3D applications have become increasingly important in various industries, such as architecture, engineering, construction, and software development. It allows professionals to create accurate and detailed representations of physical objects and spaces, enabling them to make better decisions and create more effective designs. However, several techniques are available for creating 3D models, each with advantages and disadvantages. This article will compare two popular methods: photogrammetry and laser scanning.
What is Photogrammetry?
Photogrammetry is a technique that uses photographs to create 3D models of objects or spaces. It involves taking multiple photographs from different angles and using specialized software to stitch them together and create a 3D model. The software uses algorithms to calculate the distance between points in the photographs and creates a 3D representation based on this information. It even works for
Advantages of Photogrammetry
- Cost-effective: Photogrammetry is more cost-effective than laser scanning, especially for smaller projects. All that is needed is a camera and software, which are readily available and affordable.
- Fast: Photogrammetry is quick; capturing multiple images takes only a few minutes. Depending on the project’s complexity, the software can create a 3D model in minutes or hours.
- High-resolution images: Photographs used in photogrammetry can be of very high resolution, allowing for accurate representation of fine details. This brings easy scalability in quality if needed.
- Versatile: Photogrammetry can be used for various applications, including architecture, engineering, archaeology, and medicine.
Disadvantages of Photogrammetry
- Dependent on lighting conditions: The quality of the photographs used in photogrammetry highly depends on lighting conditions. Poor lighting can result in blurry images, which will affect the accuracy of the 3D model.
- Limited accuracy: Photogrammetry has limited accuracy compared to laser scanning. It is best suited for creating models with a level of detail that is not critical, such as for visualization or design purposes.
- Manual intervention: Although the software used in photogrammetry is advanced, it might require some manual intervention to ensure the accuracy of the final 3D model.
What is Laser Scanning?
Laser scanning is a technique that uses a laser to create a 3D model of an object or space. The laser emits a beam that scans the object, measuring the distance between points and creating a 3D representation based on this information. The resulting model is highly accurate and can be used for various purposes.
Advantages of Laser Scanning
- High accuracy: Laser scanning is highly accurate, making it suitable for applications where precision is critical, such as engineering or surveying.
- Large scale: Laser scanning can create 3D models of large spaces, such as buildings or entire cities.
- Non-destructive: Laser scanning is a non-destructive technique that does not damage the object or space being scanned.
Disadvantages of Laser Scanning
- Costly: Laser scanning is a more expensive solution compared to photogrammetry, especially for small projects.
- Slow: The laser scanning process can be slow, with scanning a single object taking several hours.
- Limited resolution: Laser scanning can produce lower-resolution images than photogrammetry, which can affect the texture quality of the final 3D model.
Which is Better for 3D applications: Photogrammetry or Laser Scanning?
Now that we’ve covered the basics of both techniques let’s compare photogrammetry and laser scanning.
When it comes to accuracy, laser scanning is the clear winner. Because it uses lasers to measure distance, it is much more accurate than photogrammetry, which relies on the photos’ quality.
Photogrammetry is much more affordable than laser scanning, as it only requires a camera and software. Laser scanning, however, requires specialized equipment and is much more expensive.
Suitability for Different Object Sizes
Photogrammetry can create 3D models of objects of any size, from small objects like toys to large structures like buildings. Laser scanning, on the other hand, is not suitable for creating 3D models of objects that are too small, as the laser beam may need to be able to accurately measure the distance to the different points of the object.
Photogrammetry and Human Scanning
While photogrammetry is used for various applications, its use for human scanning has recently gained popularity. Human scanning refers to capturing a person’s likeness in 3D, usually for use in video games, movies, or other digital media. In the past, human scanning was done using a combination of traditional photography and manual modeling. However, photogrammetry has made the process much faster and more accurate.
Benefits of Using Photogrammetry for Human Scanning
There are several benefits to using photogrammetry for human scanning. First and foremost, it’s a non-invasive process. Photogrammetry requires no special equipment or preparation than other scanning forms, such as CT scans or MRIs. All that’s needed is a camera and some software. This makes it an ideal choice for capturing human likenesses, as it doesn’t require the subject to undergo any uncomfortable or invasive procedures.
Another benefit of using photogrammetry for human scanning is its speed. Traditional methods of human scanning can take hours or even days to complete. In contrast, photogrammetry can create a 3D model of a subject in minutes. This is particularly useful for industries such as video games and movies, where time is of the essence.
Accuracy is another advantage of using photogrammetry. The resulting models are incredibly detailed and accurate, capturing every nuance of the subject’s appearance. This is essential for industries where realism is critical, such as virtual reality and movie special effects.
Limitations of Using Photogrammetry for Human Scanning
While there are many benefits to using photogrammetry for human scanning, there are also some limitations. One of the main limitations is the need for good lighting. Photogrammetry relies on good lighting to create accurate 3D models. Therefore, the resulting model can be correct when the lighting is good. This can be particularly problematic for outdoor shoots or other situations where lighting is difficult to control.
Another limitation of using photogrammetry for human scanning is the need for multiple cameras. Capturing 3D Humans requires multiple cameras from different angles that take photos in synchrony. This can be a logistical challenge, mainly when space is limited, or the subject is in motion.
Finally, photogrammetry has limitations in terms of surface. While the resulting models are incredibly detailed, they may need to be more suitable for applications requiring even greater detail. This can be particularly problematic for industries such as medicine, where high-resolution scans are necessary for diagnosis and treatment.
In conclusion, photogrammetry is an effective tool for human scanning, particularly for industries such as video games, VFX, software, R&D and e-commerce. You can check how photogrammetry scans of real people look like right here.