Thursday 4 March 2010

Sisyphus

Photography can involve much repetition, particularly when practised without additional lighting. When the thing being photographed changes all the time, and even vanishes into itself, repetition becomes the subject. This is the case with the pictures I'm making from small waterfalls, dams in a brook built from stones and gravel.


Out of six built last year, only one survives (no.2, shown in the full moon the other night). While I would be lying if I said that this was always the intent, I realised two things as I began to build them. The first, an absolute principle when dealing with water, is that you can't stop it completely, only make easier for the water to go a particular way - through as much as over. The second was that, when the waters rose in winter, the dams would, most likely, be washed away. 


So I was prepared for the disappearance of what I had built, helped it along when the rains came by opening the biggest. As soon as the water found its new channel, it ripped the surrounding rocks away.


Rather than feeling a sense of disappointment, I found myself with the prospect of sisyphean pleasure. Roll that stone!


I began rebuilding a few days ago. This year, I will try to stop at 4 dams; if they get too close together, the waters rise all the way back to the previous dam, reducing the height of the fall and thus the effect of the whole. Patience is needed to do all this: it's tempting to force the rocks into place while the flow is heavy to create instant effect. They never last if you try that. It has to be done in stages.


The first layer has to be firmly wedged, but easily overflowed. That way, it quickly builds a ramp behind from all the debris (mud, sand, shale, etc.) which will form the base of the dam as it is built back and up. This is the only point at which I do attempt to make all the water go over. It's easier to do all this when rebuilding. The side piles, (shown here at no.4) crucial to protecting the bank from unnecessary erosion, are still there from last year. All that needs to be done is to re-connect them across the middle.


That's where the water will be encouraged to go, funnelled in to a narrow space so that the pressure from behind will force it over and through, producing the spouts and sprays I want for the photographs.


(You can see these over at the website.)


Looking at the water as subject, I've started to realise a few things about why it looks the way it does. When it churns, why does it look white, for instance?  Particularly in direct sunlight, the photographs show the reason clearly. Each droplet that breaks free has a property I remember from school physics - total internal reflection - and those reflections, pointing in every direction, are bound to pick up on the light source - the moon, the sky, the sun. 


Here you can see the water breaking over a rock (click for a bigger version): to the right, a smooth body of water gently reflects the light from its cohesive surface; to the left, it is impeded by the rough edge, and breaks into streams of droplets, each with its own internal reflections, all joining together to give that white-water-look. It's another form of fractals, those repeated patterns which lie at the root of so much natural beauty.