# Pavlovia experiment low quality/resolution

**URL:** <https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075>\
**Category:** Online experiments\
**Tags:** screen, online, pavlovia\
**Created:** [June 18, 2025, 10:21am UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075 "2025-06-18T10:21:59Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![adrian\_buechli](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@adrian\_buechli](https://discourse.psychopy.org/u/adrian_buechli)\
**Post date:** [June 18, 2025, 10:21am UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075/1 "2025-06-18T10:21:59Z")

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I’m currently running an online experiment, and I’m encountering a persistent issue with **screen resolution**.

Whenever the experiment starts, everything on screen appears **extremely low-resolution**. I’ve come across a few discussions on the forum regarding this, and the only workaround I’ve found so far is to **manually reduce the browser zoom** (e.g., to 50%), which indeed improves the display quality (attached image).

However, at the **end of the experiment** , participants are redirected to a **Pavlovia survey** , and due to the reduced zoom, the survey becomes **very small and almost unreadable**.

We’re running the experiment on **tablets** , so manually adjusting the zoom between the experiment and the survey isn’t practical or user-friendly.

Has there been any new development or fix for the low-resolution display issue? Or alternatively, has anyone found a way to **dynamically reset the zoom level** before loading the survey?

Any suggestions or updates would be greatly appreciated. Thank you!

 ![zoom_screen_quality](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/0/b/0b7adebeb7064b225a50e2541e42c2ce565ef3fb.jpeg)

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**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [June 18, 2025, 11:37am UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075/2 "2025-06-18T11:37:42Z")

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Hello @adrian_buechli

That’s a difficult topic. See, for instance, [Blurry / low resolution online - #26 by nickpoth21](https://discourse.psychopy.org/t/blurry-low-resolution-online/8364/26). Using height instead of pixels as a size unit seems to alleviate the problem slightly. Various devices differ in screen resolution and consequently in pixel size. When designing webpages, you use the screen resolution to display the variant of your image/graphic that best fits the screen resolution, rather than letting the browser make the necessary adjustments.

See the section on resizing the window [Bringing experiment to full screen after some loops](https://discourse.psychopy.org/t/bringing-experiment-to-full-screen-after-some-loops/13614)

That code should make the window full-size.

```auto
psychoJS.window.fullscr = true;
psychoJS.window.adjustScreenSize();

```

Best wishes Jens

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**Author:** ![adrian\_buechli](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@adrian\_buechli](https://discourse.psychopy.org/u/adrian_buechli)\
**Post date:** [June 18, 2025, 12:47pm UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075/3 "2025-06-18T12:47:04Z")

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Dear Jens,

Thank you for your response, and for linking those posts. I had actually come across them previously and tried the suggestions, but unfortunately, I haven’t been able to achieve any improvement in display quality so far.

I was wondering if there might be a way to force the Pixi.js renderer to display the full canvas at a specific resolution? If there’s any documentation or workaround related to that, I’d really appreciate being pointed in the right direction.

Thanks again for your time and support!

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**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [June 19, 2025, 8:28am UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075/4 "2025-06-19T08:28:29Z")

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Hello

> [@adrian\_buechli](#):
>
> way to force the Pixi.js renderer to display the full canvas

I have no idea how to do that, sorry.

Best wishes Jens

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**Author:** ![wakecarter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/wakecarter/32/5753_2.png) [@wakecarter](https://discourse.psychopy.org/u/wakecarter)\
**Post date:** [June 19, 2025, 3:16pm UTC](https://discourse.psychopy.org/t/pavlovia-experiment-low-quality-resolution/45075/5 "2025-06-19T15:16:50Z")

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Here is my current info on this. I think it’s primarily about Display Scale in Display Settings rather than Browser Zoom – and doesn’t seem to be something we can even detect (to give a warning) let alone alter.

> [@Wakefield's Daily Tips](https://discourse.psychopy.org/t/wakefields-daily-tips/43371/40):
>
> Don’t use polygon borders above 20 Even if you use height units, polygon borders are measured in pixels. Artifacts appear locally when larger values are used. In the screenshots below, the circle on the right has a size of .3, a fill colour of None and a line width of lineWidth, the value shown above the circles. The circle on the left has a size of .3, a fill colour of white and a grey circle in front of it with a size of .3 - lineWidth / 1000. Note that the overall size of the circle on the r…