# 3D Surface Contour - Extract Selection

**URL:** https://discourse.paraview.org/t/3d-surface-contour-extract-selection/9893
**Category:** ParaView Support
**Created:** [June 23, 2022, 11:42am UTC](https://discourse.paraview.org/t/3d-surface-contour-extract-selection/9893 "2022-06-23T11:42:04Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Akash](https://discourse.paraview.org/user_avatar/discourse.paraview.org/akash/32/6994_2.png) [@Akash](https://discourse.paraview.org/u/Akash)
#### Post date: [June 23, 2022, 11:42am UTC](https://discourse.paraview.org/t/3d-surface-contour-extract-selection/9893/1 "2022-06-23T11:42:04Z")

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Hi,  
I am trying to extract coherent structures with alpha \>= 0.5. But I am getting those 3D surfaces disrupted as you can see in the fig I attached. I understand why it’s happening, its because some of the grid points might not satisfy the extraction condition. Is there a way to fix it or any other approach to extract those 3D surfaces?  
Thank you for the help!

 ![Screenshot 2022-06-19 094051](https://discourse.paraview.org/uploads/default/original/2X/8/8ce11cd411e55bfb06f930d751ad3d5e014288e6.jpeg)

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### Author: ![Kenichiro-Yoshimi](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/k/ecc23a/32.png) [@Kenichiro-Yoshimi](https://discourse.paraview.org/u/Kenichiro-Yoshimi)
#### Post date: [June 25, 2022, 4:25am UTC](https://discourse.paraview.org/t/3d-surface-contour-extract-selection/9893/2 "2022-06-25T04:25:10Z")

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Hi,

It may be adjusted in the **All Scalars** option of the **Threshold** filter.