Render window black background

I’ve got another glitch with iray in Rhino 7.5. The background displays black in the render window, the saved files are fine.

Hi @JimCarruthers,

Are you rendering with a transparent background? If so, when previewing the render in the render window make sure you show all color channels, including the alpha channel.


Hope this helps,

Yes I’m rendering with a transparent background–usually with a wallpaper backdrop, but it shows the issue with or without it. Yes I’m showing all channels, there is no setting that shows the background correctly. The iray viewport and the saved renders show the background.

Hey James, can you run the systeminfo command in rhino and post the results?

also can you post a screen shot showing the issue and may the file as well-

Here we are…the saved render file does have the background.

Rhino 7 SR6 2021-5-7 (Rhino 7, 7.6.21127.19001, Git hash:master @ aec74c050f3ca28ab3cfd6882e9453a52366a9b7)
License type: Not For Resale Lab, build 2021-05-07
License details: Cloud Zoo

Windows 10.0.19041 SR0.0 or greater (Physical RAM: 64Gb)

Computer platform: DESKTOP

Standard graphics configuration.
Primary display and OpenGL: NVIDIA GeForce GTX 1080 Ti (NVidia) Memory: 11GB, Driver date: 5-13-2021 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 466.47
> Accelerated graphics device with 4 adapter port(s)
- Windows Main Display attached to adapter port #0
- Secondary monitor attached to adapter port #1

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: High

Vendor Name: NVIDIA Corporation
Render version: 4.6
Shading Language: 4.60 NVIDIA
Driver Date: 5-13-2021
Driver Version:
Maximum Texture size: 32768 x 32768
Z-Buffer depth: 24 bits
Maximum Viewport size: 32768 x 32768
Total Video Memory: 11 GB

Rhino plugins that do not ship with Rhino
C:\Program Files\Bongo 2.0 (64-bit)\Rhino6\Bongo.20.rhp “Bongo 2.0”
C:\Users\James Carruthers\Downloads\Rhino_6_Win_2018.1130\HDRLightStudioTexture.rhp “HDRLightStudioTexture”
C:\Program Files\Common Files\McNeel\Rhinoceros\7.0\Plug-ins\Iray (6ac73cf3-0a75-45a4-a5a1-89e40bc53c4b)\1.5.404.0\6\IrayRhino.Plugin.rhp “Iray” 1.5.404.0
C:\Users\James Carruthers\AppData\Roaming\McNeel\Rhinoceros\packages\7.0\NVIDIADenoiser\0.4.0\NVIDIADenoiser.Windows.rhp “NVIDIADenoiser.Windows”

Rhino plugins that ship with Rhino
C:\Program Files\Rhino 7\Plug-ins\Commands.rhp “Commands” 7.6.21127.19001
C:\Program Files\Rhino 7\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 7\Plug-ins\RhinoScript.rhp “RhinoScript”
C:\Program Files\Rhino 7\Plug-ins\RPC.rhp “RPC”
C:\Program Files\Rhino 7\Plug-ins\AnimationTools.rhp “AnimationTools”
C:\Program Files\Rhino 7\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 7.6.21127.19001
C:\Program Files\Rhino 7\Plug-ins\RhinoRender.rhp “Legacy Rhino Render”
C:\Program Files\Rhino 7\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 7.6.21127.19001
C:\Program Files\Rhino 7\Plug-ins\rdk_ui.rhp “Renderer Development Kit UI”
C:\Program Files\Rhino 7\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino 7\Plug-ins\RhinoCycles.rhp “RhinoCycles” 7.6.21127.19001
C:\Program Files\Rhino 7\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 7.6.21127.19001
C:\Program Files\Rhino 7\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 7\Plug-ins\Displacement.rhp “Displacement”
C:\Users\James Carruthers\AppData\Roaming\McNeel\Rhinoceros\packages\7.0\PanelingTools\2021.3.2.446\PanelingTools.rhp “PanelingTools”

Render backdrop test.3dm (538.4 KB)

Hi @JimCarruthers,

I’m afraid I’m unable to reproduce the issue using your exact Rhino version.

The file that you attached didn’t seem to include the wallpaper image. In addition to that, the Rendering settings haven’t been set to use the wallpaper as a backdrop, so even if the image was included it would not have shown up in the rendering.

Did you send the exact file that is shown in your screen shot?


The wallpaper setting has no impact on the issue. Yes I sent the actual file. Are you using iRay?

@JimCarruthers, Sorry I was mixing up some facts with another thread I was just reading. I wasn’t testing with iRay. I will try to give it a go.



I see the problem and a fix is going into Rhino 7.7 (Service Release Candidate). The fix will hopefully be available in a couple of days.

Thank you for reporting this!