In online experiment image gets distorted on some screens

Online experiments
,
1

Hello all! :innocent:
My experiment doessn’t show stimuli correctly on all screens. The image stimulus gets distorted on some screens depending on the screen settings / characteristics.

Is there possibility that my experiment adapts itself to the participant’s screen?

Thanx a lot!

2

What sort of distortion do you mean? Are you using norm units or height?

3

This circle depicted in the image looks oval on mac laptop (waiting to get that laptop screen preferences) . Although it looked well on another mac laptop and on my lenovo.

wheel_v7s9_fullsize
wheel_v7s9_fullsize1920×1080 94.4 KB

I use ‘pix’ units for window and ‘norm’ for the image. It is critical for me that it fits well on the screen because i use it to gather response with pixel-color-reading procedure.

code snippet 1:
// open window: psychoJS.openWindow({ fullscr: true, color: new util.Color([0, 0, 0]), units: 'pix', waitBlanking: true, multiSample: true, numSamples: 16, allowgui: false });

code snippet 2:

``
// Initialize components for Routine “t2_resp”

t2_respClock = new util.Clock();
mouse = new core.Mouse({
win: psychoJS.window,
});
mouse.mouseClock = new util.Clock();
response_wheel = new visual.ImageStim({
win : psychoJS.window,
name : ‘response_wheel’, units : ‘norm’,
image : ‘wheel_v7s9_fullsize.png’, mask : undefined,
ori : 0, pos : [0, 0], size : [2, 2],
color : new util.Color([1, 1, 1]), opacity : 1,
flipHoriz : false, flipVert : false,
texRes : 128, interpolate : true, depth : -1.0
});

``

Thanx a lot!

4

If you use norm units then you will get ovals instead of circles for some aspect ratios of screens. I would recommend height units. The shortest screen dimension (height on a landscape monitor) is set to 1 (-.5 to .5)

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