# Problems with Stereo Rendering on MacOS with Qt UI

**URL:** https://discourse.vtk.org/t/problems-with-stereo-rendering-on-macos-with-qt-ui/4902
**Category:** Support
**Created:** [December 27, 2020, 2:49pm UTC](https://discourse.vtk.org/t/problems-with-stereo-rendering-on-macos-with-qt-ui/4902 "2020-12-27T14:49:42Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![TheAmazingDurp](https://discourse.vtk.org/user_avatar/discourse.vtk.org/theamazingdurp/32/2792_2.png) [@TheAmazingDurp](https://discourse.vtk.org/u/TheAmazingDurp)
#### Post date: [December 27, 2020, 2:49pm UTC](https://discourse.vtk.org/t/problems-with-stereo-rendering-on-macos-with-qt-ui/4902/1 "2020-12-27T14:49:42Z")

</div>

So for the past 3 weeks I have been able to use Stereo Rendering on my Macbook running Catalina. However, some days ago it started acting up and whenever I use it with a button click it doesn’t render in the Qt frame but instead it opens up a Cocoa window with the render on it. But the interactions still work on the frame and new Cocoa window. When removing “self.vtk\_widget.GetRenderWindow().Finalize()” it works as it should but gives the following error message “Requesting a StereoCapableWindow must be performed before the window is realized, i.e. before a render.”

This is how it should look:

 ![133767706_1112424862512412_2002721827792653757_n](https://discourse.vtk.org/uploads/default/original/2X/4/4cd622a62141e7e7013e82f0c0b925a2aeb1a807.jpeg)

But this is how it looks instead:

 ![133720304_226785315723637_8946736511579132716_n](https://discourse.vtk.org/uploads/default/original/2X/f/f8899773865b2385373d9dfa5f57104455653cd1.jpeg)

```
self.vtk_widget.GetRenderWindow().Finalize() 
self.vtk_widget.GetRenderWindow().StereoCapableWindowOn()
self.vtk_widget.GetRenderWindow().SetStereoRender(1)
self.vtk_widget.GetRenderWindow().SetStereoTypeToAnaglyph()
self.vtk_widget.GetRenderWindow().StereoRenderOn()
```