# Displacement loses negative values when using Image Sequence

**URL:** <https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102>\
**Category:** Issues\
**Created:** [March 28, 2017, 1:15pm UTC](https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102 "2017-03-28T13:15:39Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Magnus\_Olsson](https://avatars.discourse-cdn.com/v4/letter/m/a87d85/32.png) [@Magnus\_Olsson](https://forums.chaos.com/u/Magnus_Olsson)\
**Post date:** [March 28, 2017, 1:15pm UTC](https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102/1 "2017-03-28T13:15:39Z")

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Hi,

I have encountered a problem when trying to use an image sequence as displacement. When I check the Use Image Sequence checkbox the negative values of the displacement no longer works.

I’m using V-Ray 3.40.06 for Maya 2017 Update 3.

I’ve attached a simple scene that demonstrates this.  
[dev\_magnus\_VrayNegativeDisplacementTest\_v001\_mo.ma.zip](https://forums.chaos.com/uploads/short-url/2W3iWIW7xTjoKdRk9EMXSNvyIX6.zip) (8.49 MB)

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**Author:** ![yolov](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/yolov/32/11920_2.png) [@yolov](https://forums.chaos.com/u/yolov)\
**Post date:** [March 29, 2017, 11:36am UTC](https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102/2 "2017-03-29T11:36:12Z")

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You will need to explicitely tell V-Ray the min and max values for displacement bounds. In the V-Ray Displacement node, go to the Displacement control attributes (I see they’re already added in your scene) and change “displacement bounrds” from Auto to Explicit. Then set the Min value to a negative number (for example -1) and the max to a positive (for exapmle +1) or for other textures you might need larger values (-2/2, -5/5).  
The reason you need to set this is that when doing a single texture for displacement, V-Ray is able to read it and automatically define the bounds, but when using a sequence (and/or tiles), V-Ray needs an explicit value.

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<div class="post-metadata">

**Author:** ![Magnus\_Olsson](https://avatars.discourse-cdn.com/v4/letter/m/a87d85/32.png) [@Magnus\_Olsson](https://forums.chaos.com/u/Magnus_Olsson)\
**Post date:** [March 29, 2017, 11:56am UTC](https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102/3 "2017-03-29T11:56:19Z")

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Thanks for your answer Alex. Yes, I read about the “displacement bounds” in the documentation and should have mentioned in my first post that I already tried that. I don’t seem to be able to put a Min value below zero in my scene. Would it be possible for you to test if you can get it to work using my scene?

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**Author:** ![vlado](https://avatars.discourse-cdn.com/v4/letter/v/779978/32.png) [@vlado](https://forums.chaos.com/u/vlado)\
**Post date:** [March 29, 2017, 12:26pm UTC](https://forums.chaos.com/t/displacement-loses-negative-values-when-using-image-sequence/63102/4 "2017-03-29T12:26:06Z")

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> [@Magnus\_Olsson](#):
>
> I don’t seem to be able to put a Min value below zero in my scene.

You need to switch the color picker to RGB 0 to 1 (see attachment).

Best regards,  
Vlado

 ![maya_negative_color.png](https://europe1.discourse-cdn.com/chaosprd/original/3X/c/a/cac14ecbfd7345f4964e5acb5b67db1786b99993.png)