It does not have to cost several thousand dollars to scan an object into a 3D model. Now you can use your mobile camera to do that, or any other camera.
Photogrammetry is a method where you take pictures of an object that is scanned from all sides and then convert it into a 3D object with dedicated software. This can be an easy and affordable way to 3D scan an object.
If you want to go into the world of 3D scanning but are not ready to pay large sums of money for a 3D scanner, this do it yourself guide may be the right choice for you. Below is a list of the most popular DIY 3D scanners from 2019. But before that, let’s take a little more in-depth look at software for photogrammetry and 3D scanning.
Photogrammetry, the process of estimating 3D coordinates from multiple images of the same object, is by far your cheapest gateway to 3D scanning. While some professional long-term antenna scanners can easily cost hundreds of thousands of euros, you may be able to use cameras hanging in balloons (or kites) to achieve professional-quality results for 1% of that cost.
Using a smartphone camera also does the job. Today’s smartphone cameras are good enough to achieve a very fine print of an entire project. Simply set the camera to manual exposure, hold the camera (or smartphone) in your hand and snap photos around your selected target, from as many angles as you can.
Make sure that there is a good level of overlap in the field of view between the different images (70-80%). Also, try to keep a constant distance from your object and keep it in the center of the frame. You can start by taking 50 photos, but the more photos you take, the more accurate your final model is likely to be.
Photogrammetry relies heavily on the quality of the software used to correlate all images and extract the appropriate set of coordinates that define your object. Compared to laser-based systems, the role of the software in editing, cleaning, healing, inspecting and reproducing your scans is even more important.
Software for 3D Scanning
You have many options in the software market to reproduce and edit information derived from a 3D scan. Usually, this type of software can be quite expensive, and professional hardware manufacturers often provide their own software solution to take the job.
Still, if you have an eye on photogrammetry, you can use a combination of different freely available software, including ColMap or VisualSFM in combination with CMVS-PMVS. These can be further processed with open source software such as MeshLab, Blender or Cloud Compare for correct rendering and editing of the captured information.
If you are looking for an all-in-one package directly from your smartphone or tablet, you can think of TRNIO (iOS), which uses a cloud-based computer system, or SCANN3D (Android), which works locally. (You may want one advanced device for the other.)
For computer-based processing, consider Agisoft Photoscan or Reality Capture. 3DF Zephyr offers a free version that allows you to process up to 50 images. Autodesk also offers the reality software ReCap for both computers and mobile systems. It can be used for photogrammetry of laser-based scans.
$ 30 Scanner
This is one of the simplest 3D scanner projects you can build. The basic idea is to mount a platform on which you dock a smartphone. All you need is a plate that rotates freely around its vertical axis.
To work, you need to connect the phone’s headset. The volume knob must be installed in place under the crank. It fires the camera remotely and takes 55 photos for each full rotation of the object being scanned.
The numbers say a lot about this 3D scanner turntable. The design, made by Daveyclk, has been downloaded more than 170,000 times from Thingiverse. You are free to download all the files needed for 3D printing of this turntable.
Since no motors or electronics are used in this design, you do not need any kind of drivers (or connection to your computer). But to get a lot of images converted to a 3D object, you need photogrammetry software. The designer suggests using 3DF Zephyr for this task.
3D Scan with its camera
Sometimes you can catch yourself wanting a digital 3D representation of a physical object. Maybe you make a replacement part for a broken tool or design a modern vase inspired by the organic shape of a family’s legacy. You can buy a 3D scanner for the job, but why invest in new equipment when all you need is a standard 2D camera, like the one you probably have in your pocket?
Creating a 3D scanner camera from someone who takes 2D images is actually possible – the key is angles and many of them. The process is simple: Download an app to your smartphone, snap many images of the same object from multiple angles and feed them to some special software to produce a 3D design.
Of course, there are minor details to consider in practice to optimize the scan, but the methodology is quite simple.
Just to note that there are electronic devices on the market that work with a smartphone or tablet to produce a 3D scan, but we will mainly talk about using a smartphone itself to create a 3D scanner camera in this the article.
Prepare for photography
The 3D scanning process starts before any pictures are taken, to optimize the physical environment where the scan will own goes a long way towards producing a cleaner model. Just as it is in digital photography, it is easier to get the physical photography conditions (or in this case, scanning) as perfect as possible, rather than fixing a lot of problems during post-processing.
What you want in a 3D scanning site are:
- Soft lighting
- Pure background
- Carpet non-reflective surfaces
Start photographing the object
At this point, you need to decide if you are going to touch your smartphone or desktop software with your 3D scanner camera. Choosing the smartphone path means you will have a more guided and uncomplicated experience, while choosing desktop software gives you more flexibility to manipulate photos. The option you choose depends on how exactly you need the initial scan and how much you are willing to invest in the process.
No matter what software you choose to use, the process of taking photos and using the 3D scanner camera itself is the same. The process involves taking overlapping images of the object from many different angles. A common way to do this is by walking around the object as the ‘scan’ progresses, thus moving the camera and capturing different angles on the object to sew to a 3D model.
It is worth noting that you should never move the item during the scanning process. Just move yourself or the camera around it.
Do not be afraid to repeat the pictures, especially those that require awkward angles. It is much easier to point at a camera than to rebuild a missing part of a 3D model.
Compile the 3D model in software
After you have taken all the photographs / images, these should be compiled into a 3D model in the computer.
There are various programs to do this automatically, and some are listed further up. Regardless of the program, the end product is the same, a 3D model of what the pictures show.
After the model is created in the program, it often takes a little refinement to get it perfect according to your own wishes.
In this guide, we have gone through how to 3D scan with the Photogrammetry method, by taking pictures with a camera to compile the images into a 3D model.
It can be used with basically any digital camera. Mobile cameras nowadays are good, and these are well suited for the task.
The process of taking the pictures can also be facilitated with, for example, the 3D printed tripod from Thingiverse for about 30 $.
It is a fun “do-it-yourself” task to 3D scan something with a camera, and the result will be good if you are good at it. The more you practice, the better you get at it.
You could say that the trick is to take the pictures correctly.
Hope you enjoyed this guide.