Ian Shelanskey

Qlab 3 – Projector Alignment and Masking

This Qlab show was created for a small dance concert at the University at Buffalo called Zodique Dance Emsemble. I took the role on this show as systems technician and programmer. The projection surface was 4 white ” Streched Sails” which spanned a 40′ black back drop.0428141310

I used two wide lens Sanyo projectors side by side with no overlap. Total surface resolution was 1600X600.



 I used the Qlab alignment grid by checking the boxes that say grid. This grid makes it easy to align two projectors by just matching the grids. By slowly adjusting the projector feet, I aligned the two projectors together where they meet.

Due to a space constraint we could not have the projectors exactly in the middle of their own projection surface, meaning the images perceptive was skewed. Qlab has a way to fix this with corner-pins.

Nudging the corner-pins allows you to make the grid square and this means your content won’t be displayed funky.

After adjusting the corner pins, we can accurately mask out the negative space of the sails. Qlab does not have an on-board masking tool, just the ability to apply a mask. I saved the grid image and loaded up Gimp to create a mask. Using the grid on stage as a reference I mapped out the positions of all the negative space and applied a gradient to all of the edges that would have otherwise shown.

Quick tip: If you save the image and apply it you can make edits and re-export and Qlab will automatically refresh with the update.

After applying the mask to the surface in Qlab, I loaded an image to see the result.


Everything lined up beautifully, There was a visible seam between the two projectors due to the age of them. There was a weird color green purple color gradient that couldn’t be color corrected. If I had to do this project again I would overlap the projectors to try to get rid of the seam.

Zodiaque Dance Company: Celebration 40 Projection Technology

This was a fun project that I took on at the end of the semester. Zodiaque Dance Company is The University at Buffalo’s premiere dance company and they were celebrating their 40th anniversary this year by inviting back alumni designers, dancers, and choreographers. In addition to this they also decided to have a large projection slideshow and movie about the history of the company. The projection designer developed a projection screen arrangement which consisted of 6 screens.

My job was to develop a system to control the projectors.

The Constraints:
The six projectors had to display different things on different screens at different times.
All projectors needed to be controlled from one computer.
Content need to be able to be edited quickly during tech.
And as always, make it as cheap as possible.

The solution I came up with was to use 3 computers, all running QLab 3. Two of them actually had projectors attached, the other was the master computer to keep them in sync. The two remote computers have the content on their local drives and loaded into a cue stack on cue lab.
The master computer sends out OSC commands to the remote computers to play the slideshows or videos.
OSC commands are interpreted and the cues are executed by the remote computers.

Check out the Signal Path here.

The 2 remote computers monitors could be seen from the master computer via screen sharing over the network.

This system was used in lieu of purchasing expensive software and media servers which run upwards of $60,000. We ended up only renting the projectors and the VGA cable runs.