Mostrar mensagens com a etiqueta Fotografia e Ciência. Mostrar todas as mensagens
Mostrar mensagens com a etiqueta Fotografia e Ciência. Mostrar todas as mensagens

6.9.08

Pherographia: Drawing by Ants

Timor mortis conturbat me.

In 1844, Talbot defined light as The Pencil of Nature. Inside the camera obscura, the artist’s pencil was being replaced by light and silver. Photography had just born, from the camera and chemistry, and the apparatus was no longer used exclusively for drawing lines on top of projected images. But nature has other pencils and the scientific progress of the last decades opened the gates to new worlds, to artificial and simulated environments based on natural phenomena. Several research fields are advancing and cooperating in order to understand how natural systems behave (and self-organize) and how these lessons may be applied in real-world problems. Ants, for instance, are known for being able to act as a swarm, find food and build rather stable travelling paths; ants draw lines on the environment. In 1994, scientists Dante Chialvo and Mark Millonas presented a swarm model with a dynamic behavior that may be tuned in to a region that lies between chaos and order, were paths/lines emerge in a plain environment. As in nature, ants communicate by pheromone (here, artificial), which they deposit on the environment and tend to follow as long as they detect it. Other researchers followed this line of work, and modified and applied the system to grayscale images, in order to look for alternative means to deal with image processing tasks. However, new ideas arise when looking at the aesthetical and metaphoric potentialities of the pheromone fields created by ants. Like the pencils of camera obscura, ants draw lines along the contours of the image, by laying more pheromone were contrast is higher (thus attracting other ants that will reinforce pheromone in that area). Like light, silver and film development, the process is gradual, starting with a blank pheromone landscape were slowly emerges an image, a sketch of the original picture.
The “fields” in this project were obtained by evolving the swarm on black-and-white negatives found in a flea market. The ants can draw over any image, and an artifact/camera to capture it directly is possible, but this way we recycle old photographs, in a kind of ecology of the image. In addition, the stage is given to those anonymous people whose faces are locked up in photo albums. All photographs are memento mori, Susan Sontag wrote. By recovering and working on these images, we try to provide them with a last breath of life.

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Carlos M. Fernandes, Drawing by Ants

Carlos Miguel Fernandes

17.4.07

Uma Camera Obscura para Formigas

A câmara fotográfica apareceu antes da fotografia e chamava-se camera obscura. Os seus princípios de funcionamento já eram entendidos no tempo de Aristóteles, mas foi a partir do século XVI, quando no pequeno buraco das cameras obscuras originais foi colocada uma lente convexa, que o aparelho se transformou num meio para o registo permanente de imagens. Vermeer e Canaletto são apenas dois exemplos de artistas que utilizaram a camera para a criação de algumas das suas obras. Quando Johann Heinrich Schulze (1687-1744) ainda fazia fotogramas com letras recortadas e coladas em garrafas cheias com cloreto de prata e ácido nítrico, quando a daguerreotipia ainda era um sonho de Niépce (1765-1833), já o apparatus estava mais do que preparado para receber a nova invenção. Mas era para “desenhar por cima” que a camera obscura servia antes da invenção da fotografia (na verdade também foi útil na astronomia, muito antes de Vermeer a utilizar). Vamos agora ver os resultados de um artefacto vagamente semelhante, mas artificial, e concebido para formigas artificiais. Uma camera digital onde as formigas podem desenhar, com feromona, por cima de imagens a preto-e-branco.

Carlos Miguel Fernandes, Shigisoara, Roménia, 2004

Carlos M. Fernandes+Vitorino Ramos, Self-Regulated Swarm Image #1

Carlos Miguel Fernandes, Timisoara, Roménia, 2004

Carlos M. Fernandes+Vitorino Ramos, Self-regulated Swarm#2


Quem estiver interessado na parte científica do projecto, pode consultar os seguintes artigos:

Carlos Fernandes, Vitorino Ramos and Agostinho C. Rosa, Self-Regulated Artificial Ant Colonies on Digital Image Habitats, in Int. Journal of Lateral Computing, IJLC, vol. 2, nº 1, pp. 1-8, ISSN 0973-208X, Dec. 2005.

Vitorino Ramos, Filipe Almeida, Artificial Ant Colonies in Digital Image Habitats - A Mass Behaviour Effect Study on Pattern Recognition, Proceedings of ANTS´2000 - 2nd International Workshop on Ant Algorithms (From Ant Colonies to Artificial Ants), Marco Dorigo, Martin Middendorf & Thomas Stüzle (Eds.), pp. 113-116, Brussels, Belgium, 7-9 Sep. 2000.

Posso adiantar que as formigas em causa têm apenas percepção local, “vêm” só, em determinado instante, o pixel onde estão colocadas e os pixels circundantes. Não há controlo centralizado do enxame. A imagem emerge através da interacção do formigueiro com o ambiente.

Carlos Miguel Fernandes