# Problems After nrrd Export

**URL:** <https://discourse.slicer.org/t/problems-after-nrrd-export/36356>\
**Category:** Support\
**Tags:** segmentation, dicom, 3d-model, segmentations, segment-editor\
**Created:** [May 23, 2024, 7:49pm UTC](https://discourse.slicer.org/t/problems-after-nrrd-export/36356 "2024-05-23T19:49:56Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![berke6](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@berke6](https://discourse.slicer.org/u/berke6)\
**Post date:** [May 23, 2024, 7:49pm UTC](https://discourse.slicer.org/t/problems-after-nrrd-export/36356/1 "2024-05-23T19:49:56Z")

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Hello,  
I am very new to 3D Slicer. I started using it to 3D render the series of labeled DICOM files I have. It does a fascinating job in rendering them, and using the Segmentation Editor, I can give different colors to different labels. However, the problem starts after I try to export this 3D rendering.

When I tried to export it in the STL format, the file has a size greater than 1 GB. Hence, I tried the nrrd and nii formats. However, I experienced a couple of problems

1. When I import the file back, the quality in 3D seems to be decreased a lot. Why would that happen?
2. The colors I assign in the Segment Editor seems to be lost. Is there a way to preserve these colors?
3. I cannot find a way to set opacity. I looked at many other discussions, and although I can control the opacity in the 3D rendering made from DICOMs, I could not find a way to do it in the imported nrrd file.

I would greatly appreciate your guidance and support on any of these problems I have encountered.

Thanks,  
Berke