Camera Background image is appearing greyish in 3D Viewport #99507

New Issue

Rakesh Dey · 2022-07-07T02:50:48+02:00

Rakesh Dey commented

2022-07-07 02:50:48 +02:00

System Information
Operating system: Windows 10
Graphics card: Nvidia GTX 1080Ti

Blender Version 3.2.1
Broken: version: 3.2.1, branch: master, commit date: 2022-07-05 15:44, hash: a2d59b2dac
Worked:

Short description of error
Camera Background image is appearing greyish in deep black area in 3D Viewport but showing completely normal in Image editor section and renders.
Even after turning on "View as Render", problem is still there.

Exact steps for others to reproduce the error
Open the attached blend file.Blender BG Bug Report.blend

**System Information** Operating system: Windows 10 Graphics card: Nvidia GTX 1080Ti **Blender Version** 3.2.1 Broken: version: 3.2.1, branch: master, commit date: 2022-07-05 15:44, hash: a2d59b2dac9e Worked: **Short description of error** Camera Background image is appearing greyish in deep black area in 3D Viewport but showing completely normal in Image editor section and renders. Even after turning on "View as Render", problem is still there. **Exact steps for others to reproduce the error** Open the attached blend file.[Blender BG Bug Report.blend](https://archive.blender.org/developer/F13265208/Blender_BG_Bug_Report.blend)

Rakesh Dey commented

2022-07-07 02:50:48 +02:00

Added subscriber: @RakeshDey

Rakesh Dey commented

2022-07-07 02:52:42 +02:00

Here's a long post I wrote on reddit on it - https://www.reddit.com/r/blender/comments/vs0e6n/why_is_the_camera_background_image_appearing

Pratik Borhade commented

2022-07-07 06:28:18 +02:00

Added subscriber: @PratikPB2123

Pratik Borhade commented

2022-07-07 06:28:18 +02:00

Thanks for the report. Enabling View as render may solve the issue. Can you try it?

(I'm not sure about the use cases of this option)

Thanks for the report. Enabling [View as render ](https://docs.blender.org/manual/en/3.2/editors/image/image_settings.html#bpy-types-image-use-view-as-render) may solve the issue. Can you try it? (I'm not sure about the use cases of this option)

Omar Emara commented

2022-07-07 08:45:27 +02:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-07-07 08:45:27 +02:00

Could be the same as #98024.

Pratik Borhade commented

2022-07-07 08:52:55 +02:00

@OmarEmaraDev, feel free to merge if you think so or just change to need info from user until Rakesh's confirmation

@OmarEmaraDev, feel free to merge if you think so or just change to `need info from user` until Rakesh's confirmation

Omar Emara commented

2022-07-07 08:55:06 +02:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Omar Emara commented

2022-07-07 08:55:06 +02:00

@PratikPB2123 Not sure yet if it is the same, but it links to the commits/tasks explaining the rational behind the View As Render option, so I thought I would link it. I will change to need info for now.

Rakesh Dey commented

2022-07-07 10:40:12 +02:00

In #99507#1386728, @PratikPB2123 wrote:
Thanks for the report. Enabling View as render may solve the issue. Can you try it?

(I'm not sure about the use cases of this option)

Yes I enabled it. Still having same issue. I also updated the description and the attached file with this option turned on.

> In #99507#1386728, @PratikPB2123 wrote: > Thanks for the report. Enabling [View as render ](https://docs.blender.org/manual/en/3.2/editors/image/image_settings.html#bpy-types-image-use-view-as-render) may solve the issue. Can you try it? > > (I'm not sure about the use cases of this option) Yes I enabled it. Still having same issue. I also updated the description and the attached file with this option turned on.

Omar Emara commented

2022-07-07 11:30:48 +02:00

Changed status from 'Needs User Info' to: 'Needs Developer To Reproduce'

Omar Emara commented

2022-07-07 11:30:48 +02:00

I can confirm the difference. It seems the two values before color management are 0.00281 and 0.00273. And as far as I can tell, this is due to the use of different texture types, one uses R16G16B16A16_FLOAT and the other uses R8G8B8A8_SRGB. I am not sure what that entails exactly, so will wait for information from developers.

I can confirm the difference. It seems the two values before color management are `0.00281` and `0.00273`. And as far as I can tell, this is due to the use of different texture types, one uses `R16G16B16A16_FLOAT` and the other uses `R8G8B8A8_SRGB`. I am not sure what that entails exactly, so will wait for information from developers.

Rakesh Dey commented

2022-07-07 13:18:26 +02:00

In #99507#1386893, @OmarEmaraDev wrote:
I can confirm the difference. It seems the two values before color management are 0.00281 and 0.00273. And as far as I can tell, this is due to the use of different texture types, one uses R16G16B16A16_FLOAT and the other uses R8G8B8A8_SRGB. I am not sure what that entails exactly, so will wait for information from developers.

Nope. Different bit depth isn't the reason here. I have update the attached blend file with 8bit jpg. The bug is still there.

> In #99507#1386893, @OmarEmaraDev wrote: > I can confirm the difference. It seems the two values before color management are `0.00281` and `0.00273`. And as far as I can tell, this is due to the use of different texture types, one uses `R16G16B16A16_FLOAT` and the other uses `R8G8B8A8_SRGB`. I am not sure what that entails exactly, so will wait for information from developers. Nope. Different bit depth isn't the reason here. I have update the attached blend file with 8bit jpg. The bug is still there.

Omar Emara commented

2022-07-07 13:22:32 +02:00

I was talking about the GPU textures used internally by Blender, not the images themselves. And the difference is not only in bit-depth, it is also in the fact that one uses sRGB storage.

Rakesh Dey commented

2022-07-07 13:32:54 +02:00

In #99507#1386940, @OmarEmaraDev wrote:
I was talking about the GPU textures used internally by Blender, not the images themselves. And the difference is not only in bit-depth, it is also in the fact that one uses sRGB storage.

Oh I didn't think about it that deeply. Anyways let's wait for more info from developers.

> In #99507#1386940, @OmarEmaraDev wrote: > I was talking about the GPU textures used internally by Blender, not the images themselves. And the difference is not only in bit-depth, it is also in the fact that one uses sRGB storage. Oh I didn't think about it that deeply. Anyways let's wait for more info from developers.

Campbell Barton commented

2022-07-08 02:22:26 +02:00

Added subscribers: @fclem, @Sergey, @ideasman42

Campbell Barton commented

2022-07-08 02:22:26 +02:00

As far as I can see the 3D viewport and the image display use slightly different color management transforms.

Even if this isn't technically a bug, it should be straightforward to have them match - looking into this I wasn't able to make them match.

@fclem / @Sergey - are you aware of this issue or possible solutions?

As far as I can see the 3D viewport and the image display use slightly different color management transforms. Even if this isn't technically a bug, it should be straightforward to have them match - looking into this I wasn't able to make them match. @fclem / @Sergey - are you aware of this issue or possible solutions?

Sergey Sharybin commented

2022-07-08 09:42:50 +02:00

This isn't my area, so can not comment from the code perspective.

To me it seems that there is a bug somewhere in the viewport. The view transform is Standard, the Look is None, gamma and exposure are default. Toggling "View as Render" should not make image look different. This is the behavior in the Image Editor, but not in the viewport. I do not know where the extra gamma correction is coming from there.

This isn't my area, so can not comment from the code perspective. To me it seems that there is a bug somewhere in the viewport. The view transform is Standard, the Look is None, gamma and exposure are default. Toggling "View as Render" should not make image look different. This is the behavior in the Image Editor, but not in the viewport. I do not know where the extra gamma correction is coming from there.

Clément Foucault commented

2022-07-08 12:14:28 +02:00

I can't see the difference by just looking at it. Maybe the difference is due to the way the sRGB render target differs for each implementation, but I highly doubt.

Top: viewpor
Bottom: image editor

I can't see the difference by just looking at it. Maybe the difference is due to the way the sRGB render target differs for each implementation, but I highly doubt. ![Screenshot from 2022-07-08 12-11-55.png](https://archive.blender.org/developer/F13271342/Screenshot_from_2022-07-08_12-11-55.png) Top: viewpor Bottom: image editor

Omar Emara commented

2022-07-08 12:45:43 +02:00

In #99507#1386893, @OmarEmaraDev wrote:
I can confirm the difference. It seems the two values before color management are 0.00281 and 0.00273. And as far as I can tell, this is due to the use of different texture types, one uses R16G16B16A16_FLOAT and the other uses R8G8B8A8_SRGB. I am not sure what that entails exactly, so will wait for information from developers.

@fclem Could it be explained through that?

> In #99507#1386893, @OmarEmaraDev wrote: > I can confirm the difference. It seems the two values before color management are `0.00281` and `0.00273`. And as far as I can tell, this is due to the use of different texture types, one uses `R16G16B16A16_FLOAT` and the other uses `R8G8B8A8_SRGB`. I am not sure what that entails exactly, so will wait for information from developers. @fclem Could it be explained through that?

Clément Foucault commented

2022-07-08 18:42:40 +02:00

@OmarEmaraDev The source image should be the same GPUTexture to my knowledge. But yes, the camera Background is rendered to a R8G8B8A8_SRGB framebuffer and the Image Editor image to a R16G16B16A16_FLOAT buffer before display transform is applied. This intermediate step might result in this imprecision which is really low. I'm guessing that this is visible on good HDR screens but here the difference is not noticeable.

@OmarEmaraDev The source image should be the same GPUTexture to my knowledge. But yes, the camera Background is rendered to a `R8G8B8A8_SRGB` framebuffer and the Image Editor image to a `R16G16B16A16_FLOAT` buffer before display transform is applied. This intermediate step might result in this imprecision which is really low. I'm guessing that this is visible on good HDR screens but here the difference is not noticeable.

Rakesh Dey commented

2022-07-09 13:47:44 +02:00

In #99507#1387809, @fclem wrote:
@OmarEmaraDev The source image should be the same GPUTexture to my knowledge. But yes, the camera Background is rendered to a R8G8B8A8_SRGB framebuffer and the Image Editor image to a R16G16B16A16_FLOAT buffer before display transform is applied. This intermediate step might result in this imprecision which is really low. I'm guessing that this is visible on good HDR screens but here the difference is not noticeable.

It is visible in both my pro hdr monitor and a cheap sRGB 99% colour accurate monitor. Even though the difference is tiny still it catches my eye every time I use Gradient background images and it looks bad while previewing darker objects in front of it.

> In #99507#1387809, @fclem wrote: > @OmarEmaraDev The source image should be the same GPUTexture to my knowledge. But yes, the camera Background is rendered to a `R8G8B8A8_SRGB` framebuffer and the Image Editor image to a `R16G16B16A16_FLOAT` buffer before display transform is applied. This intermediate step might result in this imprecision which is really low. I'm guessing that this is visible on good HDR screens but here the difference is not noticeable. It is visible in both my pro hdr monitor and a cheap sRGB 99% colour accurate monitor. Even though the difference is tiny still it catches my eye every time I use Gradient background images and it looks bad while previewing darker objects in front of it.

Clément Foucault commented

2022-07-09 15:29:55 +02:00

Added subscriber: @Jeroen-Bakker

Clément Foucault commented

2022-07-09 15:29:55 +02:00

I can clearly see the difference on my MacBook Pro M1.

And I can see it changing when updating the 3D view (can playback animation to see the effect). And it does not appear in material preview shading mode. So I am guessing this has to do with Workbench TAA not accumulating to exact opacity level. EEVEE also had this issue and I had to add a special case if alpha was near 1.0 to round it to 1.0.

@Jeroen-Bakker Could you take over this?

I can clearly see the difference on my MacBook Pro `M1`. ![Capture d’écran 2022-07-09 à 15.10.32.png](https://archive.blender.org/developer/F13279310/Capture_d_e_cran_2022-07-09_a__15.10.32.png) And I can see it changing when updating the 3D view (can playback animation to see the effect). And it does not appear in material preview shading mode. So I am guessing this has to do with Workbench TAA not accumulating to exact opacity level. EEVEE also had this issue and I had to add a special case if alpha was near 1.0 to round it to 1.0. @Jeroen-Bakker Could you take over this?

Clément Foucault commented

2022-07-09 15:30:21 +02:00

Changed status from 'Needs Developer To Reproduce' to: 'Confirmed'

Jeroen Bakker self-assigned this 2022-07-10 10:22:01 +02:00

Philipp Oeser removed the

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Camera Background image is appearing greyish in 3D Viewport #99507