# Threshold preview disappearing after clicking "apply"

**URL:** <https://discourse.slicer.org/t/threshold-preview-disappearing-after-clicking-apply/30528>\
**Category:** Support\
**Tags:** segmentation\
**Created:** [July 11, 2023, 7:33pm UTC](https://discourse.slicer.org/t/threshold-preview-disappearing-after-clicking-apply/30528 "2023-07-11T19:33:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Paige\_Mitchell](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/paige_mitchell/32/66746_2.png) [@Paige\_Mitchell](https://discourse.slicer.org/u/Paige_Mitchell)\
**Post date:** [July 11, 2023, 7:33pm UTC](https://discourse.slicer.org/t/threshold-preview-disappearing-after-clicking-apply/30528/1 "2023-07-11T19:33:44Z")

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Hello - I am working on segmenting bones from a CT scan. I have the preview set to the desired threshold range but it all disappears after clicking “apply.” I am working on 3D slicer 5.2.2, all extensions are disabled. I have watched dozens of tutorials, and have yet to find a solution to this issue.

Thanks!

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<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [July 11, 2023, 7:35pm UTC](https://discourse.slicer.org/t/threshold-preview-disappearing-after-clicking-apply/30528/2 "2023-07-11T19:35:40Z")

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Maybe this documentation section will help explaining what’s happening and what to do about it: [Segment editor — 3D Slicer documentation](https://slicer.readthedocs.io/en/latest/user_guide/modules/segmenteditor.html#cannot-paint-outside-some-boundaries)