Highest Resolution Wall Around

akhaksho writes "NCSA (the National Center for Supercomputing Applications) is in the process of building the highest resolution display wall in academia. This is similar to the previous story about the wall at Sandia, but the intention of this wall is to get very high resolutions at a reasonable cost using off the shelf technology (for the most part). All of the code to run it and plans for the physical infrastructure will be available as part of the Display Wall in a Box effort. I'm one of the guys that built this sucker (and have the scars to prove it!) "

Comments

Re:The resolution actually isn't that good, is it?

[akhaksho]

Actually it is 4 projectors wide and 5 high. The screen is 9'x12', but the image is about 8'x8'. Each tile is about 2 ft. wide. You're right that the resolution in dpi is less than a monitor, but there are no monitors that can seamlessly display 4096x3840 or 8192x3840. The idea is that you can look at a large dataset and see the whole thing without panning and zooming. It will definitely be used for "real work".

Cool! The Prime Radiant is next

[gentlewizard]

In Issac Asimov's third novel in the Foundation series, Second Foundation, mathematicians used a video wall projector to display their equations. As described in the book, the Prime Radiant did not cast a shadow, yet the walls were covered with equations. The coolest thing was, you just thought about a part of the equation and those lines marched down the wall to eye level. So combine this video wall with the mind-activated cursor talked about in this issue of Wired and we're almost there.

A couple of nits

[Jeffrey Baker]

Twenty times the number of dots as a typical PC sounds a lot like tired claims of "50 times faster than a phone modem!". This display has basically five times as many dots as the current high-end of CRT monitors. If you are going to build a high end system, you have to compare it with other high-end systems.

The other thing that gets me is the use of the term resolution. In raw terms, this display actually has very poor resolution: about 28 dots per inch. If you stand way back from it, it might have a high number of dots per degree of arc of vision. But then, how bright is it from 100 feet away?

Re:One of the nits

[Liquor]

A resolution of 28 DPI sounds low until you figure that a typical display is only in the 72 to 100 dpi range, and is viewed from only about two feet away. A screen 18 feet wide by nine feet tall is unlikely to be looked at that closely -- It's more likeley to be viewed from about 10 feet or more away - any closer would effectively prevent someone from seeing the whole picture. And at that distance, that's the same apparent size per pixel, or better, than even high end monitors and displays.

As for brightness - as you get further away from a uniformly emitting planar surface, the brightness per unit angular area remais constant - merely the apparent total area decreases. If it's bright up close, it's bright enough at any distance at which it is a significant part of your field of view.

And with a fairly high powered cluster to generate the graphics, this can probably render animations of various problems (e.g. turbulent airflow over a surface) in real time on a 1:1 scale - not to mention 3d walkthroughs of complex structures and simulations of advanced weaponry.

Quake, anyone?

Astonishing, but how does it really benefit?

[starseeker]

This is an honest question, not a troll. I have been trying to think of what types of data display you could do on this type of screen that you couldn't do with more conventional technology. If it is sheer size you want projection technology can do that, and if you want fine grained imaging you can use high resolution computer monitors and zoom in and out. How does this really large, finely detailed display benefit the research? Again this is an honest question. The cost of this thing cannot be trivial. What do you see here that you can't see anywhere else?

Don't get me wrong, I'm all for technology for it's own sweet sake. But I'm curious how this is cost justified. Those reasons/rationalizations could prove very useful. (I doubt anyone I am likely to work for would consider Quake sufficient motivation, now that the golden days of the dot coms are over. Maybe these guys are just the coolest folks on the planet :-) So, anybody have any ideas?

Re:Astonishing, but how does it really benefit?

[akhaksho]

One of the drivers for this wall is a scientist we have here that has 8kx8k images of radio astronomy data. He wants to be able to compare different regions by eye. Panning and zooming on a small monitor doesn't cut it. If you're going to image or calculate high resolution data, you don't want to throw it out when viewing.

Do you really need 40 PC's? And GeForce2's?

[Nehemiah S.]

I guess i'd have to be more familiar with the WireGL and how it renders frames, but as long as most of the crunching is done on the video cards, I would think that you could do this with many fewer systems. Especially since you are only running at sub-1024x768 resolution per screen. How about 4 dual athlon PC's with 1 AGP and 4 PCI dual-head cards each? That would still give you the same number of pixels, at a significant savings in hardware cost.

Although you probably couldn't play quake on it, could you do most other things?

Neh