How to record time - not duration

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How to record time - not duration - of stimulus onset?

How to record time - not duration - of stimulus onset?

Author	Message
marieke_01	marieke_01 posted 10 Years Ago Topic Details Share Topic
Group: Forum Members Posts: 1, Visits: 1	Hello. We want to supervise by video if a participant has really observed the presented stimulus. Therefore, we need the time, when the stimulus was presented. With "stimulusonset" it´s only possible to record the milliseconds after the trail began - thus, a kind of hold-up effect control. But we need the time - in terms of time of day (10:12:13) or the milliseconds, counted scine the beginning of the whole experiment. Who can help? Thank you, Marieke Tags stimulus onset time recording
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Dave	Dave posted 10 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 12K, Visits: 98K	You'll want to make use of the applicable 'currenttime' and/or 'elapsedtime' property to record a timestamp /ontrialbegin, log that to the data file and then add stimulusonset to the timestamp to approximate absolute starting time for the given stimulus.
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juhaso	juhaso posted 10 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 2, Visits: 13	Thank you for the very nice possibility, to include a timestamp of the inquisit-events in the logfile via <data> / colums =[...,script.currenttime,...] </data> However, to synchronize inquisit-events very accurately with an externally recorded video (with timestamps) it would be very useful to have a inquisit-timestamp including milliseconds, e.g., in the format hh:mm:ss:xxx where xxx are the milliseconds. Is there any possibility to have that?
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Dave	Dave posted 10 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 12K, Visits: 98K	No. The currenttime property does not provide milliseconds. elapsedtime, however, is provided in milliseconds, so if need be you could conceivably combine the two (using math via expressions).
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juhaso	juhaso posted 10 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 2, Visits: 13	Actually that does not help much. If I find script.currenttime script.elapsedtime 12:13:23 41291 12:13:33 51391 in my logfile, I know that the trial startet at second 23 and lastet for exactly 10 seconds. However, I don't know exactly when it started. That's to unprecise to sync it with a videorecording of 30 fps which records a frame every 33 ms. My workaround-solution is to wait for a "full" second: ------------------------------------ ### Start experiment-block if second is "full" ### (Inquisit 3.0.6.0) <expt> / subjects = (1 of 1) / blocks = [1=loopfullsecond] </expt> <values> / beginningSecond = script.currenttime </values> ######################### ### "full second" loop ######################### <block loopfullsecond> / branch = [if (script.currenttime > values.beginningSecond) block.experiment] / branch = [if (script.currenttime == values.beginningSecond) block.loopfullsecond] </block> ######################### ### Experiment starts ######################### <block experiment> / trials = [1=experiment] </block> <trial experiment> / stimulustimes = [0 = experiment,currenttime1,currenttime2,elapsedtime1] / timeout = 5000 </trial> <text experiment> / items = experiment / valign = center / halign = center / position = (50%, 50%) / txcolor = (0,0,0) / fontstyle = ("Arial", 5%) </text> <text currenttime1> / items = ("Script start second: <% values.beginningSecond %>") / position = (50%, 60%) / halign = center </text> <text currenttime2> / items = ("Current time: <% script.currenttime %>") / position = (50%, 70%) / halign = center </text> <text elapsedtime1> / items = ("Elapsed time (should be lower than 1000): <% script.elapsedtime %>") / position = (50%, 80%) / halign = center </text> <item experiment> /1 = "Experiment starts" </item> ------------------------------------ The script itself seems to need about 32ms to get up and running on my machine (measured with a very simple script and script.elapsedtime). That's an offset of one frame and acceptable/assessable for me. Nevertheless, a more precise timestamp would be very useful ;-)
	Like 76