Photogrammetry vs 3D Scanning: Pros, Cons, and Differences
When it comes to creating 3D models, there are two main technologies available: photogrammetry and 3D scanning. Both techniques can generate highly accurate 3D models, but they have their differences in terms of cost, accuracy, and usability.
So, what are the pros and cons of each method, and which one is better suited for your needs? Let's find out.
Photogrammetry
How it works
Photogrammetry is the process of taking a series of photographs of an object or scene from different angles and using specialized software to reconstruct a 3D model from those photos. The software identifies common points between the images and uses them to create a 3D representation of the object.
Pros
- Cost-effective: Photogrammetry is a more accessible technology since it relies on consumer-grade cameras and specialized software, which is usually cheaper than 3D scanning equipment.
- Non-contact: The object being scanned remains undisturbed throughout the whole process. This is an advantage for fragile or delicate objects.
- Versatility: Photogrammetry can be applied to different types of objects, including organic shapes and large-scale items.
Cons
- Time-consuming: The process can be slow, as it involves taking multiple photos from different angles, which must be aligned and processed to create a 3D model.
- Lighting and environment-sensitive: The quality and accuracy of the model depend on the quality of the photographs taken. A poorly lit or cluttered environment can affect the final result.
- Limited accuracy: Photogrammetry relies on software algorithms to estimate the position of each point in 3D space, which can lead to errors in the final model.
3D Scanning
How it works
3D scanning involves using a laser or structured light to scan an object's surfaces, collecting millions of data points that can be used to create a 3D model. The data collected can be fed into software and assembled into a digital model.
Pros
- High accuracy: The precision of 3D scanners can be in the range of microns, so it can capture details of the object that may not be visible in photographs.
- Speed: 3D scanners can capture a large amount of data in a short time, making it a quicker process than photogrammetry.
- No dependence on the environment and lighting: 3D scans do not require any external source of light, so they can capture the exact measurements of an object without any variation due to lighting.
Cons
- Expensive: 3D scanning equipment can be expensive and require specialized software and hardware to process the data.
- Limited to solid objects: 3D scanners may have difficulty with transparent, shiny or reflective materials. Also, it is difficult to scan the interior of objects or organic shapes.
- Contact-based: 3D scanning may require the physical manipulation of the object to get a complete scan, which can harm delicate or fragile objects.
Differences
Cost
Photogrammetry is generally more affordable than 3D scanning, as it relies on consumer-grade cameras and specialized software, while 3D scanning requires expensive hardware and software.
Accuracy
3D scanning generally produces more accurate results than photogrammetry. Photogrammetry relies on software algorithms to estimate the position of each point in 3D space, while 3D scanning measures the object directly using a laser or structured light.
Usability
Photogrammetry is more versatile as it can be applied to different types of objects, while 3D scanning is limited to solid objects.
Conclusion
Both photogrammetry and 3D scanning are great tools for creating 3D models, each with its own advantages and disadvantages. Choosing the right technology depends on factors such as accuracy, cost, and suitability for the specific object being scanned. But no matter which technology you choose, make sure you have a sense of humor, just like us.