# What is the default co-ordinate system in nrrd files saved from Slicer?   

**URL:** <https://discourse.slicer.org/t/what-is-the-default-co-ordinate-system-in-nrrd-files-saved-from-slicer/2719>\
**Category:** Support\
**Created:** [April 27, 2018, 2:43pm UTC](https://discourse.slicer.org/t/what-is-the-default-co-ordinate-system-in-nrrd-files-saved-from-slicer/2719 "2018-04-27T14:43:50Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Krishna\_Nanda](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/krishna_nanda/32/7632_2.png) [@Krishna\_Nanda](https://discourse.slicer.org/u/Krishna_Nanda)\
**Post date:** [April 27, 2018, 2:43pm UTC](https://discourse.slicer.org/t/what-is-the-default-co-ordinate-system-in-nrrd-files-saved-from-slicer/2719/1 "2018-04-27T14:43:50Z")

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Operating system: Windows 7  
Slicer version: 4.8.0  
Expected behavior:  
Actual behavior:

Hello,

I have a quick question about the nrrd files saved from Slicer. Is the default nrrd co-ordinate system LPS? When and how could it be RAS?

Thanks

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [April 27, 2018, 3:33pm UTC](https://discourse.slicer.org/t/what-is-the-default-co-ordinate-system-in-nrrd-files-saved-from-slicer/2719/2 "2018-04-27T15:33:43Z")

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You can look at the ‘space’ field in the nrrd header. Slicer uses ITK, which writes LPS.

The [sourceforge site](http://teem.sf.net/) appears to be down right now, but the unu command should be able to change the space.