Light Painting with a Harmonograph - Part 3
21 Jan 2022 9:30AM
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Part 3 – Trying to Transition from Technology to ‘Art’??
‘Blue Burn’
Once I could exert a reasonable degree of control on the machine, I wanted to try other things, such as dual and multicolour captures using modified RGB LEDs and harder cropping, maybe saying something more than ‘great pattern’.
Around the time of the US election, I was experimenting with red-blue switching, trying to render an entwined form, a forlorn dream of the Republicans and Democrats maybe working harmoniously together:
‘Political Harmony’
More than a year on, it is still a dream, and a remote dream in the UK too! I used a Raspberry Pi micro-computer to switch colour, and control timing for the switching. I could also control the intensity of the LEDs. The RGB LEDs themselves are very low cost, so I could afford to experiment. I bought a length of RGB LED tape for about £10/ metre, so plenty of LEDs to use. Single RGB LEDs come with the dome shaped plastic encapsulant, so to get these ‘pixel sharp’ I had to polish back the dome and then apply pin holes in the Aluminium tape. With the other type, I just had to apply the pinholes, although soldering to the surface mount LED chips was a bit of a challenge! In both cases it needs a bit of trial and error, as the individual emitters are very close together. Programming the Raspberry Pi was very straightforward - follow instructions on the Pi org website
here or ask a friendly neighbourhood student who has learnt to code in school! It is good fun and intuitive. The patterns are best when the switching is synchronous or near synchronous with the platform movement, otherwise the colour can quickly get mixed up and distracting.
The RGB LEDS can produce all the intermediate colours by switching two on at the same time. This led me to work on the Rainbow motif, celebrating diversity and our star health providers throughout the Pandemic in the UK.
‘Folding the Rainbow’
I think these are fine, harmonious patterns, reasonably artistic. With further work, the results could say something quite different. In the composite below I was trying to represent the year 2020, starting with a bit of a stir, and ending nearer chaos. The spiral shapes were achieved by switching the LEDs initially slightly slow with respect to the upper platform, then decreasing the delay slightly on each cycle (only three or four lines of code!)…so the pattern slowly synchronises and becomes stationary, then keeps speeding up into the ever tightening spiral. The first image has no motion on the lower platform, then this increases from image to image. The two platforms are not tuned together, making the pattern chaotic.
‘Going Stir Crazy’
Adding the colours showed me I could move further down the road of abstraction, leaving ‘off’ periods in the light, separating different colour forms…
‘Enfolded’
I love this one; it is recorded with near Unison tuning, so the decay is slower, resulting in the lines being so close together that the red form is almost solid, enfolding the blue form. The forms are very harmonious, but with some separation, and belong together. It is a method I want to explore in the future, maybe with three or four colours.
Taking the switching further, this triptych is entitled ‘Ribbons and Bows’ and shows the different but related forms that can be produced by fairly subtle changes to the start conditions.
‘Ribbons and Bows’
The machine was only just capable of achieving good patterns with an Octave tuning between the two platforms. To achieve this, I had to have the camera very close to the top of the upper suspension, which increased the friction and made precession much stronger and more difficult to null out. I couldn’t come up with a universal solution to this, so I have to change the configuration to do different things. With Octave tuning, the patterns loose the ‘inversion-rotation’ symmetry that is clear in Unison tuning; the patterns I think become more abstract and ethereal. More in the next part! I hope you are enjoying this – only another two parts to go. Please leave a comment or message me if you have any questions or would like more detail.
