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MIT Student Gets Artistic With LED Art
Gibbs-Duhem writes "An MIT graduate student has up a page showcasing a standout art project. He's designed custom LED light fixtures which are seven times brighter than the closest similar commercial models, and include colors which can't be reproduced by a normal RGB cluster (including two ridiculously bright UV LEDs). The result: some beautiful mixed media artwork. The author's goal is to eventually publish a guide to make getting into creating such artwork more accessible to the general public. The site includes lots of great photos and a movie of the art in action. It also has in depth descriptions of the theory involved in this relatively new form of art, an explanation of how the paints were chosen, and an in depth technical discussion of how such lights are designed with schematics and board layouts for those who might wish to build their own lights."
I haven't read the whole article, but anything having to do with LED technology is interesting to me. It's interesting, though, that the author doesn't seem to understand color mixing in pigment vs. light.
He says-
"You mix red paint and green light, you get what appears to be yellow light."
That's not true. If you mix red LIGHT and green light, you get what looks like yellow light. If you shine green light on red paint you get a ugly dark mess. The red paint doesn't reflect the green light very well- the reason it's red is because it reflects the red portion of the spectrum. So, when you light it with green, the light that's reflected off the red is not going to be very intense, it certainly won't be yellow.
Also important is the fact that green is a primary color in light, while yellow is a primary color in pigment. If you shine green light on yellow paint, you'll actually reflect a lot of green, and if you shine yellow light on green paint it'll also (you guessed it) reflect lots of green.
I think it's interesting that he's finding out how the horrible color rendition capabilities of LED's can be used to one's advantage, but I don't know if he really understands all the theory involved...
I got quite bad eye-burn from a UV spotlight (was standing about 2 metres from it for about 2 hours): not a nice experience.
Didn't notice any effect until about the following evening (thought something was in my eye). I woke in the middle of that night with stabbing pains in my eyes. Next day, daylight hurt my eyes. I couldn't even look at the flame of a candle. Thankfully, eye ointment soothed it and the problem eased the next day (disappeared over the next two or three).
Doctor couldn't figure out what had happned to me - I only figured it out (after the visit) cos the weather was cold and relief of cold breeze on my face made me realise I had got sunburnt!
Well, speaking from the event production industry (lighting for theatre, film, concerts and conventions) I don't see it coming that quickly. There are ways for LEDs to take over this industry, but they all depend on some other technology or innovation happening first. LED based fixtures are starting to be used as a tool, but they are in their own category, not as a replacement for an already existing tool. The problems that LEDs have are their color rendering index, their lack of brightness and the inability to dim them via the equipment currently used in almost every theater and production company in the industry (dimmers, PARs and Ellipsoidals). Color rendering is being addressed in the same manner as this MIT student (Selador's x7 series uses 7 different color LEDs to expand their palette) and brightness is fast becoming a non-issue as 3 watt LEDs are becoming commonplace. But dimming is the deal breaker as the industry is saturated with SCR based dimmers that control a majority of the conventional lighting fixtures by way of dimming their main AC input.
For LEDs to be viable, they would have to be able to replace the HPL lamp that is used by the defacto industry standard lighting fixtures: ETC's Source Four PARs and Ellipsoidals. These "conventional" lights plug into distribution cabling that goes directly back to a dimmer rack of some sort where the AC voltage is varied by way of using an SCR to chop the AC waveform at various points thus varying the voltage output and dimming the incandescent lamp. LEDs use DC power and are dimmed by flashing them on and off very quickly (at a constant voltage) and varying the amount of time that they are on versus off to create the illusion of dimming. If you were to put an LED controller onto a dimmed AC circuit, it would fry the controller much the same way that an electric motor would get fried if it were on a dimmed circuit. Sine Wave dimming (new technology) may change this, but that needs to happen first and LEDs second.
There other ins for LEDs to take over this industry. The other half of the lighting industry (seen more in concerts and conventions and less in theatre and film) is moving lights. They mostly use arc based light sources and are dimmed by way of a motorized shutter blocking the light coming out of the fixture. The power input for these types of fixtures is then run separately straight from the power source and not from a dimmer (just like current LED fixtures). They are very bright and have a slightly colder color temperature and lower color rendering index (also similar to LED fixtures). LEDs would be a perfect fit for moving lights and it is only a matter of time before we see new fixtures being developed with clusters of LEDs powering them rather than an arc lamp. The only problem with this is that it is hard to make optics that will still focus sharp with a source that has multiple points of origination.
The final point I will make addresses this problem, I believe. Once you start seeing high powered video projectors running off of LEDs rather than arc lamps (as most are now) then there will be no excuse for LEDs not to take hold of the lighting industry as we are also experiencing another revolution where traditional moving lights whose beams are shaped and colored by metal patterns and glass color filters that are mechanically placed in front of the beam inside the fixture are being replaced by essentially video projectors on moving yokes that project all of the colors and patterns by way of a computer video output. Once video projectors have been taken over by LEDs, THEN I predict, at least in this industry, we will start to see some tool replacement rather than just toolbox supplement.
no one over 25 - I'm over 35, I NEVER watch the cartoon network, I only have basic cabletv, yet I still knew what they were.
didn't do it to get a reaction? - If they intended it to be mistaken for a bomb they would have made it look like a bomb. None of the other 10 or so cities that had identical campaigns over-reacted the way boston did because they had people with at least a modicum of critical thinking in charge. Of course every time something like this happens, it becomes more "normal", so the next "artist" has to come up with something more shocking to get the same amount of attention. And here is the root of your problem - you don't believe in freedom of expression. You are the type who kow-tows to it, but if someone isn't expressing "mom and apple pie" -- if its something that only those damn youngsters can appreciate -- then they have to accept the risk of going to jail for it.