# RTX Real Time - Opacity material **URL:** \ **Category:** RTX Renderer\ **Created:** [July 4, 2023, 7:39am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680 "2023-07-04T07:39:41Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![karol.osinski](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/karol.osinski/32/175306_2.png) [@karol.osinski](https://forums.developer.nvidia.com/u/karol.osinski)\ **Post date:** [July 4, 2023, 7:39am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/1 "2023-07-04T07:39:41Z")
Hi, I am trying to make a semi transparent curtain fabric using OmniSurface MTL inside RTX Real Time renderer but changing the opacity down from 100% simply makes the object dissapear. Am I doing something wrong ? Thanks, Karol ---
**Author:** ![toni.sm](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/toni.sm/32/27559_2.png) [@toni.sm](https://forums.developer.nvidia.com/u/toni.sm)\ **Post date:** [July 4, 2023, 8:25am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/2 "2023-07-04T08:25:44Z")
Hi @karol.osinski This post may help: > [@Opacity adjustment not working](https://forums.developer.nvidia.com/t/opacity-adjustment-not-working/231587/7): > > You are using the RTX Realtime mode - there is a cutoff threshold for opacity in this mode, that is set to 1. If you change to path-traced you’ll have the full range of opacity available. To use Opacity in Realtime mode, go to the render settings tab on the right panel, and on Translucency check the “Enable Fractional cutout Opacity”. Results will be subpar, though: Ideally, you should use a translucent material. For best results you should use RTX - Interactive (Path traced) … ---
**Author:** ![karol.osinski](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/karol.osinski/32/175306_2.png) [@karol.osinski](https://forums.developer.nvidia.com/u/karol.osinski)\ **Post date:** [July 4, 2023, 8:36am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/3 "2023-07-04T08:36:15Z")
Hi @toni.sm Thank you for a quick reply! I am aware that PT results are much better but I gotta stick to RealTime renderer for this project. The opacity works now but the white fabric turns to black and my fps instantly went down by like 60%… ![REAL_TIME_OPACITY](https://global.discourse-cdn.com/nvidia/original/4X/2/a/d/2ad5e0db999c1cfe93169172d688380140c58723.jpeg) ---
**Author:** ![toni.sm](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/toni.sm/32/27559_2.png) [@toni.sm](https://forums.developer.nvidia.com/u/toni.sm)\ **Post date:** [July 4, 2023, 8:58am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/4 "2023-07-04T08:58:53Z")
Hi @karol.osinski I have little experience in rendering so let’s look for help. @rgasoto can you please help us with this? * * * By the way, black curtains look amazing!!!.. and provide higher solar protection for this summer 😎 ---
**Author:** ![DavidDPD](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@DavidDPD](https://forums.developer.nvidia.com/u/DavidDPD)\ **Post date:** [September 5, 2023, 8:48am UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/5 "2023-09-05T08:48:53Z")
Hi @karol.osinski , I think this is the setting you’ll need to turn on for partial opacity to work in real time, you can try this out. ![image](https://global.discourse-cdn.com/nvidia/original/4X/e/d/9/ed9b9e9bebff99cf79d5fbb1b4bdab5949b0e540.png) ---
**Author:** ![Richard3D](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/richard3d/32/207062_2.png) [@Richard3D](https://forums.developer.nvidia.com/u/Richard3D)\ **Post date:** [October 16, 2023, 8:06pm UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/6 "2023-10-16T20:06:55Z")
As mentioned, yes you need to enable “Fractional Cutout Opacity” to have partial opacity in RTX realtime. ---
**Author:** ![system](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/system/32/68080_2.png) [@system](https://forums.developer.nvidia.com/u/system)\ **Post date:** [May 16, 2024, 3:30pm UTC](https://forums.developer.nvidia.com/t/rtx-real-time-opacity-material/258680/7 "2024-05-16T15:30:26Z")
Closed on May 16, 2024, 3:30pm UTC This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.