Chapter 12 — Capturing with RadianceCap
RadianceCap is the free iPhone companion app for RadianceKit. It stores the known camera pose, lens settings, and available LiDAR depth data for each photo. RadianceKit retrieves this information during import and can use it for camera alignment and to start training.
Recordings are initially stored on the iPhone. You decide whether to transfer a scene via Share, AirDrop, or Files, or to enable optional private iCloud synchronization.
Prerequisites
- To capture new scenes, you’ll need a LiDAR-enabled iPhone running iOS 17 or later.
- Install RadianceCap for free from the App Store.
- On a Mac, you need RadianceKit 1.8.2 or later.
- Devices without LiDAR can still open, review, and share existing scenes, but cannot start a new sensor-rich capture.
Preparing for Your First Capture
When you first launch RadianceCap, it explains in three short pages what data is saved, how to move around the subject, and what transfer options are available. You can reopen the capture guide at any time later by going to Settings → Help → Show Capture Guide.
Before you start, decide whether RadianceCap should capture automatically at regular intervals. The optional motion-triggered capture can trigger an image earlier once you’ve moved far enough. During an active session, these default settings remain locked so that the capture settings don’t change in the middle of a round.
Hold the iPhone so that the subject is completely within the viewfinder. Make sure there is sufficient light, especially indoors. A short exposure time and steady movement are more important than moving as quickly as possible.
Capturing the Scene
- Move slowly from side to side around the subject. Simply rotating in place does not create sufficient parallax.
- Maintain approximately 60–80% overlap between adjacent images. Every important surface should be visible from multiple angles.
- Proceed in contiguous passes. First, complete a full round, and then change the altitude for a second round. Do not switch between high and low positions after every image.
- Avoid people in motion, reflective surfaces, and drastic changes in lighting. Pause the session if you need to significantly change your position without capturing any images.
- A red warning icon means that the image was saved successfully but is clearly suspected of being out of focus. By default, such images are excluded from training. You can review and change this decision later in the scene library.
Finalize and review the scene
End the recording by tapping the stop icon. Only when you finish will the current session become a complete recording bundle that can be transferred and imported into RadianceKit.
Next, open the scene library. There, you can name the scene, add a note, review the individual images, and explicitly exclude images or allow them back into the training set. The original image remains in the capture bundle.
Transfer to Mac
Using Share, AirDrop, or Files
Once you’re done, tap the Share icon or open the scene in the Scene Library and select Share. Transfer the complete .radiancecapture bundle via AirDrop or save it to Files.
Drag the transferred .radiancecapture bundle onto the Import pane in RadianceKit. A capture bundle always represents a complete scene. If another project is already open, RadianceKit will ask for confirmation before replacing it.
With optional private iCloud synchronization
In RadianceCap, go to Settings and enable the “Sync scenes with RadianceKit” option. New completed scenes will then be automatically transferred to your private iCloud storage. Existing scenes will only be synced after you confirm them separately.
On a Mac, open RadianceKit and select File → Open Companion Scenes… or press Shift-Command-C. In other language versions of the app, the menu item may appear as File > Open Companion Scenes….
Small details such as the preview image, name, number of images, and size appear first. The large capture bundle isn’t loaded until you select the scene and click Load or Download.
As soon as the status shows “Ready to Import,” select Import Scene. Large scenes can take up several gigabytes of space. RadianceKit therefore displays Download and Import separately and shows their actual status.
Get started with RadianceKit
During import, the assigned camera poses, the exact optics of each image, and existing LiDAR depth are preserved. RadianceKit therefore does not treat the bundle like a regular photo folder.
After a successful import, RadianceKit offers the Companion Capture preset. Accept this offer for the first run. This will not alter any presets you have saved yourself.
Before training, check the image list and the import instructions. Then start processing as you would with any other scene. Camera alignment, training, editing, and export continue to take place locally on the Mac.
If a scene does not appear
- First, check whether the capture on the iPhone has actually been completed. A session that is still running or has been interrupted will not be offered as a finished scene.
- For iCloud, iCloud Drive must be available on both the iPhone and Mac. Open RadianceCap on the source iPhone until the scene appears as available in iCloud, and then refresh the Companion Scenes window on the Mac.
- The “Available in iCloud” status on the Mac means that the scene is visible, but the large bundle has not yet been downloaded locally. Select the scene and explicitly start the download.
- If iCloud is slow or you don’t have enough storage space, use Share, AirDrop, or Files. Both transfer methods deliver the same complete .radiancecapture bundle.
Privacy and Storage
RadianceCap does not require an account with the developer and does not use any advertising or analytics SDKs. No recording leaves your iPhone without your consent.
iCloud synchronization is optional and uses your private Apple storage. Turning it off stops new transfers but does not delete scenes that have already been synced.
Do not delete local capture bundles until the desired transfer is complete and the import to the Mac has been verified. Large scenes contain depth data in addition to photos and may require a significant amount of storage space.