The more expensive models of iPhones and the iPad Pro in the 2021 version have a Lidar scanner on board. Basically intended to support AR and still camera for lightning fast focusing. But you can also use these devices – with a little patience and fingerspitzengefühl – as 3D scanners!
Lidar stands for Light detection and ranging, or Laser imaging, detection and ranging. The latter is actually more correct because there is always a laser involved. The system is used to capture landscapes, forests and forests in 3D, for example from an airplane or satellite. Lidar is also used for laser guidance of projectiles, navigation of self-driving cars and other vehicles. The Mars helicopter Ingenuity also uses Lidar to visualize the terrain and not accidentally land at an awkward point and fall over. In fact all expensive and professional applications, where a laser beam (or dot grid generated by a laser) is projected onto the target. By then measuring the speed at which the emitted light bounces off a point, the distance can be determined very accurately. You may know this principle from the laser rangefinder. Until now, the more extensive Lidar has mainly been found in professional applications. Until Apple applied the trick to a selection of iPhones and iPads.
Widely applicable
It is only the more expensive models of iPhones and iPads (read: the iPad Pros) that nowadays have a Lidar scanner on board. You can recognize the thing by a dark, somewhat reddish-brown colored hole in the camera module covered by glass. If you have a device with Lidar, most owners will notice this mainly from the fast focusing of the camera – especially at a shorter distance of up to a few meters. This is especially useful in low-light conditions: suddenly all your photos at a party are focused in real-time. Combined with the high light sensitivity and Night Mode (where a whole series of photos are taken in rapid succession and then combined just as quickly) you can take snapshots in dark conditions. Another component in which Lidar (for most users) is used unnoticed is AR or Augmented Reality. The trick in which computer-generated content is superimposed live over an image recorded by the camera. This technique is also used by all kinds of measurement apps and of course also to place virtual furniture in your living room before actually purchasing.
These devices have a Lidar scanner on board:
- iPhone 12 Pro
- iPhone 12 Pro Max
- iPhone 13
- iPhone 13 Pro
- iPhone 13 Pro Max
- iPad Pro 2020
- iPad Pro 2021
Scan
Lidar works excellently for all such applications and in many cases even flawlessly. The Lidar sensor can also be used for another fun thing: making 3D scans of objects or, if necessary, an entire living room. That takes some practice, because the resolution of the Lidar scanner in the iPhones and iPads is actually just a bit on the low side for this application. An image is made up of pixels in three-dimensional space. They are then adjusted in terms of color and exposure based on what the ordinary 2D camera sees. So you have to walk around your intended object, or at least make a partial movement. In this way, covered parts also end up in the 3D grid. Keep in mind that the distance is measured with (laser) light, which goes through transparent objects. This sometimes leads to what can best be described as ‘melting’ glass. But if you take all that into account, after some experimentation you can realize quite nice things!
Scaniverse
What you need in any case is an app that takes care of the scanning work. And for that a very nice copy is available with the name Scaniverse. Extra nice: nowadays completely free, even without further in-app purchases. Start the app and tap Create scan at the bottom of the screen. On the right you will now find a number of buttons. In case you want to capture an object closer, it is important to reduce the range via the RANGE button. Maximum (5 meters) is activated by default. Ideal for when you want to capture a room or other larger object, inconvenient if you want to scan an object on the table. In that case, the background would also be included later in the scan, which leads to significantly larger files and at the same time also creates unnecessary clutter in the image. In short, use that range slider to limit what gets captured to what you want.
You will see a clear red line on the screen that indicates that limit. Then tap the red scan button and move around your object to be captured. When you’re done, tap that button again (which has since turned into a stop button), and you’ll see a coarse, low-resolution preview. You can already rotate that preview with your fingers. Satisfied? Then tap one of the available render resolutions. Certainly the highest resolution can take some computation time, but after a while the 3D image is ready to use. And that use can be purely in-app viewing, or exporting to a 3D file format that is also supported by other 3D editors and the like. With a little bit of knowledge you can then use such an image on a website, for example, or in your own software. Theoretically, you could also send the exported image to the printing software and editor of a 3D printer.
night vision
Another nice thing about Lidar is ‘night vision’. Because an IR laser is used, you can’t see anything in the dark. And where you really can’t see anything with the camera of your device in the pitch dark, Lidar turns out to provide a very nice image of contours with the right app. Not perfect, but useful in an emergency. If only to avoid bumping into objects. Of course, if your phone or tablet works, you also have a built-in LED lamp. But that’s less fun of course. the app Night Vision uses the Lidar sensor to build up an image without a camera. If by chance there is still a very small amount of residual light available, this will benefit the image quality. If not: it works, but sometimes it is a bit abstract. After a while, however, you manage to find your way. Definitely worth a try!
No Lidar but still 3D?
For anyone who does not have a Lidar module in his or her iPhone or iPad Pro, there are also apps available that build a 3D image in a different, more classic way. Namely, by simply photographing a whole series of images of an object, from all kinds of different angles. Then all those photos are combined into one whole. An example of such an app is MeshVideo. The disadvantage is the relatively high price of the Pro version: a tenner. Furthermore, the final 3D rendering is made by a cloud service, which in turn entails possible privacy risks. But it is also possible without Lidar, but it is a lot more hassle.
Future
If Lidar breaks through as a consumer application and a company like Apple sees bread in 3D photos, we can expect a lot from this technology in the future. Certainly for architects, real estate agents, artists, etc., it is very useful to be able to photograph 3D models quickly and in good quality. It can also be nice for you as a humble home user. Capture some special holiday memories in three dimensions. Will that be the future of photography? Well, it probably won’t run that fast, but it is certainly welcome as a nice addition! But then some things still have to be done about the quality (resolution) and ‘accuracy’ of the recording.
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