Showing posts tagged with: Portable Projection Show all posts

Posted Thursday, 19 July 2012

First Shopping List for Projection-Bombing

As discussed in a previous post, I will be powering a projector from a lead acid battery during my residency at I-Park. This is a technique often referred to as 'projection bombing'.

In this post I'll describe the shopping list, and when the parts arrive I'll post some more on how well they work together.

I've never done this before, and have taken advice on electronics, technique, and shopping list from a friend and fellow projection-bomber Andrew Crowe. Here are some shots of his projection bombs at the Occupy protests in London in 2011:

Projection bombs from the Occupy London set by Andrew Crowe, 2011

I also found this post on stack exchange quite helpful getting started.

The shopping list
Bear in mind as you read this, these are the parts ordered, but I haven't used them yet and can't vouch for them. You will have to check back and read future posts to see how well they work together. Here are the parts purchased:

A 12V lead acid battery
A power inverter - this is attached to the terminals on the battery. It draws DC from the battery and supplies AC in a way which mimics 'wall outlet' AC for consumer electronics (such as a projector)
A volt meter - to keep an eye on the remaining charge in the battery during use. I will experiment with the battery and inverter, to find out at what voltage the inverter cuts out at. This is so that I can monitor the battery during use, work out time remaining, and shut down the projector prior to the inverter cutting out
A mains battery charger - this attaches to the terminals on the battery and plugs into a wall outlet, to recharge the battery from the mains between uses

Below I'll describe each part in a bit more detail.

The battery
I had considered either a 75Ah (Amp-hour) battery or a 92Ah. This rating basically tells you the capacity of the battery, or how long it will be able to supply enough DC voltage for the inverter.

12 Volt 75Ah Sealed Lead Acid Battery

My hope is to power the projector for at least two hours - as Andrew Crowe pointed out:

"For comparison I can run my projector off a 45 amp hour battery for just over an hour, so 80-100 amp hours should let you go for 2 hours"

The big problem with batteries is weight. I intend to use a cart to wheel the battery around but it's important to bear in mind that I will be walking along trails at I-Park, not flat paths. I will also be carrying a projector, laptop, sound system, camera, and probably other bits & pieces too.

The 75Ah battery is 60 pounds, and the 92Ah is 75 pounds. It's hard to know upfront just how much of a problem this will be, but I opted for the easier-to-carry option.

The inverter
I calculated that I would have an operating power consumption of 320-330W, based on a projector of 280 or 290W (depending on which projector I actually use), and a small sound system of 40W. I therefore purchased an inverter which supports a much wider 450W.

450W Sine Wave Power Inverter

A problem here is it (probably) means I'll have to power the MacBook Pro from it's internal battery the whole time. The MacBook Pro battery life will be reduced quite a bit anyway because of high CPU load associated with intensive media processing. On the other hand, the battery life could be longer because the screen will be off during performance (the projector will handle all the visual output).

However, in the worst-case scenario, if I decide during testing that I need to power the MacBook Pro from the lead-acid battery, I can just switch to an 800W inverter.

The other problem is that it is said that modified sine wave inverters (as opposed to 'pure sine wave' inverters), while cheaper, can cause a loud hum. I want to experiment with the modified sine wave inverter I have selected and only order a pure sine wave inverter if I encounter problems.

(If you want a nice demonstration of AC vs DC, there are some nice detailed electronics tutorials by mjlorton here, including this one which covers AC/DC with diagrams!)

The volt meter
The volt meter, actually a multimeter, was the simplest choice. I really only need it to tell me the voltage remaining in the battery.

Pyle PDMT02 Multimeter

I don't need to be able to test current or anything else, so the simplest tool will be fine for this.

The mains-battery charger
With the mains charger there are a few things to get right. Firstly, they are each rated to charge a battery with up-to a certain number of Amp-hours. So the inverter I chose had to support a battery of 75Ah.

CTEK MULTI US 3300 De-Sulfating Charger

Secondly, there is the charging speed. Andrew Crowe points out:

"3.3A charging current isn't great, that'll take a very long time to charge ... I'd look for one with at least 4A max charging."

The problem here is that I couldn't source a charger that supported both a 75Ah battery and a 4A charging current... at least not without opting for an industrial solution way beyond the scope of this project.

So my charger supports 75Ah battery with a 3.3A charging current. Extrapolating from figures Andrew supplied me from his experiences with smaller batteries, I estimate that it might take 20-24 hours to charge.

This is a restriction. Sunset will be around 7pm in August in Connecticut. Since I can only use the projector at night, I might like to go out at 8pm each evening and return at 11-12pm. If it takes 24 hours to charge, I will not be able to keep that rhythm and it may impose a 48 hour gap in between performances.

However, if the battery isn't fully charged, I could still go out with a 75% charged battery. And in practice the battery may take 20 hours to charge.

Ideally I would have a 100% charged battery ready to use at 8pm each evening, but we'll see how the tests pan out. It may be that I have to find a better charging solution, or work within the restrictions.

It's also a very fair point to say that this artificial restriction could be useful - it imposes a 'day off' from performances for reflecting, documenting and making changes to the performance in preparation for the following night.

Posted Friday, 13 July 2012

Portable Projection in a Rural Context

In just over a month I will start a one-month residency at I-Park. My proposal is based around 'portable projection', and in this post I want to describe what that means and what I am planning to do onsite.

My proposal to I-Park was that I will appropriate the projection bombing technique (described below), but this time to explore a new approach to my installation work. Instead of scanning, photographing, replicating or manufacturing textures in a studio or gallery, I wanted to work with real, physical objects and textures, which have a life - and unpredictability - of their own.

My proposal is to explore the surfaces and textures of the woodland, by writing software patches which generate 2D geometric shapes, and projecting them as moving video sequences.

The flat plane of the 2D geometric shapes (projected on the flat plane of the 2D projection surface) will be distorted by the underlying natural textures and shapes that the light falls on. In this way, the underlying material will drive the visual artifact in a very direct and immediately perceptible way.

Projection Bombing
When people talk about portable projection they often mean Pico Projectors: very small hand-held projectors with built-in batteries. However these projectors (by nature) are not powerful enough to provide an effective image for bright, realistic video.

The terms 'mobile projection', 'portable projection' and 'projection bombing' therefore also refer to a separate, established technique - that of making a regular, mains-powered video projector portable, by attaching it temporarily to a car battery:

Example of 'guerrilla' projection bombing, Rio de Janeiro, 2007

This approach removes the restriction of position, where a projector can only usually be moved a few meters, or the distance of a power cord. Instead, you need to carry, wheel or drive a car battery around with you to keep the projector powered.

New restrictions
However, with this approach you gain new restrictions. Moving a heavy car battery can be cumbersome, and you can only power the projector this way for a period of 1-2 hours before you need to recharge the car battery - which takes several hours.

The technique is usually associated with a small creative subculture of VJs, street artists and media programmers. It often takes place in an urban context, and has a 'guerrilla' feel - the targeted building surfaces, and projected imagery are often chosen 'on the night', and / or the building owners aren't consulted beforehand.

As with all new techniques ofcourse, media companies have appropriated it to create promotional stunts for their clients. (Compare an original, in 2006 by Karolina Sobecka, with an ad agency version from 2012 inspired by the original).

Textures and surfaces - why projection-bomb in a rural context?
In my previous installation work, I have explored revelation of textural detail:

Gravity, 2011

In 'Gravity', 2011, I was experimenting with the idea of the 'endless plane' which extends beyond the canvass borders. Paintings have long explored this idea, and I was particularly influenced the work of Mark Rothko or Jackson Pollock. Using software and projectors I have been experimenting with the idea that the plane can be slowly revealed, one frame at a time.

Rather than manufacturing a frame, I will be working with found forms and textures on the grounds of I-Park, and temporarily altering the way they are perceived by projecting combined sound and light.

The grounds at I-Park
I-Park is located in a remote, 450-acre woodland with "ponds, hills, streams, stone outcroppings and sheer cliffs" and "wild fields and new growth forest, as well as miles of stonewalls and walking trails". The land "has a wild, gnarly character"... (see the I-Park website).

Some shots of the I-Park grounds, by Fabio Battistetti, 2011

Jim Sanborn
A good place to get a sense of what this will look like is the work of Jim Sanborn, an American artist and sculptor:

Lo-res stills from 'The Topographic Projections and Implied Geometries Series', 1995-97

(Sanborn is a prolific artist, better known for the sculpture Kryptos, outside the headquarters of the CIA, which contains an encrypted code which to this day has not been fully decrypted.)

For the 'Topographic Projections and Implied Geometries' series, Sanborn used a portable projection technique similar to the one employed in projection bombing, but much more 'planned'. From Sanborn's portfolio:

"These images were produced by direct, large format, light projection. The projector, powered by a mobile generator, was moved from site to site. All of the pieces were photographed at night using long exposures. On moonless nights, the landscape was lit with searchlights. The landforms themselves are quite large, requiring the projector and camera to be, on average, 1/2 mile away from the subject landscape."

Looking at Sanborn's work makes clear a few important questions that I have to consider.

1. The decentred viewer?
Firstly, due to the remote locations, audiences will rarely directly perceive the work. Dissemination relies heavily on documentation, and therefore documentation takes on an importance equal to that of the artwork itself.

This is troubling for an installation artist. Mainly this is because by providing a 'frame' from which to view your work, i.e. a photographic or video frame, you are taking away all other possible perspectives of your work. You are eliminating the 'decentered viewer' as described by Claire Bishop, and you are putting a nail in the coffin of viewer participation too.

However the way I am choosing to look at this is that it is a sequence of short intervention experiments. The end result it may lead to is unknown to me. This may become a performance, it may lead to other directions for installations, or it may be the last portable work that I create. It's hard to say, but that's the nature of experimentation.

2. Differentiation
Since Sanborn's work is aesthetically so similar to that which I am hoping to achieve, it becomes an interesting point of departure. It forces questions about what is the essential nature of my proposal, and the question: What is it that I hope to achieve beyond or seperate from what Sanborn has already achieved?

The first thing to note is that Jim Sanborn's work is beautiful. It is also large-scale, well-funded, and very carefully considered work. What I am planning for I-Park is very ad-hoc and small-scale by comparison.

But putting that aside, there are also conceptual differences. These differences have a lot to do with the influence of digital culture in 2012. But on closer inspection they are also centred around intention, presentation, appearance and dissemination.

Generative sound & video
I will be working with a laptop and a projector. The laptop will run software which will produce video and sound simultaneously. The software will produce those media 'on the fly', which means that unlike Sanborn's work mine will be 'generative' and changeable (and as such, bears the relevant nods to John Cage, Brian Eno, Sol LeWitt, and many others.)

The sound and video will be created together and, ideally, will exist as a single entity. Data from the one will feed the other, as in the work of Memo Akten:

Simple Harmonic Motion study #5d by Memo Akten

Where Akten's work is purely pattern-based, I will introduce a certain amount of randomness. This is very much intentional. Each evening I want to go out and perform a short (1-2hr) experiment, allowing patterns to generate and run.

The next day I want to try a new pattern, software patch or set of geometries, influenced by the previous evening's work, but never fully take control. There is a fast turnaround and each installation will be fleeting, but each installation will also be surprising, since it will not be defined upfront.

Borders & masking
Where Sanborn allows the natural borders of his patterns to be exposed, I intend to 'mask' my projections in the 'projection mapping' style:

Projections mapped over vines

The main reason for this is that Sanborn used either moonlight, or search lights to expose the non-projected areas. This makes sense with long-exposure photographs but moonlight will not make a difference to video. This is potentially an area to be explored.

Another difference which may exist (I will find out when I do it) is that my work may expose a little more of the technological mechanisms which produce it. This isn't necessarily by design, but with a lower budget and a car battery rather than a generator, the projector used at certain angles may show pixels, or differences in brightness over extended distances, or other artifacts that I haven't thought of yet. This isn't my intention, but it will be interesting to see what effect this might have.

The purpose of documentation
In Sanborn's work, the time dimension is noticable. The long exposures mean that stars in the night sky are captured moving from position to position, which gives a subtle but powerful sense that these are not just 'recordings' of events, but are events mixed with recording techniques.

It's hard to see where the recorded event ends and the recording technique begins. They are fully intertwined, since the represented event in the documented image was never really experienced by a human in quite the way it is presented.

With my work at I-Park, the recorded documentation will be in video form. The role of the video will be to demonstrate the installation as recorded from a particular angle, as faithfully as possible. The primary focus of my work will be the live event, and the video recording will be an attempt only to reproduce that event for dissemination, not to become part of the work as such in itself.

However although that's the intention, inevitably the recorded events will become a lens through which the work is viewed, and therefore can't fail to have a big impact on it's perception. But as discussed above the future of the work is open-ended - it was concieved as installation and as a work for direct perception by audiences, but the emphasis may change depending on the results.

Dissemination
I want to publish the work online as I go, week by week. This means I have the potential to get external feedback as the process develops, rather than after delivering the work at the end in a gallery or presentational setting. I'm viewing this residency as an open-ended experiment.

With that in mind, it makes sense to try to initiate a group of interested individuals before I start, designers, software developers, artists, who might be interested in commenting on the experiments.

I'm looking forward to starting the experiments, and will be posting more info about the preparation work I'm doing over the coming weeks.

Posted Wednesday, 2 May 2012

Visit to Cold Spring

New York state has some outstanding areas of natural beauty. On Sunday we hiked up a trail in Cold Spring, and brought back some photographic evidence.

I want to talk in this post about some of the discussions that came up as we walked, and the way they are affecting how I'm thinking about my upcoming projects. I'll illustrate the text with some shots of our hike.

I met Hannah Gould, and as we hiked she told me about her father's studio out in San Jose, California - and their mutual admiration of Andy Goldsworthy. Bill Gould creates various types of physical sculpture, signage, fencing and gates for public locations.

It seems possible that I could arrange a trip to see him and spend some time in the studio creating work inspired by land art.

It all seemed to tie in very nicely with the plans I have been making for I-Park. It feels like a cloud is forming around this idea of 'land art', portable projection, and visual-sound correlation.

I'm beginning to see several disparate concepts converge. All of which I can come back to, flesh out and consider over the coming months.

Spatial augmentation and exploration
I'm really interested in thinking about the way that we consciously and unconsciously project value onto objects and environments around us. 'Nature' and 'natural objects', rocks, trees and rivers, are perceived with a given context based on the historic demographic context of the observer. In the work I produce I want to think about the ways my augmentations of these objects affect this sense of value.

Land art
For example, in the arrangement of natural objects in the traditional sense of land art, do we 'humanize' the object, in making it more relevant to us? Or are we moving closer to nature, in the sense that we are augmenting natural objects by revealing natural patterns?

And one step further from that, does it really make sense to demarcate 'natural' and 'human' and to posit them on either end of a scale?

Working with natural textures
And what happens to this conversation when we introduce digital elements?

If I project algorithmically-constructed patterns as light onto a naturally textured surface, does this do anything more to the surface than can be achieved with the use of natural materials alone?

Will the strictness of the algorithmic geometry work against the endless unpredictability of the natural texture? Will this form a disconnect, and what might this disconnect say about the demarcation between 'natural' and 'human'?

And does this disconnect occur in 'pure' land art?

I've always preferred 'natural' texture to algorithmically-generated ones (i.e. Perlin noise), and so I'm fascinated by the idea of projecting onto them. So much projection mapping is designed to attack as geometrically 'perfect' surfaces as possible, it will be really liberating to explore with the purpose of highlighting the 'flaws' in the surface rather than concealing them.

The synaesthetic effect
The aspect which excites me most about digital projection right now is the way it can be linked in real-time to other perceptible events - in particular simultaneously generated sound. Some people call this the 'synaesthetic' effect, though synaesthesia is about much more than just vision and sound.

Walking with Gene we discussed potential experiments we could work on with SuperCollider, and combining it with VVVV. Gene is passionate about SuperCollider at the moment, and we have already agreed to collaborate over the next few months before he goes to India.

These experiments, along with the land art training in Bill Gould's studio could provide a really solid base for the work I produce at the I-Park residency.

The technical part of portable projection
The one and only reason I am interested in 'portable projection', is so that I can walk off with a projector to a remote location and not have to worry about a power source. The way I've seen this achieved is by connecting a car battery to a projector. There are ofcourse pico projectors, but these have nowhere enough lumens to make a convincing 'coat of light'.

The car battery approach means that each projection will have a very ephemeral nature. The projector will need to be switched off shortly before the power runs out. This gives only about an hour, including set-up and mapping time.

Computer Vision and quick mapping
Gene is also very interested in projection mapping, and he is particularly interested in using Computer Vision libraries to create a real-time automapper using a webcam. This could mean that software could continuously scan a webcam feed, and use edge detection and other algorithms to continuously redraw it's internal representation of projected surfaces. This in turn would mean that as you move the projector around the object, the 'coat of light' applied would continuously update (a considerably lower-tech version of this).

This is lofty stuff, but I am interested in exploring this because it could speed up the mapping process. Which, when you are time-limited by battery life, would be a really positive thing.

I will come back and look at these subjects more in the coming weeks, to see where a little fleshing out takes them.

Posted Sunday, 29 April 2012

Residency at I-Park

I have just accepted a residency at I-Park, Connecticut starting in mid-August 2012!

The I-Park house

I-Park is a unique space - it is a woodland retreat, and the work I do will be embedded in the natural environment. This is a first for me, having always exhibited in cities (although not always in a whitewall gallery!)

From the I-Park website:

"I-Park is a 450-acre woodland retreat in rural East Haddam, Connecticut. The property consists of ponds, hills, streams, stone outcroppings and sheer cliffs. It has wild fields and new growth forest, as well as miles of stonewalls and walking trails. It is bisected by the Eight Mile River and adjoins the Devil's Hopyard State Park and other preserved tracts. The land has a wild, gnarly character that suits I-Park's role as a refuge from and recourse to the safe routines and subtle compromises of the workaday world."

I will be experimenting with the intersection between portable projection and land art, inspired by the work of Shaun / PRICKIMAGE, and my friend Andrew Crowe. I will keep this blog updated with my preperations and progress. So watch this space!

My friend and fellow resident at Jaaga, Heather Dewey-Hagborg created a piece for I-Park in 2010, entitled Bower. And there is a long list of previous fellows who have created work at I-Park since 2001.

This will be a great chance to get out of city life and produce something unique and different!

First Shopping List for Projection-Bombing

Portable Projection in a Rural Context

Visit to Cold Spring

Residency at I-Park

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