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How to solve alert 3115?

after I upgraded the psychopy to the newest version I get this alert 3115 which I don’t understand what it means or how to solve it.
Specifically, I have a sandwich priming task where first a fixation point is presented for 1000ms, followed by the target for 27ms and then the prime for 70ms. This has been created in the same routine.
Before I could run the experiment without any alerts but not anymore.

Thank you

Could you post the entire error message?

The alert has a link to further information online (right?).
Have a read of that and come back if it still isn’t clear? But the short answer is going to be that your stimulus durations of 27ms and 70 ms aren’t possible on a standard 60 Hz monitor. They never were, but we’re now pointing it out explicitly before you run.

yes, I read the explanation but I guess it made more confused. since I’m replicating a study my experiment is based on these durations. Does that mean that in a normal laptop screen the stimuli won’t be visible?

Well, most likely it means the experiment you are copying also didn’t achieve the timing it claims. Or maybe they used a monitor with a higher frame rate. You’d need to look in detail at their methods.

A standard monitor can present stimuli for 1 frame (16.666667 ms), or for 2 frames (33.333333 ms) or for 3 frames (50 ms) and so on. If you request 27 ms then the outcome is unpredictable but, most likely, you will receive the nearest time greater than the one you request (33.33 ms). Different software packages will handle the discrepency differently, but none will give you the 27 ms you were expecting.