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Pyschopy windows output redirection

We are running experiments on our jupyter notebook by importing the python psychopy library.
We would like to see the psychopy window experiment output on the connecting client not on the server were the jupyter notebook is running.
This is happening also with vnc clients.
Is it possible to redirect psychopy window on the connecting client?

We don’t want to tun experiments online on pavlovia !

Thank you

PsychoPy code generally needs to know when the window has been refreshed - so it needs to be running on the local machine to be able to talk directly to its hardware (i.e. the graphics card). Pavlovia can achieve this, because the user downloads javascript that runs locally in the browser, not just remotely on the server.

So even if you could find some way of mirroring output to the connecting client, it would not have reliable performance, and I’m not sure how you would collect responses either.

This does seem a bit of a Frankenstein solution, as opposed to running on Pavlovia, which solves all of these issues for you. What is the reason for avoiding that route, which would be much simpler?

Hi Michael,

Thank you for answering my question. Pavlovia is not a free platform and in our case we have to pay for each participants roughly 50 participants.

Thank you

Fifty participants would only cost £10, which is considerably cheaper than alternative platforms (though some may currently be waiving their fees – you could investigate I had an email from them saying

If you wish to make Testable one of the tools to mitigate the impact of COVID-19 on students’ classes and projects, please email us a request from a person with the appropriate authority and we will see that a full departmental license covering all your staff and students is put in place asap.
However, they couldn’t provide the functionality I wanted and learning how to put PsychoPy online was more attractive than learning a new system.

If you have a very simple experiment then you might be able to use PsychoPy 2. Here’s an experiment I ran on my own server in 2018.

If you want to use current functionality for free then you would need to teach your participants how to download and run PsychoPy locally and then email you their data file, or share the experiment with them so they can pilot it and again email you their data file.

Even at minimum wage, all of these workarounds are going to be more costly in time than using Pavlovia.

Best wishes,


Thank you Wakefield I’ll pass your info to our researcher.


For perspective, you are probably dedicating several thousand euros worth of your development time to pursue a complicated technical solution that is unlikely to work, in order to save about 11 euros of server credits. I’m not sure that stacks up.

Hi Michael,

Well today the researcher I’m working with, decided to use a different online experiment service qualtrix.

I’m not the budget decision person, I’m just a system admin that got a request to make this working for them, I was unaware of hardware and sw constraints of the pyschopy library until I embarked in this very painful journey.

In my opinion psychopy (for the online experiments) is a proprietary platform. Ideally it should provide a way to render experiments output to the web client without using a third party (paying)service like pavlovia.

I want to thank you for your prompt answers and for the help



Hi Marcello,

Good luck, I hope it all works out.