Photorealistic rendering is the process of creating digital images that closely resemble real-life photographs. This can be achieved through the use of advanced computer graphics techniques and software, which are able to mimic the behavior of light and materials in a realistic manner.
The use of photorealistic rendering has become increasingly important in a variety of industries, including architecture, film, and video games.
Where in architecture, photorealistic renderings can be used to visualize and present designs to clients in a more realistic and immersive way, and in the film and gaming industries, photorealistic rendering is used to create realistic visual effects and environments, allowing for the creation of increasingly realistic and immersive experiences for audiences.
Overall, the goal of photorealistic rendering is to create images that are indistinguishable from real photographs, providing a level of realism and detail that can be difficult to achieve through traditional art techniques.
In this article we delve into the techniques and technologies used to achieve photorealism, as well as some of the challenges and limitations of this type of rendering.
What is a Photorealistic Rendering?
A photorealistic rendering is a digital image that closely resembles a real-life photograph. It is created using advanced computer graphics techniques and software that mimic the behavior of light and materials in a realistic manner. The goal of photorealistic rendering is to create images that are indistinguishable from real photographs, providing a high level of realism and detail.
Benefits
There are several benefits to using photorealistic rendering for architectural visualization:
- Realism: Photorealistic rendering can create highly realistic images that are indistinguishable from photographs. This can be particularly useful for architectural visualization where a high level of realism is often desired to help communicate a project.
- Visual appeal: Photorealistic rendering can create visually appealing and engaging images that are more likely to grab the attention of viewers. This can be useful for marketing and promotional materials, as well as for creating visually striking designs.
- Improved communication: Photorealistic rendering can help to better communicate design concepts and ideas to clients, stakeholders, and other audiences. By creating highly detailed and realistic images, it is easier to convey the appearance and features of a product or design.
- Efficiency: In some cases, photorealistic rendering can be more efficient than building physical prototypes or models. This can save time and resources, especially in the early stages of design where multiple iterations may be necessary.
- Flexibility: Photorealistic rendering allows for a high level of flexibility in terms of design and visualization. It is possible to make changes and adjustments to an image quickly and easily, without the need to build or modify physical models.
What the differences between photorealistic rendering and non-photorealistic rendering?
Photorealistic rendering is the process of creating images that are visually realistic and lifelike. Non-photorealistic rendering, on the other hand, involves the use of techniques such as line art, outlining, shading, and distortions to create a stylized or artistic representation of an object or scene.
One key difference between photorealistic and non-photorealistic rendering is the level of detail and realism that is achieved. Photorealistic rendering often involves the use of pixel imaging techniques to create highly realistic images, while non-photorealistic rendering may be less concerned with achieving a high level of realism.
Both photorealistic and non-photorealistic rendering techniques can be used to create a wide range of visual content, including photos, models, and other types of images. The choice of which technique to use will depend on the specific goals and needs of the project.
Why is photorealism important?
3D photorealistic rendering, in particular, is a valuable tool because it allows for the creation of images that are indistinguishable from photographs, while being more cost-effective and efficient than traditional photography.
Photography requires a significant amount of time and resources, including props, a team of people, and editing, whereas rendering only requires specialized software and an expert to create realistic and visually appealing images. As a result, many businesses and companies are turning to photorealistic rendering as a more practical and cost-effective alternative to traditional photography.
Types photorealistic rendering
There are several types of photorealistic rendering specifically for architecture, including:
- Exterior rendering: This type of photorealistic rendering is used to create realistic images of the exterior of a building or structure. It can be used to visualize the finished appearance of a building during the design and planning stages, as well as for marketing and promotional materials.
- Interior rendering: This can be used to visualize the finished appearance of a building’s interior during the design and planning stages, as well as for marketing and promotional materials.
- Landscape rendering: This is used to create realistic images of the surrounding landscape and environment of a building or structure. It can be used to visualize the finished appearance of a building’s landscape and surroundings during the design and planning stages, as well as for marketing and promotional materials.
- 3D floor plans: 3D representations of floor plans can be used to visualize the layout and design of a building’s interior during the design and planning stages, as well as for marketing and promotional materials.
- Virtual reality (VR) and augmented reality (AR): These types of photorealistic rendering involve the use of VR and AR technology to create immersive 3D experiences of buildings and structures. They can be used to visualize the finished appearance of a building in a more interactive and realistic way, as well as for marketing and promotional materials.
What are photorealistic renderings used for?
Photorealistic renderings are commonly used in architecture for a variety of purposes, including:
- Design and planning: Renderings are used by architects, designers, and planners to visualize the finished appearance of a building or structure during the design and planning stages. This can help to identify potential issues and make necessary changes before construction begins.
- Marketing and promotion: Photorealistic renderings can be used by real estate developers, builders, and other industry professionals to market and promote properties or projects. They can be used to create visually appealing and realistic images that showcase the features and amenities of a building or structure.
- Visualization and communication: Renderings can be used to visualize and communicate design concepts and ideas to clients, stakeholders, and other audiences. They can help to better convey the appearance and features of a building or structure.
Technologies for Achieving Photorealism
There are several techniques and technologies that are commonly used in the creation of photorealistic renderings. These include:
- Ray tracing: This is a rendering technique that simulates the behavior of light by tracing the path of light rays as they interact with objects and surfaces in a virtual scene. Ray tracing allows for the creation of highly realistic lighting and shadow effects, as well as accurate reflections and refractions.
- Global illumination: This refers to the calculation of indirect light in a scene, taking into account the way that light bounces off of surfaces and objects. Global illumination can help to create more realistic and lifelike lighting in a rendering, as it accounts for the way that light is naturally scattered and absorbed in the real world.
- Texturing and shading: The process of adding texture and color to the surfaces of objects in a rendering is known as texturing, while shading refers to the calculation of the way that light interacts with and is absorbed by these surfaces. These techniques help to add realism and detail to a rendering by giving objects a sense of depth and surface properties.
- High dynamic range imaging: This refers to the use of images that have a wider range of luminance values than standard digital images, allowing for the creation of more realistic lighting and contrast in a rendering.
- Anti-aliasing: This technique is used to smooth out jagged edges and reduce the visibility of pixelation in a rendering, helping to create a more realistic and smooth appearance.
By combining these techniques and technologies, it is possible to create highly realistic and photorealistic renderings. In the next section, we will discuss some of the challenges and limitations that can arise in the process of creating these types of images.
Challenges and limitations of photorealistic rendering
While photorealistic rendering has come a long way in recent years, there are still several challenges and limitations that can impact the realism and quality of these types of images. Some of these include:
Computational power requirements
The process of creating photorealistic renderings can be computationally intensive, requiring powerful hardware and software to handle the calculations and simulations involved. This can limit the complexity and scale of the scenes that can be realistically rendered, as well as the speed at which the rendering process can be completed.
For example, large, detailed scenes with multiple objects and complex lighting conditions may require significant computational resources to render in a realistic manner. Additionally, the use of certain techniques, such as global illumination or ray tracing, can significantly increase the computational demands of the rendering process.
Difficulty in achieving realism in complex lighting conditions
Realistic lighting is one of the key elements of photorealistic rendering, but achieving this can be challenging in complex or dynamic lighting situations. This can be especially true when it comes to simulating indirect light and the way that it bounces off of different surfaces and objects.
For example, creating realistic-looking caustic patterns (the patterns of light created by refraction through a transparent or translucent object) can be particularly difficult.
Limitations of current rendering software and techniques
While rendering technology has come a long way, there are still limitations to what can be achieved with current software and techniques. This can include issues such as the inability to accurately simulate certain materials or lighting conditions, or the need for significant computational resources to achieve high levels of realism.
For example, some materials, such as subsurface scattering (the way that light penetrates and scatters within a translucent object), can be difficult to simulate accurately with current techniques. Additionally, the use of certain techniques, such as global illumination, can be computationally expensive and may not always be practical for use in real-time rendering applications.
While photorealistic rendering has made great strides in recent years, there are still challenges and limitations that can impact the realism and quality of these types of images. In the next section, we will discuss some of the ways in which these challenges and limitations may be addressed in the future.
Future of photorealistic rendering
As rendering technology continues to advance, it is likely that many of the current challenges and limitations of photorealistic rendering will be addressed. Some possible developments in this field include:
Advances in rendering technology
As hardware and software continue to improve, it is likely that the computational requirements and limitations of photorealistic rendering will be reduced. This could allow for the creation of more complex and realistic scenes with fewer resources, as well as faster rendering times.
For example, the use of techniques such as ray tracing and global illumination may become more practical for use in real-time rendering applications due to improvements in hardware and software efficiency.
Additionally, the development of new rendering techniques and algorithms may allow for more accurate and efficient simulation of certain materials and lighting conditions.
Increased use of photorealistic rendering in virtual and augmented reality applications
As virtual and augmented reality technologies continue to advance, it is likely that photorealistic rendering will play a larger role in creating immersive and realistic virtual and augmented reality experiences. The use of photorealistic rendering can help to create more believable and lifelike virtual environments, enhancing the immersion of users in these environments.
Additionally, photorealistic rendering may be used to create realistic virtual objects and characters for use in augmented reality applications.
How do i make a photorealistic rendering? – Tips, tricks, and methods.
There are several techniques that can be used to create a photorealistic rendering, and the steps you take will depend on your specific goals and the tools and resources you have available. Here we list a selection of our favorites:
Lighting
One way to tell that a 3D rendering is fake is by looking at the lighting. To create photorealistic renders, it’s best to mimic the lighting of real-world environments as closely as possible. Of course, 3D rendering gives you some creative freedom – you can create scenes that wouldn’t be physically possible in real life – but basing your lighting setups on reality makes your renders more believable to viewers.
To create a physically accurate lighting setup in 3D, start by identifying all of your light sources. Consider their positions, shapes, color temperatures, and intensities. Then, recreate these sources in your 3D scene, trying to mimic reality as closely as possible.
Interactive rendering and light mixing (in Corona and Vray for example) are both helpful tools for this stage, as they give you instant feedback and allow you to experiment with different values and perfect your lighting.
Sometimes it can be difficult to identify the characteristics of a light, especially if your eyes are adapting to different situations. For example, you might be outside on a sunny day, with the sun shining down and interior lights on inside a building. The intensity of the sun might overpower the interior lights, making them almost imperceptible.
But at night, the same interior lights might appear much stronger and emit a warm, tungsten color, in contrast with the dark blue sky. When you go inside the building, these same lights might lose their orange tint and appear white. The characteristics of the interior lights haven’t changed – only your perception of them has.
Here are some guidelines for light temperatures:
- Cloudy sky: 6500 kelvins
- Midday sun: 5500 kelvins
- Morning or evening sun: 4000 kelvins
- Standard light bulbs: 3000 kelvins
- Candle: 1800 kelvins
Finally, don’t be afraid of shadows. They’re a great way to add contrast and can be used as a compositional element to guide the viewer’s attention to your focal point. Beginner artists often use large area lights or ambient lights, which can destroy shadows and don’t behave like real-world light sources. Avoid these types of lights, and use more realistic sources instead.
Camera angle
In addition to using a physically-based lighting setup, try to use a camera angle that is also physically possible. There are certainly situations where it makes sense to break this rule, but in general, try to keep your camera between 50-170cm above the ground, or high enough that it could be a drone or helicopter shot.
Humans are not used to viewing the world from more than 2 meters off the ground, so a perspective from these heights can feel uncomfortable.
For the focal length, aim to keep it between 16-50mm for interiors and 30-100mm for exteriors. When setting up your camera, don’t just place it in the corner of a room with a wide-angle lens. Experiment with different compositions and crop in to focus on details.
Atmosphere
Adding a subtle layer of atmospheric fog can make most exteriors look more realistic and improve the composition of your scene. It helps to lower the contrast of the background and create a greater sense of depth. But be careful not to overdo it – adding thick fog to a sunny, midday exterior will have the opposite effect.
Lens effects
Photographers generally try to remove lens effects such as bloom and glare as much as possible, but in 3D rendering, these effects can increase realism when used subtly. Be careful not to overdo it, as excessive bloom and glare can make it obvious that an image is a render.
Look at photographic references for guidance on how to use these effects effectively.
Depth of field is another effect that can add realism to 3D renders when used effectively. Keep in mind that in photography, depth of field becomes shallower (creating a stronger effect) the closer a subject is to the camera. We recommend using depth of field on close-up, detailed shots as a way to draw attention to your focal point.
Scale
One of the most obvious giveaways that a render is fake is incorrectly scaled objects. This is especially true for elements that we see in everyday life, such as people, cars, furniture, and architectural elements. To avoid this issue, set your units to a measurement you are comfortable with (for example, millimeters) and double-check that the scale of any models you create or import matches up with the real world.
In addition to being aware of the scale of objects, it’s also important to make sure that the textures on those objects are accurately scaled.
Take the time to ensure that the UVs and material tiling of objects match the scale of the real-world material they represent. While you’re at it, check that the orientation of the texture is correct and that it is not repeated or tiled.
If you do have a texture that is noticeable repeating, try replacing it with a larger texture. If that’s not an option, you can also try copying the texture, offsetting it, and using a noise map to mask it over the original texture. This will create more variation and prevent textures from appearing tiled.
Round edges
Sharp edges don’t exist in real life, and they shouldn’t exist in your 3D models either. Rounded edges add realism to your models by improving the way light and reflections affect an object and giving it smoother, more natural highlights.
There are several ways to achieve this effect. One common technique is to use the chamfer modifier in 3ds Max. Just make sure to set the tension to 0.5 for a rounded (convex) chamfer, add enough segments for a smooth transition, and adjust the minimum angle if necessary.
Alternatively, you can use a turbosmooth modifier and add supporting edges to your model. This creates rounded edges and can sometimes give you a more realistic result, but it’s more time-consuming and creates additional geometry.
A third option is to round the edges using a material rather than geometry. To do this, you can add an edge texture (like CoronaRoundEdges or VrayEdgesTex) to the bump slot of your material. This is a fast method, but it doesn’t create additional geometry, so edges may still appear sharp at intersections.
Imperfection
By adding imperfections that make sense in your scene, you can increase the realism of your renders. For example, you might include variations in a wooden floor that show years of use and cleaning, or a fingerprint texture that simulates the oily residue left on a smartphone.
One common way to add these imperfections is to use the gloss channel of your material. This simulates the way that real-world surfaces reflect light, and in most cases, the effect is subtle. Just be sure not to go overboard with it.
Another way to add imperfections to a material is to simulate edge wear. This is when an object has more wear on its edges than on its flat surfaces, and it’s often caused by scratches on painted, polished, or varnished materials. You can simulate edge wear in 3D by using a layered material and a combination of imperfections and edge textures (like CoronaRoundEdges or VrayEdgesTex) as a mask. This gives you control over the different materials and where they’re applied.
Textures
Textures are an important aspect of 3D rendering, as they help to convey the nature and scope of your work and make it more recognizable to your audience. Textures can be used to add detail and realism to your 3D rendering, as well as to include effects such as reflection and surface imperfections. Textures can be created using various tools and techniques, such as the texture mapping setting in 3D software or by using displacement maps.
Irregularity
One common mistake in 3D rendering is that the final image looks too perfect. To avoid this, try adding some chaos and randomization to your scene. To make your scene more realistic, vary the position, rotation, and scale of your objects.
Finally, don’t forget to add variety to your materials as well. In nature, even objects made of the same material often have subtle variations.
Making your 3D renders look real can be pretty tricky if you’re diving in blind and not knowing where to begin. In this video, Dustin Valkema from PPO EDU talks about a few tips and concepts that can help you on the path of creating photorealistic imagery with CGI.
There are of course many tutorials and courses available on this topic, some of which we mention here.
FAQ’s about photorealistic rendering
Which render type is only photo realistic?
A photorealistic render is a computer-generated image that is meant to look as realistic as a photograph. This can be achieved through the use of advanced rendering techniques and accurate lighting, materials, and scene setup.
There are several types of rendering techniques that can be used to create photorealistic images, including ray tracing, path tracing, and rasterization. Each of these techniques has its own strengths and limitations, and the one that is most suitable for creating a photorealistic image will depend on the specific requirements of the project.
In general, ray tracing and path tracing are considered the most accurate and realistic rendering techniques, as they simulate the way light behaves in the real world by tracing the path of light rays through the scene. Rasterization, on the other hand, is a faster but less accurate rendering technique that works by breaking the scene down into small pixels and approximating the way light interacts with objects.
Is real-time rendering photorealistic?
Real-time rendering is a rendering technique that is used to create images that can be displayed in real-time, as the name suggests. This means that the image is generated and displayed on the screen at a high frame rate, typically 30-60 frames per second, allowing the user to interact with the scene in a seamless and smooth way.
Real-time rendering is used in a variety of applications, including video games, virtual reality, and interactive simulations. It allows for the creation of immersive and interactive experiences that can be explored in real-time.
While real-time rendering can be used to create high-quality and detailed images, it is generally not considered to be photorealistic. This is because photorealistic rendering techniques, such as ray tracing and path tracing, are typically much more computationally intensive and require significantly more time to generate an image.
As a result, they are not suitable for use in real-time rendering applications where the frame rate needs to be maintained at a high level.
Instead, real-time rendering techniques typically rely on faster but less accurate rendering methods, such as rasterization, which are able to generate images at a high frame rate but may not be as realistic as those produced using more advanced rendering techniques.
To sum up…
Overall, photorealistic rendering is a powerful tool for creating realistic and immersive digital images, and its importance is likely to continue to grow in the coming years.
The continued development and advancement of rendering technology and techniques will be key in addressing the challenges and limitations of photorealistic rendering, and in bringing us closer to achieving true photorealism in digital media.
