composition of the final image with layers

[Jean-Paul Paloux_cg]

Hi,
I saved all the layers output of a final image independently.
Normally how those are put together ?
Gi+Zdepth+shadows+diffuse ? with all at multiply transparency ? mask for shadows ? thank you !

[joe_b]

composition of the final image with layers

http://www.spot3d.com will take you to the most recent V-Ray support files( though some of it is Max specific a lot of it is just basic V-Ray information. I found some stuff on the different render elements at http://www.spot3d.com/vray/help/150R...erelements.htm - if you look at the very last example image it shows what makes up the RGB channel in the VFB.

Self-illumination + Direct lighting + Global illumination + Reflection + Refraction (all added); the result is the same as the Real RGB Color channel

[Jean-Paul Paloux_cg]

composition of the final image with layers

thx ! very informative !

[Micha_cg]

composition of the final image with layers

... but without reflective layer this method is useless for me.

[joe_b]

composition of the final image with layers

... but without reflective layer this method is useless for me.

Sorry - I only removed layers that were not hooked up on the back-end of V-Ray. I'll request that we get that for our service release. Are there any others you would put on the top of your list of requests for VFB channels?

[Micha_cg]

composition of the final image with layers

I don't know. I would like, if I could get per channel rendering and photoshop the same image like the default output. The same method like for the last example image here (Self-illumination + Direct lighting + Global illumination + Reflection + Refraction)

[Gijs]

composition of the final image with layers

Jean-Paul,

to learn more about it look at this excellent thread:

http://www.chaosgroup.com/forum/phpB...ic.php?t=13818

If you want to use this method though, your need to be working with linear data in an HDR editing environment. Once you use it on gamma corrected output or clipped output it is not going to work. This means you will need high end editing software to work with it. In my opinion, until Photoshop will support this, it is not worth the extra hassle for stills.

[joe_b]

composition of the final image with layers

The following is from the post that Gjis that linked to....The V-Ray forum is currently not available to VfR customers (we're working out the technical details on providing this).

Begin Original Post by cpnichols on V-Ray forum
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OK... it seems a lot of you know that you can rebuild the renders that are split out of the vray g-buffer, but may not be clear on how to do it. Vlado did a very good breakdown on what the elements are here...

http://www.spot3d.com/vray/help/150R...erelements.htm

But this may help you.

The following is a very basic breakdown of how to reassemble a vray image in a compositing program. I am showing it to you in a very straightforward node breakdown, but this can be done in AE or any other package. First thing... you need to be in Linear Color Space the whole time since many of these elements such as Raw GI will be linear.

Lets start by showing the different g-buffers that are needed:

The core is this: the Diffuse. All it is a solid color of what comes out of diffuse, no shading. If you have a texture, it is a texture, a color is a color.

The light is then broken down into direct and indirect lighting. Use the RAW versions.


To get the effected diffuse of these, you multiply them by the diffuse

SO if you take the RawGI and multiply it by the diffuse, and you take the RawLight and do the same, you get the Diffuse direct light and the Global Illumination light.

They look like this:


So now you have the two basic elements of light: the direct light and the GI light (in terms of diffuse light). You can even think of it as key and fill. Light is additive, so all you need to do combine them is the add them together in the comp.

But there are still some pieces missing. And that is your specular light. While Vray really considers specular as a reflection, the cool thing is that it will separate out the reflection of a light as specular and reflection as reflection. Think of it in the same way as the direct light and the GI light. Those two passes look like this:


These two passes can be added to as well. By the way, if you have refraction or self-illumination or things that get split out, you will have to add them too.

So this is how it looks in a diagram:

I am showing some color correct nodes in there since that is what you want to do with this.

You combine all of this: (Diffuse * GI) + (Diffuse * Light) + Specular + Reflection, and you get the same image that you rendered, which is this:

OK great, so you got the same thing you started with, what good is that? Well if you separate things, you have a lot of power to adjust it in post. First thing, I saved everything as full floating point unclamped color. So I already have the power of adjusting the exposure and the gamma of the image. Here are some examples of that:


Ok, but let?s say you want to desaturate the GI and maybe increase the contrast on it a bit. You could do that in Vray GI dialogue and redo the render or you could do a color correction on the Raw GI pass, and you get this:

Want to decrease the intensity of the sunlight? No problem, just adjust the RawLight pass:

Want to increase the reflection and maybe darken everything else a bit? No problem. Simply, darken the diffuse pass, and lighten the reflection pass:

Anyway, I hope this helps you guys.

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End original post by cpnichols on V-Ray forum

[joe_b]

composition of the final image with layers

Just as a note - not all of those channels are available in VfR at this time

[Micha_cg]

composition of the final image with layers

Joe, thank you for the infos. Great.

[Jean-Paul Paloux_cg]

composition of the final image with layers

excellent. thank you !