# Creating actors after vtkImageBlend

**URL:** https://discourse.vtk.org/t/creating-actors-after-vtkimageblend/7434
**Category:** Support
**Created:** [December 19, 2021, 2:06pm UTC](https://discourse.vtk.org/t/creating-actors-after-vtkimageblend/7434 "2021-12-19T14:06:39Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Valentin\_Regueiro](https://discourse.vtk.org/user_avatar/discourse.vtk.org/valentin_regueiro/32/4419_2.png) [@Valentin\_Regueiro](https://discourse.vtk.org/u/Valentin_Regueiro)
#### Post date: [December 19, 2021, 2:06pm UTC](https://discourse.vtk.org/t/creating-actors-after-vtkimageblend/7434/1 "2021-12-19T14:06:39Z")

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Hello everyone,

first of all I’m a noob trying to learn VTK so excuse me if the question seems unnecessary. I can not find an answer anywhere.

Right now I am getting vtkImageData from nifti Images, which is passed through a vtkImageMapToColors, then through vtkImageBlend which is connected to a vtkImageViewer2. I tried connecting vtkImageBlend to a vtkPolyDataMapper and the OutputPort to the viewer, but apparently there is no output port and the viewer won’t work without an input connection.

My question is; how can I create actors of the volumes (and where?) so that those are pickable through the slice viewer? I seem to be confused about what exactly is a mapper here, since the vtkImageMapToColors is connected to the vtkImageBlend, and not to the rendering pipeline.

Thanks a lot for your time. Any help is greatly appreciated.  
Best regards, Valentin.

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### Author: ![mwestphal](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mwestphal/32/19_2.png) [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [December 31, 2021, 9:58am UTC](https://discourse.vtk.org/t/creating-actors-after-vtkimageblend/7434/2 "2021-12-31T09:58:43Z")

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you will have to show some code of what you tried