Author Topic: Gamma issue between Corona VFB and C4D Picture viewer  (Read 7726 times)

2015-12-01, 22:03:14

Seth Richardson

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So I have noticed that Corona VFB is doubling the gamma.  Here is an example.

Is there any reason for this and how do we match the two?


2015-12-02, 09:58:04
Reply #1

4b4

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I don't seem to be getting the same here, can you upload a scene file?

2015-12-02, 11:06:09
Reply #2

Nejc Kilar

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Perhaps you should check if the exposure settings are the same in both?

2015-12-02, 17:09:29
Reply #3

Rhodesy

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Are you using a high gamut monitor? I have had years of frustration with vray and gamma and I have also noticed that if I use the interactive renderer in Corona on a high gammut monitor the colours are different to the editor. I now have an sRGB monitor as my main monitor as its just not worth the hassle.

2015-12-02, 17:16:00
Reply #4

Seth Richardson

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I do have a high gamut monitor yes, however its calibrated to SRGB on profile one.

This is a bug I think because when I mouse over the corona VFB it flashes between the over gamma'd version and the linear version.  The windows originally matched with C4D set to SRGB but I changed it to linear to get the right gamma out of it.  You can tell that Corona is wrong if you look at the red I have on the slider for the material vs the pink you see in the VFB.  Even the material preview below in the screenshot you can see the proper colors and gamma vs Corona VFB.

Classic double gamma.

I will upload though

2016-02-26, 15:57:21
Reply #5

Jarda

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Could you upload the scene, pls? We'd like to look into the issue. Thanks!

2018-02-22, 13:34:45
Reply #6

spawnik

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I have very similar problem with the color differences between Corona and Cinema PV.
Couple days ago this problem don't existed.

2018-02-22, 17:10:35
Reply #7

iacdxb

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I don't think there is any issue with R18, OSX.

...
Cinema 4D S22.
Mac Pro, Mac OS Catalina, 128GB, 2TB.

2018-02-22, 18:32:59
Reply #8

spawnik

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iacdxb, you have same problem but it's hard to see in two separate viewers.
Here you can see the differences.


2018-02-22, 19:14:44
Reply #9

iacdxb

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iacdxb, you have same problem but it's hard to see in two separate viewers.
Here you can see the differences.

Small minor correction setting can be set with VFB post tab....! have you tried to compare with view port render....?

...
Cinema 4D S22.
Mac Pro, Mac OS Catalina, 128GB, 2TB.

2018-02-22, 21:26:37
Reply #10

TomG

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There is a difference, I notice that it doesn't matter whether Corona post-processing is applied or not (eg you can turn off Tone Mapping etc and there is still a difference). Also, there is no difference if you save to EXR from the PV and then from the VFB, both EXRs looked the same for me in Photoshop.

2018-02-22, 22:35:25
Reply #11

ozwald

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Hello friends, I wanted to tell you the following.
Working with Vray and watching many tutorials, the best way to work is to have the work profile in linear mode.
In this way all the textures change, and you must work with very clear textures.
since the final render must be seen with very clear textures.
This result is to be able to play with high counts values in post, achieving spectacular results.
The render should come out as a photo RAW 32 bits with all the colors very clear and it is in post that you create the settings.

However!! I do not know if Corona Render should work in the same way. since I have performed the same steps as Vray in Corona, but the results are not the same.
I wanted to know if you work the same?
There is some tutorial to know about this topic.
How is the right color profile to work with Corona?

Thank you

2018-02-23, 14:35:48
Reply #12

TomG

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Hi Ozwald, yes Linear workflow should be used - see https://help.c4d.corona-renderer.com/support/solutions/articles/12000010221

If you think there is an issue ("since I have performed the same steps as Vray in Corona, but the results are not the same.") can you let us know what steps, and show what the results were?

Thanks!
   Tom

2018-02-23, 15:10:46
Reply #13

ozwald

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Hi Ozwald, yes Linear workflow should be used - see https://help.c4d.corona-renderer.com/support/solutions/articles/12000010221

If you think there is an issue ("since I have performed the same steps as Vray in Corona, but the results are not the same.") can you let us know what steps, and show what the results were?

Thanks!
   Tom


Project configuration> Linear workflow: on
Project settings> Input color profile: sRGB

I was placing in Linear color profile and not sRGB I think that was the problem.
I'm going to prove.
Thank you very much for the contribution

2018-02-26, 19:09:28
Reply #14

Gianni333

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I have the exact same problem. Didn't notice that before. The image saved directly from the corona vfb looks perfect, however saved from the c4d
picture viewer or via a saving path it looks like the gamma is too low. I tried to fix it in post but it seems not to be possible to match the original image with
gamma corrections. Saving the image and passes by hand from the corona vfb seems to solve the problem, but for an animation with many frames
that's not doable. Would really appreciate any ideas even for just temporary workarounds.
3D Artist from Switzerland