudden changes in the degree of dazzlement. Its subtlety makes an interesting interplay within the focus of this study of brain dazzlementation.
10 Uni Blob demonstrates the result of repeated, superimposed spherize distortions to “Prison Bars”, until it appears to rise almost vertically from the page. Its companion, 11 Fish Eyes demonstrates what happens when Spherize is applied to “Prison Bars” in negative, producing wide lines at the sides progressively narrowing towards the centre. Dazzle increases as the line width reduces, reaching its maximum at the centre.
12 Venezia Awareness explores the subtle interaction between a silhouette image of the familiar shaped prow of a Venetian gondola and “Prison Bars”. By playing with sharpness and blur within the silhouette, I demonstrate that dazzlement is increased/differentiated under blur conditions compared with sharp conditions. I find it hard to decide which is the most dazzling, because the quality of the dazzle is different, although quite apparent in each case.
13 Zebra Rump was created by imposing single spherize distortions progressively and concentrically, at regularly increasing diameters from the centre towards the circumference to “Prison Bars”. Its companion 14 Burp Emerging was created almost identically, but this time working from the circumference towards the centre.
15 Zebra Squeeze was created by applying the squeeze distortion effect to “Prison Bars”, then rotating 90 degrees. Dazzlation may be compared easily where the wide and narrow bars lie close to one another – dazzle increases as the width of the bars reduce.
16 Eye of the Cyclone, created from “Prison Bars”, powerfully demonstrates when dazzle becomes movement. Many people, to whom I showed this, complain of a sense of imbalance affecting their equilibrium, saying that the page is moving. Of course it is not, but my theory is that this effect is generated by the counterpoised dazzle from varying line width and the sweeping curves of the cyclonic movement.
“Multiple Bee Stings” Images
17 Golf Ball Dreaming was created from “Multiple Bee Stings”, and a sequence of concentric spherize distortions first full size positive repeated a number of times to accentuate the depth, then two reducing negative distortions, finally with a central positive distortion repeated until the golf ball in the centre became clearly defined. The outer ‘flat’ undistorted surface was blurred to background- separate it from the globe. This was, of course, the inspiration for the next creation, 18 Golfer, in which a large golf ball-like spherize distortion was placed beside the black silhouette of a stylized golf player, who was given a narrow white border outline to achieve separation from the unmodified “Multiple Bee Stings” background. Dazzlement is interesting here, as the golf ball, with its large black circles, achieves a dazzle one would anticipate to be absent, by virtue of its blur. The whole topic of dazzlement is clearly not a simple one!
“Machine Gun Target” Images
19 Lazy Daze – “Machine Gun Target” with central twist – white circles were distorted producing a twisting dazzle effect.
20 Quadriphonic Sonic Boom – created from “Machine Gun Target”, with a series of concentric spherize distortions, demonstrates well the relationship between the size of elements and the amount of dazzlement that results. Its companion, 21 Eye of the Cyclopes was created by reversing some of the spherize distortions near the centre, producing a flattening effect.
22 Coordinating Poles, 23 Heart-Felt Desire A Gentle Kiss and 25 Eye to Eye in Utero, all began life as the “Machine Gun Target” image, with the distortion effect “Polar Coordinates” applied once, three times, and then many times. My interest in dazzlement was laid aside, briefly, as intrigue with what was happening took over. Polar Coordinates is a most unusual distortion effect, and one that I plan to explore more deeply in the future.
I warmly invite others to repeat and extend these experiments – I would be delighted to hear from you!