Blender saves out what appears to be a blank image of emission volumes when background transparency is enabled. #100983

New Issue

Dan · 2022-09-11T17:15:28+02:00

Dan commented

2022-09-11 17:15:28 +02:00

System Information
Operating system: Windows 11
Graphics card: nVidia RTX 3060

Blender Version
Broken: 3.3.0, 3.2.1

Short description of error
When saving an image of an emission volume with a transparent background, Blender renders the image properly, but appears to save out an image of nothing.

Exact steps for others to reproduce the error
From default startup: In the material of the default cube, remove the principled shader and add an emission shader connected to the volume input of the material output. Then, in either EEVEE or Cycles settings (both share this problem) turn on background transparency in the render properties under film. Render an image and save it out as a png file with RGBA enabled. The file when viewed in other software and even in Blender's own image editor will appear to be blank, though the image WILL appear in Blender's compositor via an image node. So the image works, just not as a user may expect it to or find useful.

Sorry if this is expected behavior.

**System Information** Operating system: Windows 11 Graphics card: nVidia RTX 3060 **Blender Version** Broken: 3.3.0, 3.2.1 **Short description of error** When saving an image of an emission volume with a transparent background, Blender renders the image properly, but appears to save out an image of nothing. **Exact steps for others to reproduce the error** From default startup: In the material of the default cube, remove the principled shader and add an emission shader connected to the volume input of the material output. Then, in either EEVEE or Cycles settings (both share this problem) turn on background transparency in the render properties under film. Render an image and save it out as a png file with RGBA enabled. The file when viewed in other software and even in Blender's own image editor will appear to be blank, though the image WILL appear in Blender's compositor via an image node. So the image works, just not as a user may expect it to or find useful. Sorry if this is expected behavior.

Dan commented

2022-09-11 17:15:28 +02:00

Added subscriber: @DoNotCare

Omar Emara commented

2022-09-12 14:50:04 +02:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-09-12 14:50:04 +02:00

This is expected, as saving the image as PNG automatically premultiplies the alpha of the render, which is zero everywhere, so the final image becomes zero. This is already reported many time before, so I will merge to one of those reports.

Omar Emara commented

2022-09-12 14:50:12 +02:00

Closed as duplicate of #81199

Omar Emara closed this issue

2022-09-12 14:50:12 +02:00

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Blender saves out what appears to be a blank image of emission volumes when background transparency is enabled. #100983