# In Segment Editor module some parts can not be marked

**URL:** <https://discourse.slicer.org/t/in-segment-editor-module-some-parts-can-not-be-marked/14624>\
**Category:** Support\
**Created:** [November 16, 2020, 2:57am UTC](https://discourse.slicer.org/t/in-segment-editor-module-some-parts-can-not-be-marked/14624 "2020-11-16T02:57:23Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Aitekk](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aitekk/32/7890_2.png) [@Aitekk](https://discourse.slicer.org/u/Aitekk)\
**Post date:** [November 16, 2020, 2:57am UTC](https://discourse.slicer.org/t/in-segment-editor-module-some-parts-can-not-be-marked/14624/1 "2020-11-16T02:57:23Z")

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In Segment Editor module, the editable area of the volume is smaller than the whole volume, which makes some parts can not be marked

Operating system:Windows 10  
Slicer version:4.11  
Expected behavior:The whole volume should be editable by Paint tool.  
Actual behavior:The editable area of the volume is smaller than the whole volume. In fact, I’m limited to a local area when I’m tagging with the Paint tool, which prevents me from getting the desired segment (as shown in the videos and images below). that’s strange. I would appreciate for the help.

![ezgif.com-crop](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/d/f/df5c3182ce005f8f018277e5a109305ffa41ef46.gif)

 ![16054953982449](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/b/f/bff3e5e18353cb7eb079f70885db497cbbd3fc03.jpeg)

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**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:** [November 16, 2020, 7:20am UTC](https://discourse.slicer.org/t/in-segment-editor-module-some-parts-can-not-be-marked/14624/2 "2020-11-16T07:20:37Z")

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Resolution and extent of the segmentation is determined by the first selected master volume. The simplest is to choose the first master volume to be the volume that you will use later for segmentation, but you can change the extent anytime (by clicking on the [“Specify geometry” button in Segment Editor](https://slicer.readthedocs.io/en/latest/user_guide/modules/segmenteditor.html#panels-and-their-use) and choose volume or ROI node).

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**Author:** ![Aitekk](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aitekk/32/7890_2.png) [@Aitekk](https://discourse.slicer.org/u/Aitekk)\
**Post date:** [November 17, 2020, 2:21am UTC](https://discourse.slicer.org/t/in-segment-editor-module-some-parts-can-not-be-marked/14624/3 "2020-11-17T02:21:33Z")

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I tried as you suggested, and it worked well. Thanks much for your help!