Photogrammetry creator and viewer

Why use Photogrammetry over LiDAR to capture interiors?

Although LiDAR mode is great for creating relatively quick captures of the interiors of buildings or homes, Photo Mode is a great option if you want photo-realistic recreations of the space that includes finer details. This method will take a bit more time but can result in highly detailed 3D renders of the subject area that LiDAR scan may otherwise not output.

Each 3D gaussian has its own unique parameters such as 3D position, orientation, 3D scale, opacity, and view-dependent color. To render these particles efficiently, they are converted into 2D space (“splatted”), and then organized/sorted for performant rendering.

How do I create an XL Photogrammetry scan?

Creating an XL Photogrammetry capture is similar to how you'd capture an interior space using LiDAR mode, but with some extra steps in order to make sure you're getting extra coverage of the space.

First, prepare the space you want to recreate. You will need clear paths around the perimeter of the space. You'll also want to take note of any potential obstacles that may impede your movements as you make your way around the space. You will be making 3 different passes around the space, with each accomplishing different things.

The first pass will be taken around the perimeter of the space. Place your back against the wall so you're facing in towards the center of the space and choose a starting point so you remember where to end this first pass (a door/entrance works great). Here, you should point your camera up towards the ceiling and capture frames downwards towards the floor. Take a single step to either direction of yourself and repeat this process until you've made a complete revolution of the space.

Ideally, you'll want at least a 30% overlap between frames, but preferably 50% overlap for best results!

The second pass will involve positioning yourself towards the center of the space - imagine a small “ring” that encircles the center point of the room. This will be the path you'll take as you stand towards the center of the space and face outwards. Repeat the process of taking several captures from each position along the center “ring” until you've made another complete revolution.

The third and final pass will aim to add realistic details into your render. Identify any notable objects, landmarks, or fixtures within your interior space that you'd like to focus on. Start off by capturing frames up close by the object, and gradually move away from it so that you can capture frames that contextually place the point of detail within the rest of the interior. Repeat this process for anything that has finer details.

Once you've finished, you should have a large number of frames that need to be processed - this is great! For best results, open up your workspace on your computer and select “Create a capture”. From there, select “Create a 3D Model”. Select all of the photos generated from all 3 passes and wait for Polycam to process your XL Photogrammetry capture.

Keep in mind that you can use any camera available with this technique - including a DSLR camera! Whatever device you end up using, try to use as wide of a lens as possible to help you capture more within each frame. On your DSLR this means a wide-angle 10mm or 20mm lens, and if you're using your iPhone, make sure you're using your wide-angle lens (0.5x).