Issue with moving stimuli

Support
1

hi guys,
im having a number of issues with presenting moving stimuli.

  1. Im not making use of the ‘movie stimulus’/‘drifting grating’, since apparently it doesn’t work with the Tangent Screen on: what Im doing is basically generate frames of the stimulus (e.g. grating) at different views (phases), and then load one frame at the time (which I guess is the same thing the movie stimulus command does)
  2. main issue: the movie generated with different frames takes some time to start, meaning, the first frame stays on for a number of seconds and then the others are shown properly. this holds every time a stimulus like this is presented for the first time (the next presentations are correct). plus, the problem is not solved by unchecking the ‘defer loading until queued’ option.
    thank u!

fede

2

Hi Fede,

Im not making use of the ‘movie stimulus’/‘drifting grating’, since apparently it doesn’t work with the Tangent Screen on

I’m not familiar with the tangent screen. I guess it’s something Dave has been working on?

In any case, it seems like it shouldn’t be breaking the movie and drifting grating stimuli. We should definitely figure out why that’s happening.

what Im doing is basically generate frames of the stimulus (e.g. grating) at different views (phases), and then load one frame at the time (which I guess is the same thing the movie stimulus command does)

That is indeed exactly what the movie stimulus does. The reason it exists is that you can’t ensure correct and consistent frame timing with explicit queue/update/dequeue actions, which may be exactly the issue you’re dealing with. We should definitely figure out why the stock dynamic stimuli aren’t working for you.

Chris