Linear workflow 3d max + vray + photoshop / render elements

[P0studio]

Hello everybody,

I suspect I'm making a mistake at some part of my workflow regarding the liner workflow. Why do I think so? Well, I have 2 situations, which I post together because I have the feeling they are somehow connected:

1. If I just add on photoshop the Gamma adjustment layer with 2.2 gamma, to the beauty pass, it gives me a washout result that doesn't resemble the srgb Vray frame buffer image. Nevertheless both vray and photoshop show me the same gamma 1.0 image. I assume I am not applying the proper gamma correction in photoshop, I don’t really know how to set it up to a linear workflow. I read that I should do it with the Levels adjustment layer but it result in a very contrasted and saturated image.

On the other hand I tested how the same principle in After Effects, based on some post claiming that photoshop is not the right tool for post-processing, and again I couldn't reach the desire results.
The only thing that I did notice is that when I save the image as 32b full float Hdri, or even Tiff the image does not require any gamma correction at all. This does not fit my workflow because I can’t have many layers in one 32b document in photoshop.

2. The second problem I have is that, is that I can’t manage to add the render elements correctly. I have tried many formulas and they are all the same, it just depends on what you add, multiply or divide. The result I get is that some areas are brighter than others, and the colors differ a little bit. Or I get exactly the same color but with black edges artifacts.


Here are my settings for you to check my linear workflow. I hope I'm not missing something out
3d Max + vray

Materials:

• Refraction: affect all channels
• Some maps and textures have been multiplied inside the material editor in 3d max, because I wanted the same material darker or lighter (I don't know if that affects)

3d Max settings:

• Enabled Gamma/LUT Correction
• Gamma 2.2
• Affect Color Selectors and Affect Material Editor
• Input Gamma 2.2 and Output gamma 1.0. The HDRI map was uploaded from the hdri map, not the old bitmap, and the gamma it’s 1.0 by default. HDRI texture is loaded into the dome light with 64 subdivisions

Vray Render settings:

• Global illumination is Irradiance map and light tracer (detail enhancement and pre-filtered are checked on them)
• The AA is DMC
• Color mapping: Linear multiply, Gamma 2.2, Affect background and Don’t affect colors (adaptation only)

Photoshop
srgb screen, set to the default European settings.

Or After Effects
Set to linear workflow


Following are the combinations to add the render elements, which I guess many of you already know and are actually posted in many forum threads here, this are the basics just to fit the beauty pass, imagining that I don’t have any caustics or selfiluminated materials. I didn't write if it's 8bits, 16 or 32, or whether it's HDRI, Jpeg or TIFF, because I tried every combination and still didn't have the correct results.

(All of them were tested in After effect and photoshop so when I write group it could also be a pre-composition)

Option 1	Option 2	Option 3	Option 4
Grouped ( Group RawLighting= VrayLighting/DiffuseFilter + Group Raw GI= VrayGI/DiffuseFilter * diffuseFilter ) + Reflection + Refraction + specular	Group ( (RawLighting= VrayLighting/DiffuseFilter) * Diffuse filter ) + Group (Raw GI= VrayGI/DiffuseFilter)* Diffuse Filter ) + Reflection + Refraction	Lighting + Global Illumination + Reflection + Refraction + Specular (I also checked adding the diffuse filter )	Group Lighting= Raw Lighting * Diffuse Filter + Group GI= Raw GI * Diffuse Filter + Group Reflection= Raw Reflection * Reflection Filter + Group Refraction = Raw Refraction * Refraction Filter + Specular (I also checked adding the diffuse filter )

Thank you for taking your time to read such a long thread. I really hope someone can help me figure out what I am doing wrong, because I have absolutely no clue anymore. If there is already a post covering this, I'm sorry then for re-posting, I honestly couldn't find a combination among post that could follow the entire workflow (3d max + vray + photoshop)


P0studio (Paola)

[tashko.zashev]

Hi,

It will be difficult to say what makes the difference between the beauty and comp results without the scene.
I see that you have set reflections/refractions materials to affect all render channels. Therefore you have to mask those objects in the reflection/refraction element, because their info persist in the other elements too.

[P0studio]

Hi,

It will be difficult to say what makes the difference between the beauty and comp results without the scene.
I see that you have set reflections/refractions materials to affect all render channels. Therefore you have to mask those objects in the reflection/refraction element, because their info persist in the other elements too.

Hi,
Thank you for answering Tashko, how should I make the scene available for you?. I noticed I can upload images, videos or links, but can we actually upload a scene?

Please let me know, and thanks again

P0studio

[tashko.zashev]

Hi,
Thank you for answering Tashko, how should I make the scene available for you?. I noticed I can upload images, videos or links, but can we actually upload a scene?

Please let me know, and thanks again

P0studio

You can post archived scene here or send to support@chaosgroup.com in case that your work is confidential.
To attach it here, you need to use the Advanced mode (Go Advanced) when posting new reply. Unfortunately the max file size is around 10mb.

[P0studio]

You can post archived scene here or send to support@chaosgroup.com in case that your work is confidential.
To attach it here, you need to use the Advanced mode (Go Advanced) when posting new reply. Unfortunately the max file size is around 10mb.

Well we got a problem there because the 3d max file is 100mb already. I wasn't the only one modelling it so it has too many polygons. I can only send a lot of snapshot of the render settings, the materials settings and the lights settings. Do you think that would help or is not enough?

[tashko.zashev]

Well we got a problem there because the 3d max file is 100mb already. I wasn't the only one modelling it so it has too many polygons. I can only send a lot of snapshot of the render settings, the materials settings and the lights settings. Do you think that would help or is not enough?

It will be better to see the entire scene, because the difference may come form the gamma setup, shader, lighting or even map.
You could send a request to our support@chaosgroup.com for details about our FTP server, in order to upload the files there.

[P0studio]

It will be better to see the entire scene, because the difference may come form the gamma setup, shader, lighting or even map.
You could send a request to our support@chaosgroup.com for details about our FTP server, in order to upload the files there.

Hello,

I was not allowed to upload any scene, according to my office is a confidential project. So I started to run tests again to figure out what causes the troubles and it seems to be with the hdri in the dome light.
As long as I don't attached any map to the dome light, I have no troubles at all, but I did this very fast at the office on a test scene and unfortunately I don't have vray at home, so I will have to get back on this topic next week.
Thanks for the help, I appreciate it a lot

P0studio

[P0studio]

don't affect colors - format - linear workflow

Hello,

For those of you who ended up in this thread looking for answers I could tell the problem was with the render settings, to be specific on the color mapping settings, the don't affect colors(adaptation only) box.

I checked several other threads and tutorials and here are some in case some of you want to read more on the subject:
http://forums.chaosgroup.com/showthr...+affect+colors
http://forums.chaosgroup.com/showthr...+affect+colors
http://forums.chaosgroup.com/showthr...+affect+colors
http://www.davidfleet.com/tutorials/linear-workflow

I noticed I didn't correct the gamma to 1.0 when this option was not enabled, therefore my images were to bright.

Once I checked that my render settings were working properly, I merged my old scene into the test scene and did a test with an override material. I compared the following images and they all looked exactly:

1. Image with added gamma 2.2 in photoshop
2. Image saved from the VFB already in gamma 2.2.
3. Image resulted from composing the render elements and adding the gamma 2.2 in photoshop.

So far, both the basic test scene and the one with the override materials were working well.
The problem came when I enabled the original textures. The result in photoshop was a bit washed out. I test this with gamma set to 2.2 in the color mapping and don't affect color (adaptation only) on
And I also test it with the gamma set to 1.0 and the on't affect color (adaptation only) off. The both gave the same wash out result. It is not completely wash out, just a bit.

The textures are all loaded in gamma 2.2, since I set that on th 3dmax gamma settings, it's also quite obvious when a texture is not set properly.
The HDRi is loaded through the vrayHdri map, and it is set to 1.0 though some tutorial recommend 0.85 to create more contrast

Anyone has an answer to this?

Thanks a lot

P0 studio

[svetlozar.draganov]

Hello,

Thank you very much for the detailed explanation of the issue but like Tashko said earlier it would be very difficult to track where the issue comes from without any examples scenes and output render elements. The setup you are using is the right one and it should give you the same appearance between Vray and PhotoShop/Affecter Effects.
What file format are you exporting from Vray and in what bit depth ?
Since the project you are working on is confidential wouldn't it be possible to prepare a simple scene with the same setup which also contains the issue and send it to us for investigation ?

[P0studio]

This shows the settings from the simple test image

Materilas and HDRI map. Dome light:



3d max settings, render settings, render elements and file format



Results in photoshop:



As you can see here, the results in terms of light once corrected into 2.2 gamma, are equal to the original VFB 2.2 image, except for the reflection on the blue box, that I pointed out in the comparison at the bottom of the image.
The composition of the render elements as well as the RGB element, gave me the same results.
This is why I am wondering what kind of curve is applied at the VFB to make it 2.2 and what curve is photoshop applying. I think that's were the difference is.

I will add next,the results of the scene with the override material and afterwards the scene with the materials. I just don't want to put it all in the same post

[P0studio]

This are the results from the override scene as you can see every image shows me exactly the same result.
I just took some of the original objects from my original scene and merged them into the simple test scene I had. There you can still see the 3 boxes, green blue and transparent. The HDRi and render settings are the same as I didn't change anything



The composed element image doesn't have the background element, there fore behind the window it looks darker, but everything else looks the same

[svetlozar.draganov]

Can you attach that scene along with HDR file ?

[P0studio]

Here are the merged materials that came with the obejcts from the old scene. Aa I wrote before, the render settings, and HDRI are the same



What you can observe in this image is that the gamma correction applied in photoshop is not the same as the gamma curve that the VFB applies, but It can't be that the gamma is applied twice because the brightness of the image is almost the same.
What I think is that the gamma that we assume the texture have (2.2) is not 2.2. Or by adding the color correction map, or multiplier map, I change something. I have no idea



The other weird thing is the IEs lights, but I don't know if that affects. I just have 2 IES lights, and if you see the power of them, is just too high according to normal physical calculations.



this are the camera settings


As you can see is a very simple scene. I'm sorry I couldn't upload the original one

P0studio

[svetlozar.draganov]

We don't need the original one - a test scene is just fine.