# Landmark registration overlay not showing up

**URL:** https://discourse.slicer.org/t/landmark-registration-overlay-not-showing-up/45965
**Category:** Support
**Tags:** registration
**Created:** [January 28, 2026, 9:14am UTC](https://discourse.slicer.org/t/landmark-registration-overlay-not-showing-up/45965 "2026-01-28T09:14:58Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![RHB](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rhb/32/78664_2.png) [@RHB](https://discourse.slicer.org/u/RHB)
#### Post date: [January 28, 2026, 9:14am UTC](https://discourse.slicer.org/t/landmark-registration-overlay-not-showing-up/45965/1 "2026-01-28T09:14:58Z")

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Hi,  
I have 2 2D oct slices that I want to register mutually, these are not 3D volume, just retinal 2D slice and previously I tried to do Landmark registration using these, it worked. Now after that I am trying to do the same thing but sometimes the overlay shows up sometimes doesn’t. Basically without the overlapping slices, I can’t put marker on the slices and transform. Any idea why this is happening? ss attached below.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/4/d/4dfd7ba867004d21fb1a4ab963538d0282d6146e.jpeg)

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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: [January 28, 2026, 12:40pm UTC](https://discourse.slicer.org/t/landmark-registration-overlay-not-showing-up/45965/2 "2026-01-28T12:40:39Z")

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Sometimes you need to use the Fit button to make sure the views are set correctly. If that’s not it, maybe you can determine a minimal set of operations to replicate the issue so someone can replicate it.

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<div class="post-metadata">

### Author: ![RHB](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rhb/32/78664_2.png) [@RHB](https://discourse.slicer.org/u/RHB)
#### Post date: [January 28, 2026, 3:25pm UTC](https://discourse.slicer.org/t/landmark-registration-overlay-not-showing-up/45965/3 "2026-01-28T15:25:02Z")

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I got it worked afterwards. The problem is during data loading, only need to set the moving and fixed volume and nothing else. Although there are options to set output/ **transformed volume** and **target transform** name, if I set those up, overlaping windows stays black no matter what I try. So only load fixed volume and moving volume, set the registration type and later set the output/transformation name.