Monday, 29 November 2010

Parabolic Reflector

Parabola vs. sphere
If cross-sections of a spherical surface and a parabolic surface were made by slicing each surface in half, these would be the shapes you would see:

I've been wanting to make a parabolic reflector for quite some time now.
As I have heard more and more about them, from Marcus Coates using them to record specific birds in trees for his work 'morning call' and Chris Watson amongst various other sound artists mentioning them on several occasions, I thought it would be worth checking out what all the fuss is about.
I managed to find these instrucions of how to make a parabolic reflector on Instuctables. It also gives a dxf. file which is excelent as I could use this for the Laser cutter machine they have here at Bezalel.
There is also a rather good link to youtube on this page, showing a parabolic reflector being used to cook some bread and fry something (not sure what exactly).

And here is a very useful Java tool for anyone who might be wandering about how to calculate the radius of a parabola, according to it's length and therefore find the focal point - Equation of Parabola.

I was originally going to make a concrete parabola, something like what they used on the coast of britain to detect incoming aeroplanes during the war, using a large inflatable exercise ball.
However, after some research I realised that I had made one of the fundamental misconceptions - that a parabolic dish is part of a sphere. It is not. It is part of a paraboloid.

If you slice a cone with a plane that is parallel to a line on the cone through its vertex (such as UV on this figure), the intersection is a parabola. Here is a proof of this fact.

Saturday, 27 November 2010

The Jerusalem Show


During my first couple of weeks in Jerusalem, still sleeping on the floor in the studio of a friends apartment, one evening we went to an event at the The Al-Ma'mal Foundation for Contemporary Art.

Here we saw a fantastic performance by Uriel Barthélémi

Uriel Barthélémi is a composer, drummer and electro-acoustic musician who creates compelling physical and psychological dramas through the intense production of sound. Combining drums and electronics, composition and improvisation, his work captures the very essence of live performance.

Tuesday, 16 November 2010

Radio Free Jaffa

Liberating space through art and action - all.FM:

Along Jerusalem Boulevard the entrance into Jaffa. , Radio Free Jaffa made a radio intervention into all radio transmissions in the proximity.

Radio Free Jaffa offers free space which is much needed in Jaffa, and deals with the current social and political situation in Jaffa by highlighting the housing crises and the evictions of Arab residents from the city.
Radio Free Jaffa walks in Jaffa as a human antenna, broadcasting in close-range. It may not be noticeable, but if your radio starts behaving strangely, you can assume we are in the area.

Monday, 15 November 2010

Radio All Workshop

Israeli Centre for Digital Arts,
Holon, Tel-Aviv

As an introduction to the workshop, Kasia Krakowiak, a polish artist interested in the potential of radio in the wider community showed us this video. It is a story of underground Polish Radio pirates:

'In 1985 a group of astronomers from the University of Torun consturcted their own TV transmission equipment and superimposed Solidarity slogans over official TV broadcasts.'

Another isteresting video which helped to demonstrate what her practice's concerns were, was called the Complaints Choir of Birmingham. The Complaints Choir invites people to complain as much as they want and to sing their complaints out loud together with fellow complainers. The first choir was organised in Birmingham followed by the Complaints Choir of Helsinki and Hamburg. The lyrics were written by the Choir, Music by Mike Hurley. Project by Tellervo Kalleinen and Oliver Kochta-Kalleinen. Produced by Springhill Institute.

Tuesday, 2 November 2010

Hecker: De/Naturalising the Ear-Brain

Chisenhale Gallery - Thursday 18 March 2010

Beshkan! (1991)

Here is a pretty great video that I found on this blog 'Belog' which I discovered through the website of a magazine called Bidoun which is about Art & Culture from the Middle East.

International Artists workshops in Holon

Israeli Centre for Digital Arts

An e-mail was sent out from the school giving details of free workshops which would be happening in Holon, an area just outiside Tel Aviv, so I got in touch and enlisted myself for the following workshops. Very excited about the prospect of learning Pure Data in a bit more depth!

Genderchangers: Remote Intimacy

Friday, November 12, 9:00-13:00 and Sunday, November 14, 9:00-17:00

Kasia Krakowiak & Ronen Eidelman: Radio all.FM

Radio Hacking, Space Liberating

Monday, November 15, 10:00-16:00 and Tuesday, November 16, 10:00-13:00

Frank Barknecht: Introduction to Pure Data

Wednesday and Thursday, November 17-18, 9:00-17:00