# What is the default center of rotation for an Euler3DTransform?

**URL:** <https://discourse.itk.org/t/what-is-the-default-center-of-rotation-for-an-euler3dtransform/7677>\
**Category:** Uncategorized\
**Created:** [December 6, 2025, 8:01pm UTC](https://discourse.itk.org/t/what-is-the-default-center-of-rotation-for-an-euler3dtransform/7677 "2025-12-06T20:01:47Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![gdevenyi](https://discourse.itk.org/user_avatar/discourse.itk.org/gdevenyi/32/355_2.png) [@gdevenyi](https://discourse.itk.org/u/gdevenyi)\
**Post date:** [December 6, 2025, 8:01pm UTC](https://discourse.itk.org/t/what-is-the-default-center-of-rotation-for-an-euler3dtransform/7677/1 "2025-12-06T20:01:47Z")

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If i do not use a transform initializer for a registration, what will be the center of rotation?

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**Author:** ![zivy](https://discourse.itk.org/user_avatar/discourse.itk.org/zivy/32/1726_2.png) [@zivy](https://discourse.itk.org/u/zivy)\
**Post date:** [December 7, 2025, 2:27pm UTC](https://discourse.itk.org/t/what-is-the-default-center-of-rotation-for-an-euler3dtransform/7677/2 "2025-12-07T14:27:34Z")

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Hi @gdevenyi,

When you create the transform without setting any value the default center is `[0,0,0]`. The [fixed transform parameters are filled with zeros](https://github.com/InsightSoftwareConsortium/ITK/blob/0fa82fb49f2a3bf3bb7666bb93a10610b73f1684/Modules/Core/Transform/include/itkEuler3DTransform.hxx#L32) in the constructor.

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**Author:** ![gdevenyi](https://discourse.itk.org/user_avatar/discourse.itk.org/gdevenyi/32/355_2.png) [@gdevenyi](https://discourse.itk.org/u/gdevenyi)\
**Post date:** [December 7, 2025, 4:33pm UTC](https://discourse.itk.org/t/what-is-the-default-center-of-rotation-for-an-euler3dtransform/7677/3 "2025-12-07T16:33:24Z")

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Thanks, I couldn’t find the details in the docs.