Projector/display changes related to new eye tracker

We now have a TrackPixx eye tracker. It’s from VPixx, the maker of our projector, and it integrates with it. This means we also have an upgraded projector controller box (DataPixx3 instead of ProPixx Controller), and a new monitor for the stim computer. Importantly, the configuration of the displays is different with the DataPixx3. The main point of this post is to explain these changes in the display configuration, and how to adapt existing experiments.

New monitor: The main difference is that the new monitor that duplicates the projector runs at 60 Hz independently of the projector setting. Sadly, even with a 120 Hz monitor it seems it’s no longer possible for the DataPixx3 to output 120 Hz to the monitor. The new monitor also has a higher resolution, showing the projector display in the lower right corner surrounded by black bars, and optionally viewing the eye tracker camera image in the upper left corner.
VPixx might provide a way to remove the black bars when not using the eye tracker, but we might have to accept that annoyance for a while.

Second monitor: Although we now have the previous 120 Hz monitor as the second stim display, it is still highly recommended to turn it off (in NVidia settings) for visual tasks, to avoid screen tearing (vertical sync issues) on the projector. PsychToolbox still complains vigorously when 2 displays are on.

3D: There is a small change on how to set the “top-down” 3D mode in VPutil: for now we have to select the ProPixx before the edid command.

If you would like to test your own tasks with the new setup, please let me know.