LIMINAL – tech sheet (en)

Tech sheet for the LIMINAL installation

Physical characteristics

The ring is made of 2 cm square U-channel aluminum, covered in white acrylic on the open side. It can stand under its own weight, but needs to be balanced with thin metal cables that are attached to the ceiling. Alternatively, it is also possible to attach it to nearby walls. In the case where ceiling or wall attachment is unfeasible, cinema C-stands with sandbags can be considered as a last resort option. The ring is designed to be portable and easily assembled.

Required equipment :

Provided by the artist:

  • An illuminated aluminum ring that can be disassembled into five segments. Each arc is 165 cm long, with a flat segment that rests along the floor (see plan below)
  • A high-quality USB camera on one side of the ring
  • A Windows computer running Derivative TouchDesigner (for short durations only)
  • Various cables and adapters for the camera and ring

Provided by the venue:

  • A HD or better projector; ceiling-mounted is best, short-throw as an alternative
  • A pair of actively amplified speakers
  • A subwoofer
  • A plinth (approx. one-meter cube) used to conceal the computer; it may be used for the projector in the case where a ceiling-mount is not possible
  • Audio cabling (the audio coming out of the computer is the standard 3.5 mm mini jack). Left and right channels are identical
  • An HDMI cable (or equivalent) running from the projector to the computer
  • Optional: a projection screen in the case where a wall projection is not possible (see space requirements below)

All equipment can be provided by the artist, but it would be advisable to source the projector, speakers, subwoofer and plinth locally for both economic and sustainability reasons.

Computer requirements

Here are the minimum tested requirements for the PC :

  • Windows 10 PC running Derivative TouchDesigner 0.99 2018 Commercial
  • nVidia 1070 GPU or better
  • i7-7700 CPU or better
  • 16GB RAM

Shipping requirements

The ring and peripherals (excluding the computer, projectors, speakers and plinth) fit within a 180 cm x 35 cm x 20 cm case. Total weight of these components is under 15 kg. This fits within airlines’ allowances for oversize check-in baggage. The computer is either a Windows laptop (provided on-site by the artist), or a Dell XPS 8920 desktop (approximately 15 kg shipping weight).

Space requirements

In terms of space requirements, refer to the plans below along with these guidelines:

  • A volume that is minimally 4 m long x 3 m wide x 2.5 m high is required
  • Projection : the projection surface can be an adjoining white wall or alternatively a projection screen. Screen size is proportional to venue space. It needs to be at the bare minimum 2.75 meters wide (for a very small space). Bigger is usually better. 4.5 meters wide is good, and projection sizes up to 8 meters wide have been used to great effect. The aspect ratio of the image is nominally 3:1, but can easily be adjusted in software.
  • A ceiling-mounted projector is ideal, alternatively, it can be placed on a plinth – it is important to plan that the onlookers don’t hide the path of the projector
  • The space must be dim enough to use a projector
  • The space must be quiet enough to hear the output of the speakers (including low frequencies)
  • The installation needs to be stabilized by four to six cables attached to the ceiling, or alternatively to the walls. The tension is less than 5 kg. These cables must not come into the path of the projection beam.

Electrical requirements

Electricity requirements are minimal and flexible – 100-240v, 50-60Hz, 15 amp circuit (about 600 watts maximum, excluding the projector).

Mediation requirements

The installation is designed to function on its own and requires minimal supervision or maintenance. The only requirement is to turn the projector and LED lights on and off in the mornings and evenings. If the need arises, basic adjustments (such as camera alignment with the ring) can be performed by the mediator via a simple mouse-driven interface. Any software issue can be handled remotely by the artist via a remote desktop connection (TeamViewer).

Other requirements

A reasonable-speed internet connection is required (wired or wireless).

Below are minimum space requirement diagrams:

Updated October 2021