Compositing Vray Render Elements

In the following tutorial we will go through the process of rendering an image in separate passes using render elements and compose them afterwards in photoshop.

Although I am a vray user, the same method can be used for any other renderer that supports render elements.

1)      Rendering the scene.

In the “render scene” menu, select the “render elements” tab and add the following passes: vraydiffusefilter, vrayGlobalIllumination, vrayRAWlighting, vrayRAWshadow, vrayReflection, vrayselfillumination, vraySpecular.

Note: if you have refracting objects in your scene, you need to add vrayRefraction as well. Also, if you don’t have self illuminating objects you can disregard the vray self illumination pass.

Render the scene and save all the passes (including the main image) in a new folder using descriptive names for each pass.

We still have to render the ambient occlusion pass. There are several ways to do this but I prefer to do it the old fashion way.

Before going forward with this make sure you save a copy of the file.

Select all the objects in the scene and assign them a vray light material. In the map slot choose vray dirt and set the subdivisions to about 30.

 

Before hitting render, disable the global illumination and de-activate disable all the lights (from the Vray global switches menu).

Save the rendered AO pass and open photoshop.

2)      Blending the layers in photoshop.

Open the main image, double click on it and change name of the layer to “original image”.

Open all the other passes and paste them in new layers in the original image file.

Make a copy of the vray diffuse filter layer and re-arrange the layer order as seen in the screen capture bellow:

Hide all the layers except the 2 diffuse layers, the raw lighting and the raw global illumination.

Create 2 layer groups and place one diffuse layer and the raw lighting in one group and the other 2 visible layers in the other group.

In each group, make sure that the diffuse layer is at the bottom.

Change the blending mode of both vray raw lighting and vray raw global illumination to “Multiply”.

 

Set the blending mode of the group above to linear dodge (see image bellow).

Up to this point, your image should look like the one bellow:

Unhide the vray raw shadow layer, and invert it (Go to “image”, “adjust” and click “invert”).

Set the opacity to about 20 and choose “multiply” as blending mode.

Unhide all the layers above, except for the AO pass and the original image and set the blending mode to “linear dodge”.

At this point you can unhide the original image and compare it to the result achieved with the blended layers bellow. You will notice that the blended layers look a bit better than the original image because the vray raw shadow pass gives more contrast to the image.

You can now delete the original image layer (we have only kept it for reference so far), and unhide the AO pass. Adjust the opacity to about 15 and set the blending mode to multiply.

This last step is very useful because it adds more detail and depth to the image.

Needless to say that rendering the image in separate passes is highly recommended because this way you can easily control the lighting, the shadows, etc. without having to render again.

You can download the layered psd file that I have used for this example here.

Additionally you can use vray wire color, vray material id or object id, to adjust the colors, brightness or saturation of each object in the scene independently.

 

10 Comments
  1. This was a good share, and really simplifies the process. I have been using the new PSD Manager plug-in, which helps this process alone nicely.

  2. Wow…..excellent share…i was doing things similar to this, but your way is far the best way.Thanks for sharing !

  3. Thank you for the feedback guys!

  4. Only missed the brightness of the TV in the objects, the rest was cool!

  5. Rajesh says:

    Nice work and simple way of composition ……… thanks for sharing

    Rajesh

  6. Qasam says:

    psdfile.zip where is the file?

  7. Qasam says:

    This method can we use in exterior view please suggest thanks in advance

  8. This method can be used for whatever you like. It really does not matter if it is an interior an exterior an object, etc.
    The main purpose of using this workflow is to have more control in post processing work.

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