# VrayEnvironmentFog not working with the RTX engine

**URL:** <https://forums.chaos.com/t/vrayenvironmentfog-not-working-with-the-rtx-engine/115816>\
**Category:** Issues\
**Created:** [July 15, 2023, 1:47pm UTC](https://forums.chaos.com/t/vrayenvironmentfog-not-working-with-the-rtx-engine/115816 "2023-07-15T13:47:59Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Alex\_M](https://avatars.discourse-cdn.com/v4/letter/a/77aa72/32.png) [@Alex\_M](https://forums.chaos.com/u/Alex_M)\
**Post date:** [July 15, 2023, 1:47pm UTC](https://forums.chaos.com/t/vrayenvironmentfog-not-working-with-the-rtx-engine/115816/1 "2023-07-15T13:47:59Z")

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Hi,  
I’ve got a scene that I need to use VrayEnvironmentFog with. The fog renders fine with CUDA, but not with RTX. Please see attached the simplified 3ds Max scene and some screenshots.

 ![VrayEnvironmentFog_CUDA.webp](https://europe1.discourse-cdn.com/chaosprd/original/3X/c/c/cc21035879590c527fd44fb80aaea5325e7d6532.webp) ![VrayEnvironmentFog_RTX.webp](https://europe1.discourse-cdn.com/chaosprd/original/3X/7/b/7ba90f6524c6bd57ee289bcbe40a101357581ced.webp)  
[VrayEnvironmentFog\_not\_working\_with\_GPU\_RTX.zip](https://forums.chaos.com/uploads/short-url/4SuUsHdMQe82Lg3KjO07LNgwvR0.zip) (704 KB)

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**Author:** ![tanya\_to](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/tanya_to/32/72991_2.png) [@tanya\_to](https://forums.chaos.com/u/tanya_to)\
**Post date:** [July 24, 2023, 1:04pm UTC](https://forums.chaos.com/t/vrayenvironmentfog-not-working-with-the-rtx-engine/115816/2 "2023-07-24T13:04:53Z")

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Hey @Alex_M ​, I’ve managed to reproduce it and I’ve added it to our bug-tracking system as VGPU-6221. This is caused by the plane objects that are inside the Box gizmo, which is not working as expected with RTX. If you move them outside, RTX should match CUDA.

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<div class="post-metadata">

**Author:** ![Alex\_M](https://avatars.discourse-cdn.com/v4/letter/a/77aa72/32.png) [@Alex\_M](https://forums.chaos.com/u/Alex_M)\
**Post date:** [July 24, 2023, 1:17pm UTC](https://forums.chaos.com/t/vrayenvironmentfog-not-working-with-the-rtx-engine/115816/3 "2023-07-24T13:17:14Z")

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I see. Thanks for logging this!