Tuesday 19 June 2012

The Greyline Project: the line of twilight


'German Romanticism: a heightened sensitivity to the natural world...a passion for the indeterminate, the obscure, the faraway; a desire that the self be lost in nature's various infinities.'

                                                           Joseph Leo Koerner, Casper David Friedrich

Joan Edlis explores the gravitational relationship between the sun and the earth with a series of drawings, diagrams, objects and sound installations. In her new show, The Line Of Twilight, the works exude a delicate peacefulness.


Edlis is preoccupied with the fundamentals of the universe: the way the earth turns within the energy outpourings of the sun and its resulting effect on the planet; waveforms in every conceivable realization, either directly as natural phenomena or indirectly as diagrammatic interpretations of those waveforms.
The word ‘Grey Line’ is a ham radio term for a characteristic of the earth’s atmosphere combined with the planet’s tilt relative to the sun. For Britain, during just a few weeks in January, radio operators here can communicate with those in New Zealand, almost 19,000 km away. The line of twilight encircling the globe propagates radio wave differently from the rest of the atmosphere. Radio operators exploit this phenomenon, their signals travel along this line, reaching to far distances. These are all aspects that Joan investigates in this show.
Edlis explores ordinary commonplace events to do with astronomy, ham radios, solar observations, then documents her investigations and discoveries, questioning why are the summer days are so long? Why is the longest day of the year not when the sun rises earliest and sets latest? What is a neap tide, an ebb tide, a spring tide?

Simon Wilson, writing about one of her works:
‘Grey Line Half-Sphere' 2012, is made from pulped egg cartons, cotton wool, the watercolours Payne’s Gray and Cobalt Blue Hue, found scrap roofing lead, and string from a postal supplies store in Vienna. This list highlights Joan Edlis’s extraordinarily sensitive and inventive approach to materials, which places her in that materials-led tradition of three-dimensional practice which has been central to modernism since Picasso’s Cubist constructions and Brancusi’s doctrine of ‘truth to materials’. She also possesses a powerful sense of the relations of elements in space. The result here is a compelling  harmony of simple form, colour, texture and space that gives immediate satisfaction. 

But on further reflection one wonders why that tilt of the hemisphere, and then realises that the coil of lead is there to create it. And the hemisphere is just that – half the Earth - and the angle of tilt is that of the Earth in relation to the sun. Grey Line Half-Sphere thus takes its place in the series of meditations on that most fundamental fact of human existence, our relationship to the sun, that makes up this exhibition.’

 E
xhibited works

Cur nĂ  dtonn
Gaelic for ‘seafoam’ where small bits of detritus float on the sea‘s surface, sometimes trapping bubbles, and bob up and down in one place, riding the waves.
 
Daylength 51˚N 0.5˚W (London) - Solstice/Equinox/Solstice (gas jars)
Three different liquids – transparent, dusky and opaque – proportioned according to day length in London for different seasons.  The dusky layer slowly sinks into the layer of darkness over a period of days.
Colours of Dusk
Household liquids sealed with wax in all the shades of dusk.
Vermilion Tone Time
Watch crystals containing Vermilion tone gouache, positioned on a diagram of the sun’s ecliptic arc, the path the sun takes throughout the day relative to the celestial sphere. In summer the arc is very high, sweeping across the breadth of the sky, and in winter it is much shallower, appearing to rise and set across a much narrower arc.

Twilight 50˚08' 30' N 29 May 2012 (Cambridgeshire)

Twilight, measured from 20.48 to 22.20 in lux (luminosity) then plotted as a graph, defines the state of darkness over 21 aquatints, also measured in lux. Light level readings were recorded at a site in Cambridgeshire having minimal night time light pollution, as seen in the three images of the night sky with moon.
Genuine Vermilion Disc
The dry pigment Vermilion derives from sulphur and mercury (mercuric sulphide). Toxic and prone to turning black in sunlight this colour is also known as Cinnabar Vermilion, Scarlet Vermilion and Chinese Vermilion.
The Grey Line (sphere)
The equator is not simply a cultural construct but the fastest moving point on the surface of the earth. Geo-centrically the equator and the poles travel elliptically within the celestial plane; helio-centrically the poles are tilted at an angle of 23.4˚ to the ecliptic plane. Positioned to receive morning sun, the lens will focus sunlight onto the red disc throughout the duration of the exhibition, resulting in a dark record of light.
The Grey Line (half-sphere)
The earth turns within the outpourings of the sun’s radiant energy. The tangent point of the globe where sunlight just skims the surface of the earth is the band of twilight, also know as the Sunset Terminator.
Curve of Darkness 51˚N 0.5˚W (London) 19 June 2012
The Grey Line appears as an asymmetric curve on this Winkel Triple map projection, devised to reduce the distortion of landmasses towards the Polar Regions. Certain ham radio frequencies reflecting within this line of continually diminishing solar energy, using it like a path to reach distant parts of the globe. The shape of the curve constantly alters according to season.
Earth Sound Receiver
Lightning strikes generate Extra Low Frequency (ELF) sub-radio signals, which bounce within and travel along the Grey Line’s path.  A horn amplifies these frequencies into audible sound from lightning as distant as 1000 km.
Shade and Shadow (slideshow)
Shade is the result of the lack of direct light falling on a surface; shadow is the result of something blocking direct light, or interposing between a light source and a surface.

Shade assists the eye/brain to recognize and define three dimensional shape and form; shadows can do the opposite by obscuring and blurring the definition of what we perceive. Conversely, the  absence/diminution of light often helps the eye to see more clearly, stimulating only rods, which outnumber cones by 20 times (still from slide show).
Circling tide (wave) (video/four speakers)
Gravitational attraction between the Earth and Lunar masses generates the ocean or planetary bulge which drives the tides. The shingle on this particular stretch of Irish coast is oddly angled to the direction of the tide - thus the crash of waves pans dramatically.