Hi,

Let us break down this workflow with CapCut Space.

The clips edited and re-uploaded by your friend will be limited to 1080p.

Here's why:

1. Editing Device Limitation: When your friend downloads the 4K clips to her phone, the CapCut app on her phone is constrained by the device's capabilities. It will likely process, preview, and edit the video at a maximum of 1080p because that's all her phone hardware/display supports effectively.
2. Saving/Uploading Process: When she finishes editing and uploads the clips back to CapCut Space, the app will likely save or render those edited clips at the resolution it was working with, which is 1080p in her case. It's essentially creating new, edited versions of the clips at the lower resolution.
3. Final Export: Even though the original 4K files might still exist untouched in your CapCut Space, when you incorporate the edited clips uploaded by your friend into your final project and export, CapCut will use those specific 1080p edited versions. Therefore, those segments of your final video will be 1080p. While you can set your final export setting to 4K, the source material for those edited sections is only 1080p, so they will be upscaled, not true 4K, and quality will be lost compared to the original footage.

In summary: The editing process on the 1080p-limited device acts as a bottleneck, downscaling the footage during the edit/save/upload cycle for those specific clips.

Tips and Potential Workarounds:

1. Test it: The absolute best way to know for sure is to do a quick test. Have your friend download one 4K clip, make a simple edit (like a cut), upload it back to Space. You then download that edited clip and check its resolution details. Then try exporting a short project containing only that clip set to 4K and see how it looks.
2. Friend Uses CapCut Desktop: If your friend has access to a computer (even one that doesn't have a 4K screen), using the CapCut Desktop application might handle the original 4K files correctly without downscaling during the editing and sync process back to Space. The desktop app is generally more robust.
3. Your Friend Provides Edit Decisions Only: This is more complex, but one workflow could be for your friend to edit and then describe the edits (e.g., "cut clip X from 0:05 to 0:15, apply filter Y"). You would then perform those edits yourself on the original 4K footage on your end. This only works for simpler edits.
4. You Do the Final 'Conform' and Export: Your friend could do the rough edits on her phone. Then, you take her edited project file (if CapCut Space allows project syncing, not just media syncing), open it on your system, re-link the edits to the original 4K media stored in the Space, and perform the final color grading and export in 4K. This depends heavily on how CapCut Space syncs project data versus just media files.

Tips to Maintain 4K Quality:

1. Edit on a 4K-Supported Device: To preserve the original 4K resolution, it's essential to perform all editing on devices that support 4K. This ensures that the high-quality footage remains intact throughout the editing process.​

2. Utilize CapCut's Cloud Storage: CapCut offers free cloud storage space of 1GB, allowing you to upload and share large video files between devices. By uploading the original 4K files to CapCut's cloud, your friend can access and edit them directly from there, provided her device supports 4K editing.

3. Optimize Export Settings: After editing, ensure that the export settings are configured to 4K resolution. CapCut provides various export options, including 4K, to maintain high video quality.

For a video guide on exporting high-quality videos in CapCut, you might find this tutorial helpful:

For collaborative workflows involving different resolution capabilities, the device with the lowest resolution capability involved in the editing and re-saving process often dictates the resolution of those specific edited assets.