# Retaining the color of the 2d image used for Volume Rendering.
**URL:** https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230
**Category:** Support
**Created:** [February 22, 2021, 4:19pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230 "2021-02-22T16:19:49Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@Saptarshi\_Paul](https://discourse.vtk.org/u/Saptarshi_Paul)
#### Post date: [February 22, 2021, 4:19pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/1 "2021-02-22T16:19:50Z")
Hello Everyone:
I am very new to volume rendering, and I was able to render a 3d Volume using stack of 2D images in png format. The resultant 3dVolume is in grey scale, but I want the color of the volume to be same as the image. How should I be able to acheive it? Any help or guidance is appreciated.
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### Author:  [@cory.quammen](https://discourse.vtk.org/u/cory.quammen)
#### Post date: [February 22, 2021, 4:27pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/2 "2021-02-22T16:27:42Z")
Welcome to VTK, @Saptarshi_Paul!
In your mapper (`vtkVolumeMapper`?), invoke `SetColorModeToDirectScalars()`. That should avoid the mapping through the gray scale color map.
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### Author:  [@Saptarshi\_Paul](https://discourse.vtk.org/u/Saptarshi_Paul)
#### Post date: [February 22, 2021, 5:04pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/3 "2021-02-22T17:04:17Z")
Hello Cory,
Thank you so much for your help. I am using
volumeMapper = vtk.vtkOpenGLGPUVolumeRayCastMapper(), so how will I be able to invoke SetColorModeToDirectScalars(). I will really appreciate if you can guide me through.
Best Regards
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### Author:  [@lassoan](https://discourse.vtk.org/u/lassoan)
#### Post date: [February 22, 2021, 5:44pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/4 "2021-02-22T17:44:03Z")
For volume rendering, you can use [vtkVolumeProperty::SetIndependentComponents()](https://vtk.org/doc/nightly/html/classvtkVolumeProperty.html#a2534a6dc500be42c9a842d405c4ee0bb).
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### Author:  [@Saptarshi\_Paul](https://discourse.vtk.org/u/Saptarshi_Paul)
#### Post date: [February 22, 2021, 5:49pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/5 "2021-02-22T17:49:44Z")
Hello Andras,
I hope you are doing well. I have already set the SetIndependentComponents(). But it still produces the resultant 3dVolume in grey scale.
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### Author:  [@lassoan](https://discourse.vtk.org/u/lassoan)
#### Post date: [February 22, 2021, 5:52pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/6 "2021-02-22T17:52:54Z")
Probably you don’t have an alpha channel. See details in this topic: [Colored Volume from Tiffstack/MultiImageTiff](https://discourse.vtk.org/t/colored-volume-from-tiffstack-multiimagetiff/4909/7)
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### Author:  [@Saptarshi\_Paul](https://discourse.vtk.org/u/Saptarshi_Paul)
#### Post date: [February 22, 2021, 6:15pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/7 "2021-02-22T18:15:28Z")
Thank you so much Andras, it worked.
I really appreciate your help.
Best Regards
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### Author:  [@cory.quammen](https://discourse.vtk.org/u/cory.quammen)
#### Post date: [February 22, 2021, 6:16pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/8 "2021-02-22T18:16:25Z")
Ah, sorry. I remembered the class hierarchy incorrectly.
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### Author:  [@Saptarshi\_Paul](https://discourse.vtk.org/u/Saptarshi_Paul)
#### Post date: [February 22, 2021, 6:25pm UTC](https://discourse.vtk.org/t/retaining-the-color-of-the-2d-image-used-for-volume-rendering/5230/9 "2021-02-22T18:25:34Z")
Thank you Cory, I really appreciate your help.
Best Regards