Hi everyone! My name is Emre Karabacak, and I work as a lead 3D artist in Berlin, Germany. In this article, I will show you my lighting process in Marmoset Toolbag 4 using my personal project Chiappa Rhino Revolver 50DS as an example. You can also check out my previous article on Lighting and Rendering Guns in Toolbag to learn more about how I create my lighting.
Before we dive into the tutorial, I want to note that I’ve used Substance 3D Painter as my texturing software and used the Unreal Engine 4 project preset for the texturing and export.
To get started, ensure your mesh is free from shading issues or errors in your 3D modeling package and that your textures are ready to be imported and set up in Toolbag.
You can check your mesh for shading issues or errors in your 3D modeling package and ensure your textures are ready to be imported and set up in Toolbag. Some of the most common shading issues can involve:
- Normal Map – Flipped Green Channel: Your normal map may be flipped if it appears wrong in Marmoset Toolbag but correct in another DCC application. To fix this issue, we must ensure that your DCC export settings match the settings in Toolbag. For example, if you’ve used DirectX for your Substance Painter export, then the Normal Map Tangent Orientation should be Left-Handed (Flip Y checked). If you used OpenGL for your Substance Painter export, then the Normal Map Tangent Orientation should be Right-Handed (Flip Y unchecked). The Normal Map Tangent Orientation setting is under Edit > Preferences > Content.
- Inverted Polygons: Your polygons may have been inverted if you cannot see them because the polygon normals are turned inside out. Select and invert the polygon in your 3D modeling software to correct this.
- NGons: NGons are polygons with five or more vertices. They make mesh triangulation more difficult than quads since they are less predictable for the software. The third image below demonstrates the issues that can happen when using NGons. The topology around the holes is broken, resulting in triangulation through our detail. To avoid this, review your mesh for NGons before you export. This can also prevent mesh or normal map issues. Specifically, Blender has a triangulate modifier for a nondestructive workflow.
Additionally, you can check where your pivot points are set, separate your mesh into multiple objects, and use parenting to modify them later in the Toolbag scene.
In this example, I’m ensuring I can open and rotate the cylinder so it’s logically linked, similar to real life.
Now it’s time to import our model along with its textures. To import the model, use the shortcut Ctrl+I or drag and drop the 3D file into Toolbag. To set up materials, go to the Materials tab and hit the + icon to create a new material. Alternatively, you can drag and drop materials with proper naming conventions (i.e _.albedo, _normal, _roughness) onto a material sphere, and the texture map slots will auto-fill accordingly. After applying the material to your asset, you can set up some cameras.
To set up camera shots, I recommend gathering images and setting up a mood board of similar assets to help spark inspiration. This is also a good stage for iteration and experimentation.
Now onto the Camera settings. I always use a low Field of View value range of around 20 – 25 to create a semi-orthographic shot that captures most of the asset. In the Post Effect setting, I tend to select Hejl as the Tone Mapping method with an Exposure value of around 2.4 – 2.6.
To view your final composition, you can set your desired resolution in the Render object and enable the Safe Frame option in Camera > Lens. Finally, enable Use Ray Tracing, Advanced Light Sampling, and set your Bounces to 2-3 bounces in the Render object.
Note: Before starting to light your model, I suggest reading my other tutorial, “Lighting and Rendering Guns in Toolbag.” In this article, I’ve explained how I create my lighting using the HDRI/Skylight editor.
When it comes to lighting, I always start with the rim light, which is useful for making your model stand out from the background with a defined silhouette. I used a Directional Light with a small diameter and a high intensity to create a sharp contour around some areas. I used another Directional Light in some other areas with a larger diameter to create gradients over the edges
Then I place my key light, which will be the dominant light source in the scene. I used a Directional Light with a Rectangle for the Area/Shape and a brightness intensity of around 4-5. I angled my light source better to display the reflections on the side of the weapon. I pick an angle for the key light placement that shows off the rough and glossy details. In this case, the key light was slightly angled instead of shining directly from my camera perspective onto my weapon. This helped show the surface imperfections.
After placing the key light, it’s time to brighten up the rest of the dark areas. For this, I used a few fill lights, which were less intense than the key light but had a larger diameter. I used a less intense Directional light with a small diameter for fill lights to brighten up the scene.
I’ve also placed an overhead and bottom light to highlight feature areas like the Picatinny rail and cylinder with different light intensities. I used another Directional light for both lights and changed the Area/Shape to a Rectangle with an exaggerated amount for width and height and a low intensity for Brightness. This creates a large, filled-out light that should cover the model to complement the other lights in the scene.
Our goal with this is to give our shapes better readability. I recommend switching your light shape to control the X and Y- axes of your light source size. This gives us another possibility of light source geometry which can be manipulated in two dimensions instead of the diameter.
As a suggestion, watch for effective plane changes when lighting your asset. This makes it easier to read and emphasizes its features for the viewer. To give you an idea, look at the example below. The area where a plane change occurs in the first render appears rather flat, making the shape seem two-dimensional and difficult to interpret. A successful plane change should clearly visualize your object’s shape, distinctly showing the differences between various levels or planes.
Using Sky Lights
After lighting my scene, I always set my Sky object to a low Brightness setting of around 0.2 – 0.5 to create more information in our reflections, like colors, gradients, and shapes, while also making it more lively. This can also help brighten up areas that could not receive light from Directional and Spot Lights. I exaggerated the HDRI value in this example to make the changes more visible.
Setting Up Your Final Render
Now it’s time to create our final renders. To do so, we’ll work with the Render object. We have a few options to tweak in the Lighting section, such as Direct/Indirect Radiance Clamp sliders and Diffuse/Reflection Intensity of the indirect lighting. I recommend experimenting with these options to see what feels good for your render. However, the standard settings are typically good enough.
The next important settings are the Samples and Denoise in the Output tab. We can choose how many render samples per pixel we want with Samples. The higher the samples, the longer it takes to render, which will improve render quality. In my case, I went with 2048 Samples.
The Denoise setting offers both CPU denoising and real-time GPU denoising. When using GPU Denoise, you can expect a smoother ray tracing experience and the ability to navigate your scene without visual artifacts and performance disruptions. CPU Denoising usually provides great render quality using a few samples and works well with fine detail and alpha-blended materials.
In my case, I went with CPU Denoise, set the Quality to High and the Denoise Strength to 0.3. Be careful with the value for Denoise Strength, as you can crunch the details in your texture. Overall, if you go with a high sample count, you should choose a lower denoise strength value; with a lower sample, you should go for a higher denoise strength value.
When satisfied with the results, choose your Output Path, where your rendering should be saved. Ensure your Resolution is high enough, and remember to enable Transparency if needed.
Render Passes & Cameras
You also have the opportunity to create Render Passes like Alpha Mask, Depth, Normals, etc., and render out Material Values such as albedo, roughness, and more. This is handy if you want to composite renders in Adobe Photoshop and fine-tune your rendering. If you use multiple cameras, you could add them to the Render Cameras tab to render everything in one go. I recommend creating a 4K render because having a high-resolution render on hand is always nice. If you have Artstation Pro, you can upload 4K pictures to your portfolio.
Time to polish up our renders. I’m mainly using the Filter > Camera Raw Filter in Photoshop for this. I usually adjust settings like Texture, Clarity, and Dehaze, and I use the masking feature to mask out areas and edit exposure, contrast, etc.
Another cool trick is to lay a simple black-to-white linear gradient layer with its Blending set to Overlay and low opacity to create a focal area in your render. For this asset, I used a gradient along the barrel to make the front of the weapon brighter than the rest.
Since I created this asset, Toolbag has been upgraded with a complete set of post-processing sliders in Post Effects, including Highlights, Midtones, Shadows, and Clarity. This will make creating my final touches easier and quicker by allowing me to stay in the same app.
Creating an Environment for Storytelling
I recommend creating a scene for your asset to make it look more complex and complete. You can also use the environment to tell a story about the model you want to showcase.
There are some libraries where you can get downloadable models or textures, such as Toolbag’s integrated Library, Megascans, Poliigon, and Substance Source. But make sure that your model gets the main spotlight of your render. In addition, I would recommend choosing an environment that contrasts your asset. For example, this weapon is mostly metal, which looks great against a stone (or maybe on a cloth) environment. This highlights the materials of our asset and makes it stand out more.
The most important aspect of lighting is that you showcase your model so that every part (shape, material properties, etc.) is understandable to the viewer and leaves them without questions.
I hope this tutorial helped you to understand my lighting process. If you have any questions, feel free to contact me at email@example.com
We’d like to thank Emre Karabacak for writing this breakdown. You can check out more of Emre’s work on Artstation and discover Toolbag’s baking, texturing, and rendering features using the 30-day trial.