# Surface opacity jump
**URL:** https://discourse.slicer.org/t/surface-opacity-jump/8384
**Category:** Support
**Created:** [September 11, 2019, 3:44pm UTC](https://discourse.slicer.org/t/surface-opacity-jump/8384 "2019-09-11T15:44:16Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@rprueckl](https://discourse.slicer.org/u/rprueckl)
#### Post date: [September 11, 2019, 3:44pm UTC](https://discourse.slicer.org/t/surface-opacity-jump/8384/1 "2019-09-11T15:44:16Z")
When changing the opacity of a surface, the first step from fully opaque to ‘just a little transparent’ (i.e. from 1.00 to 0.99) causes a relatively big visual difference, whereas the change from 0.99 to 0.98 causes no visible difference. I was looking at a model of the skull generated from the CT of the ‘CT-MR Brain’ sample dataset.
I wonder whether there is a possibility to make the transition between fully opaque and ‘a bit transparent’ smoother?
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### Author:  [@pieper](https://discourse.slicer.org/u/pieper)
#### Post date: [September 11, 2019, 7:16pm UTC](https://discourse.slicer.org/t/surface-opacity-jump/8384/2 "2019-09-11T19:16:18Z")
If your model has a lot of internal structure then you may need to enable depth peeling in order to get predictable rendering.
[https://www.slicer.org/wiki/Documentation/4.3/SlicerApplication/MainApplicationGUI#3D\_Viewer](https://www.slicer.org/wiki/Documentation/4.3/SlicerApplication/MainApplicationGUI#3D_Viewer)