srg and linear srg options reversed Tweet

[boxfx]

Still the same problem.

Fresh install of c4d R25
Fresh install of octane 2021.1 R2
Fresh scene file made 100% in the new versions, so no legacy problems

Rendering out to 8 or 16 bit 0-255 formats (png in my tests) with a straight alpha gives washed out renders. The alpha channel type is still affecting the rendering/saving colour space/gamma

[aoktar]

You're talking about something which is not in my control. Probably C4D is applying a color management in case and assuming that's linear color space. Then you can change to "linear color space" in octane settings to get correct outputs.

[boxfx]

You're talking about something which is not in my control. Probably C4D is applying a color management in case and assuming that's linear color space. Then you can change to "linear color space" in octane settings to get correct outputs.

Not in your control because something changed in C4D or something changed in Octane render? We're talking about every version of C4D from R15 to R25, so this isn't a C4D change. This only started happening since 2020.2.4; previous versions of octane dint have this problem.

If I switch the Linear response under the camera imager then the external renders are correct, but now my octane live view renders everything too dark.

We're really not asking for the world here. We want to render a standard 8bit image in srgb space with a straight alpha, and to have the preview window match the render output. We've been successfully doing this in octane for years right up until 2020.2.4 came along and changed something. Maybe we're doing something wrong, we're not perfect. If we have missed a switch, or pressed a wrong button somewhere, please let us know.

Can you or anyone else here accomplish this basic task? Render an 8bit srgb png file with a straight alpha, and have the rendered result match what you saw in the live viewer?

[aoktar]

Things may not change since versions but behavior is same and there are not more to do on my side. How can say it better don't know! Also I said what to do in my answer. Read again please.

[elsksa]

Hi,
If the output referred rasterized image file does look "washed out", it is likely caused by "a double sRGB EOTF" (mistakenly known as "gamma"). For more information, https://www.elsksa.me/scientia/cgi-offline-rendering/cgi-color-management-survival-kit

In regard to PNG, I would strongly suggest this quick read: https://www.elsksa.me/scientia/cgi-offline-rendering/file-format-debunk

[boxfx]

Hi,
If the output referred rasterized image file does look "washed out", it is likely caused by "a double sRGB EOTF" (mistakenly known as "gamma"). For more information, https://www.elsksa.me/scientia/cgi-offline-rendering/cgi-color-management-survival-kit

In regard to PNG, I would strongly suggest this quick read: https://www.elsksa.me/scientia/cgi-offline-rendering/file-format-debunk

I am aware of PNG's strengths and weaknesses. None of which have any impact on the topic being discussed in this thread

[boxfx]

Things may not change since versions but behavior is same and there are not more to do on my side. How can say it better don't know! Also I said what to do in my answer. Read again please.

I gave you a basic challenge in my last post. A task that literally any 3D render engine should be capable of. A task that Octane has been doing correctly for years.

Render an 8 bit srgb image with a straight alpha to any 8 bit file format (tiff, targa, png, psd etc) and have the resulting image look the same as seen in the live view window.

If you can do this, then I would be very appreciative of a c4d project file to show us where we are going wrong with this basic task.

If you cannot do this, then your software has a problem.

[aoktar]

Boxfx, as tried to describe C4D is modifying colors out of my control in case. Also it's not a basic task, it's doing similar things when we have render passes/etc.. Just disable "color management" in Picture Viewer and switch to Linear color profile. I'll give you a sample when I'm back to work. But I think you can do this simple steps before that.

[elsksa]

Hi,
If the output referred rasterized image file does look "washed out", it is likely caused by "a double sRGB EOTF" (mistakenly known as "gamma"). For more information, https://www.elsksa.me/scientia/cgi-offline-rendering/cgi-color-management-survival-kit

In regard to PNG, I would strongly suggest this quick read: https://www.elsksa.me/scientia/cgi-offline-rendering/file-format-debunk

I am aware of PNG's strengths and weaknesses. None of which have any impact on the topic being discussed in this thread

Did you read the upper paragraph?

[boxfx]

Did you read the upper paragraph?

I fail to see what any of those links have to do with the problems being discussed here. One is a needless rant against the png file format. This problem happens in all 8bit formats that support alpha channels.

The other is 35 pages of colour management. We have neither the time, nor the disk space, nor the bandwidth to delve into colour managing our entire pipeline at every stage just so that we can work around a bug which has been recently introduced.

We know this works fine when using linear floating point formats. But this doesn't help us in the slightest, because we're not using those formats.