Multi Projector Installations – Perfection is pricey, but “pretty darn good” is affordable

One of the coolest features of Euro RSCG New York’s MadSci Lab is its 30 foot projection wall.

We started out naively enamored with the potential for a large screen display using commodity short throw projectors and a NVIDIA Surround SLI enabled PC.

All of this is quite affordable; 3 projectors at less than 1k each, and a mid-range gaming PC (Under 2K) with a few extra video cards ($200 each). We started off with the machines on the floor and got it all working. The immediate WOW factor was indisputable, especially with some full screen 3D content running on it like Portal 2 or Black Ops. The seams between the images was tolerable and in some cases even ignorable.

Eventually we got around to mounting the projectors on the ceiling which was problematic; the inexpensive projectors we chose aren’t very adjustable so we had to get them in exactly the right spot, which was made more difficult by lighting fixtures and a drop ceiling. With some clever hacking/engineering we solved that by using some wire shelving as our mounting plate, which gave us some flexibility to move the projectors around once we mounted them.

After a few weeks the initial WOW subsided and we got down to business. But over time we received more and more requests to use the room (now the coolest room in the agency) for New Business Pitch meetings. In these settings, people under intense pressure to have their art look perfect for a client, weren’t very happy with having to work around the screens limitations. Content that went across the screens didn’t line up perfectly and slight color differences with commodity projectors just weren’t acceptable. We spent hours tweaking and aligning but we really couldn’t get it close enough to what the creatives demanded.

As we started to do the research about how to have a perfect multi projector setup, we were amazed by the complexity and expense that was involved. There are several approaches to solve these issues but most boil down to warping and edge blending. Warping is adjusting the image to compensate for minor alignment problems with the projectors. We found some VJ software that had built in warping and edge blending, called Resolume Arena, but it required us to always prepare graphics in a certain way and didn’t really give the point and click interface people are used to with powerpoint or quicktime players.

Initial research turned up a myriad of expensive solutions. Enterprise quality software only solutions (one charging 3k per projector), dedicated hardware boxes (4-10k), and combinations of specialized video cards and projectors. All of these were appearing to require 3x-5x the investment of our humble 5k rig. I had seen a few references to simulator products that touted edge blending such as Warpalizer and Nthusium, but I couldn’t find any information about desktop level support, meaning that every app we use would be handled by the warping and edge blending. We had practically given up and started putting together a much more expensive plan for phase 2, when I stumbled across PixelWarp DT.

PixelWarpDT is a really powerful and relatively inexpensive solution for multiple projector management. $620 for a commercial license we were able to handle alignment, edge blending and even color adjustments that had originally hamstrung our setup.

PixelWarp DT allowed us to adjust everything we needed to create a new perfect image.

Before:

After:

Notice face color of the woman’s image next to the rainbow on both images. Also notice that there is no longer any seam or alignment issue.

We are very happy we found PixelWarp DT as a solution.

Leave a Reply