LED art Jim Campbell - how would you do it?

I have been interested in make some LED art works like Jim Campbells works.
He constructs large panels of LEDs using 600 or more LED's for each work and I wonder how can I do this two.
I can drive up to 480 LEDs off a standard computer power supply, but any more would require a 2nd PSU due to the AMPS been used.

One way I have thought of is doing it mostly in hardware. I mean having each LED connected with a set of different resistors and (reverse current) diodes for it different brightness level
and switching the power to the different banks to perform the animation.

Any thoughts on this most welcome.

Below is a lecture by Jim Campbells at Stanford University.

http://www.jimcampbell.tv/

One way I have thought of is doing it mostly in hardware. I mean having each LED connected with a set of different resistors and (reverse current) diodes for it different brightness level

No that is not the way to do it.
You need to control the LED brightness by using PWM. I have not had time to look at a one and a half hour lecture so I am not sure what he does. Can you summertime it?

... or give us an exact timestamp in the video so we don't have to watch the whole thing ...

This might give you a better example of Jims works. Jim Campbell: Portfolio: Low Resolution Works: Running Falling Series: Ambiguous Icon 5 Running Falling
Without watching the 90min lecture. Jim uses 768 LEDs in A matrix of 32 x 24 (768 pixels) and runs video loops on them. A lot different than my thoughts of different power banks...

Mike is right is in saying that it must be some kind of PWN control and I have been searching for arduino matrix pwn led control , to see how others have done this.

Are you sure that is an arduino?
I would say the arduino doesn't have enough memory or speed to do anything like that.

A matrix of 32 x 24 is 96 bytes per frame. Assuming you have all the internal memory available for storing the image that gives you about 20 frames, enough for less than a second of video.

Refreshing a matrix that big is going to consume a lot of time as well, see:-
http://www.thebox.myzen.co.uk/Workshop/LED_Matrix.html

It's not an Arduino, he built his own hardware to do that.

Thanks to the link to your matrix documentation, very useful. Have you a link to the brightness support in a matrix?

I'm thinking of using more the one Arduino to help get around the speed/memory issue.

Check out this thread:-
http://arduino.cc/forum/index.php/topic,72474.0.html

Thanks Mike, that's what i was looking at doing.