# Disturbing pixel effect when rotating a volume rendering

**URL:** <https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186>\
**Category:** Support\
**Created:** [November 10, 2022, 4:56pm UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186 "2022-11-10T16:56:27Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 10, 2022, 4:56pm UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186/1 "2022-11-10T16:56:27Z")

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What is this pixel effect that you see when rotating a volume rendering with the mouse?  
Can it be avoided?

[https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/c/f/cf17d914149eee0d9f952e81c04b63bd10517cec.mp4](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/c/f/cf17d914149eee0d9f952e81c04b63bd10517cec.mp4)

Thanks.

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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:** [November 10, 2022, 5:11pm UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186/2 "2022-11-10T17:11:47Z")

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That happens when the adaptive mode tries to maintain frames per second while moving.

You can try different options in the Advanced Techniques tab. Maximum will turn off any of the optimizations. Turning on Surface smoothing may also help since those wood grain patterns are due to undersampling of rapid shading changes.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/8/9/8959e37a5869d8c92af608a1ce6edcf0e04ba3ea.png)

Note @rbumm that the scene I sent you the other day has Maximum mode enabled, but if you switch to Normal you see a little less detail but it renders much faster.

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**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 10, 2022, 5:48pm UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186/3 "2022-11-10T17:48:57Z")

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Thank you @pieper I do not see it on my desktop and will check the laptop again tomorrow with different settings.

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [November 10, 2022, 7:53pm UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186/4 "2022-11-10T19:53:32Z")

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Normal usually gives quite good performance even on laptop gpus, unless the scene is very complex.

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**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 11, 2022, 8:10am UTC](https://discourse.slicer.org/t/disturbing-pixel-effect-when-rotating-a-volume-rendering/26186/5 "2022-11-11T08:10:22Z")

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It turns out that on the laptop (Nvidia RTX 1060) setting “Maximum” avoids the wood grain pattern but reduces fps. I’ll probably stick to “Normal”.