# Landmark registration malfunction

**URL:** <https://discourse.slicer.org/t/landmark-registration-malfunction/14016>\
**Category:** Support\
**Created:** [October 13, 2020, 4:10pm UTC](https://discourse.slicer.org/t/landmark-registration-malfunction/14016 "2020-10-13T16:10:43Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![nvanvuren](https://avatars.discourse-cdn.com/v4/letter/n/edb3f5/32.png) [@nvanvuren](https://discourse.slicer.org/u/nvanvuren)\
**Post date:** [October 13, 2020, 4:10pm UTC](https://discourse.slicer.org/t/landmark-registration-malfunction/14016/1 "2020-10-13T16:10:43Z")

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Hello,

I am using the Landmark Registration module to perform registration of a post mortem ex vivo hemisphere on MRI on a normal brain MRI atlas to correct for the distortion that occurs due to absence of the skull in post mortem ex vivo scanning. As I am using brains with Alzheimer’s disease, the brains show a lot of atrophy and a lot of distortion.

After performing the landmark registration, it looks like this:

 ![Afbeelding1](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/0/5/05d9f38b8a7d13c34f891c7f07542c6612804535.jpeg)

To save the transformed hemisphere, I need to use the Harden transform button. However, when I click it the transformation changes and the registration becomes totally inaccurate.

 ![Afbeelding2](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/5/4/543b5431694ee1c6220a187958e3e9eb4564cf4e.png)

Could you explain what the Harden transform button does exactly? Any ideas how to avoid this change of transformation?