[solved] check calibration and use recalibration (if needed) during experiment

yaelholz

Hi,
I'm using OpenSesame 3.0.5 and PyGaze.
I have an experiment in which every block contain 5 stimuli (with fixation point of 200 ms between every one of the stimuli) and 6 seconds fixation point between blocks.

I would like to know if ther is a way to check the calibration (during the 6 sec fixation between blocks), and if the calibration is lost (because of head movements for example...) "pause" the experiment and enables a "new" (or a quiq correction) calibration (and then continue the experiment)?

I saw that there are functions as:
eyetracker.drift_correction(pos=None, fix_triggered=False)
eyetracker.fix_triggered_drift_correction(pos=None, min_samples=30, max_dev=60, reset_threshold=10)

But I'm not sure if this functions (or other function) can help me (and how to use them).

I would be grateful for any help!

Yael

Josh

Hi Yael,

Have you tried the drift correction item yet? It's the green colored icon in the pygaze item group. When you click on this item you can also choose the fixation triggered option, so that the experiment will move on automatically without requiring a button press.

Cheers,

Josh

yaelholz

thanks! works great!

I have one more question-
If, in addition to the drift corrections, I want to create 1 (or maybe 2) brakes along the experiment (because it's 40 minute), is it possible to stop recording and then start recording again (with a new calibration and validation) when subject come back from brake?

thanks,
Yael

Edwin

Hi Yael,

The easiest way to do that, is by simply giving the participant a brake in between blocks. If you hit Q on the keyboard during the drift check, the system will take you into the calibration and you can recalibrate it.

Good luck!

Edwin