The 7 steps to compositing: a simplified approach to set up, combine & enhance your ZBrush render passes in Photoshop.
This short PDF Cheat Sheet serves as a quick reference guide or tutorial to combine ZBrush BPR passes in Photoshop. The guide features a methodical approach that can be reduced to 7 simple steps to create an appealing image like this one:
The image above, is the result of the compositing workflow described in The Cheat Sheet for Compositing and it is made out of very simply render passes created in ZBrush 2019 and blended in Photoshop CC. The compositing process is non-destructive and it allows you to produce lots of variants to prototype and choose your preferred look and feel:
These are other colour combinations I tested while designing the creature example for the cheat sheet:
A very interesting alternative method to exporting render passes from ZBrush into Photoshop, is to blend different materials directly from ZBrush. Using the new BPR filter options from ZBrush 2019, you can achieve a pretty convincing effect by mixing materials and blending passes.
You can, for instance, work with the SkinShade4 material to create your polypaint and once you do a single BPR, use the Material Shading BPR filter to override the SkinShade4 with any material you need.
What’s really powerful about this method, is that you can take advantage of the BPR filter sliders to control how the new material is applied. Here is an example (especially obvious on the mask for the gold material):
So making use of the BPR filters, particularly the Material Shading filter, you can completely change the look and feel of your render. Here is a ‘side-by-side’ image of the creature where the only difference (aside from the angle) is the BPR filters enabled. The model, the polypaint and even the render is exactly the same:
Sometimes the BPR filters can be overwhelming since they have a lot of options, but working with them is really simple. So here is a mini tutorial on how to set up the filters to combine materials directly in ZBrush.
STEP 1 – Do a quick BPR render. After the render is completed, enable a single BPR filter (form the render palete) and choose the Material Shading filter at the bottom of the filter list.
STEP 2 – Click the Txr thumbnail (texture) in the Material Shading filter, to open up the Material quick pick palette and choose the material you want to blend.
STEP 3 – Set the Material Shading to 100%, click the modifiers button and enable all switches in the Modifiers. The ‘Override Mesh color’ is the one you want to enable to replace the entire model with the selected material (gold in this example).
STEP 4 – Now you have access to all the controls from the BPR filters to blend the chosen material with the ‘render underneath’. In this example, since I render a creature with polypaint, I can use the RGB sliders to restrict the Gold material only to a certain hue of my polypaint (green in this example).
That’s it. Remember you can use up to 12 BPR filters, so you could have 12 different materials blended in a single ZBrush BPR.
In episode 12 from my #ZBrushLive sessions, I walk you through the set up for the BPR filters I used to achieve the alternative look on the sample creature from the Cheat Sheet for compositing:
BPR filter with Material shading around the 35min mark. The technique I used to sculpt the carvings or ‘symbols’ on the body and head of the creature – around the 1h 50min mark.
This last tip/trick was actually suggested by DeVries in ZBrushCentral when I posted the progress of this Cheat tsheet.
I thought this process was really cool so I wanted to share it as a little extra tip to wrap up this short guide. The trick consists on utilising the BPR filters (up to 12) to set up different materials so that you only need to render once and then simply toggle on or off the different filters to save the ‘Composite’ pass (new in ZBrush 2019).
All you have to do is render your model once, and select the Material Shading filter in all the available BPR filters. Then choose up to 12 different materials that you want to render as Extras for your composition (you can refer to STEP 4 in the Cheat Sheet).
In ZBrush 2019, you’ll notice that there is an extra BPR pass that you can export call ‘Composite’. This is the render pass that takes into account any BPR filter settings so click on it to export after switching on/off the different filters.