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PsychoPy3 could not detect the projector (Mac)

I am running PsychoPy3 on Macbook Pro (Mojave 10.14.6).
For some reason, my PsychoPy3 always plot stimulus on my MacPro screen, instead of the projector (Lightcrafter). (My Macbook could detect the projector as a second screen.)
When I go to the Monitor Center, there is only one screen there:

I also tried to change the screen number in the Experiment settings to 0,1,2. The stimuli are always plotted on my Macbook’s screen:
It seems PsychoPy automatically names my Macbook Screen as ‘TestMoniter’. I don’t know how to check the name of the projector…
Anyone know how to detect the second screen or what script should I write in Coder to have the stimuli presented by the projector?

Thank you very much for your help!


PsychoPy doesn’t define the monitor characteristics for you (for example, it can’t know how far away it is from the observer and what its physical size is, although it can detect its pixel dimensions). You need to create a new definition there - the testMonitor entry is just a placeholder default entry. So create a new one and fill in the relevant measurements for a particular monitor.

Then in your experiment settings, use the name of your specific monitor definition, and indicate which screen it should appear on. This might differ from the numbering you Mac displays to you - I think the Mac will present screens numbered, 1, 2 and so on, although the actual numbers under the hood start from 0, so subtract 1 from the number you see in the Mac system preferences when you push the “detect displays” button.