Supported formats
The files LightPhotos opens on each platform — including the one macOS gets on its own — the three kinds of file it writes next to them, and the catalog that lists your folders.
LightPhotos opens the files straight from disk, in place. There is no conversion on the way in and no copy inside a library — what is in the folder is what you see.
What it opens
- RAW — Sony ARW, Canon CR2 / CR3, Nikon NEF, Fujifilm RAF, Panasonic RW2, Olympus / OM System ORF, Pentax PEF, Samsung SRW and DNG (Leica, Pentax, iPhone ProRAW, Pixel), rendered non-destructively like everything else.
- Ordinary images — JPEG, PNG and TIFF on every platform. HEIC / HEIF, GIF and BMP open in the macOS build only.
HEIC is the platform-specific one. It is the format iPhones shoot, and on macOS it decodes through Apple's own ImageIO framework. The Windows, Linux and browser builds have no decoder for it — no pure-Rust HEIC decoder exists to build them on — so there, HEIC files appear in the grid but do not open. Shooting or converting to JPEG keeps a folder readable on every platform.
Tested cameras
RAW support depends on the camera model, not just the brand. The macOS build decodes RAW through Apple's ImageIO, so it opens whatever Apple's camera list covers. The Windows, Linux and browser builds use the open-source rawler decoder instead. These are the files tested on both:
| Camera | macOS | Windows, Linux, browser |
|---|---|---|
| Sony A7 IV | Yes | Yes |
| Canon EOS R5 | Yes | Yes |
| Nikon D850, Z 6II, Z f, Z 8 (lossless) | Yes | Yes |
| Nikon High Efficiency NEF (Z 8, Z 9) | No | No |
| Fujifilm GFX100S, X-A5 | Yes | Yes |
| Fujifilm X-Trans: X-T4, X-T5, X-H2S, X100VI | Yes | Browse only, from the camera's embedded preview |
| Panasonic S5II, GH6 | Yes | Yes |
| OM System OM-5 II | Yes | No |
| Pentax K-r (PEF and DNG) | Yes | Yes |
| Leica Q2 DNG | Yes | Yes |
| iPhone 12 Pro ProRAW, Pixel 8 Pro DNG | Yes | Yes |
| Samsung Galaxy S23 Ultra DNG | Yes | No |
Nikon's High Efficiency compression is the gap on every platform; shoot lossless compressed NEF for now. Untested cameras from these brands will usually work, but a camera released after your copy of macOS or after the current rawler release may not.
Anything else in the folder is simply left out of the grid rather than raising an error. If your camera does not open, the issue tracker is where requests land.
What it writes
Three kinds of file next to your photos, and one catalog that lists your folders:
| Purpose | Where it goes |
|---|---|
| Ratings and edits | Sidecar files in .lightphotos/, inside the folder you opened |
| Thumbnail cache | .lightphotos/ too, so a folder carries its own thumbnails wherever it moves |
| Exports | An Exports/ folder inside the folder you opened, created on first export |
| Catalog | Your list of folders and preset folders, and a copy of the photos' ratings, flags and labels. Desktop: ~/Pictures/LightPhotos/<name>.lightphotos. Web: the browser's storage |
Your photos themselves are never moved, renamed or modified — the originals are read-only to LightPhotos. That is why exporting produces new files instead of overwriting the old ones, and why moving a folder somewhere else keeps every edit with it.