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An iPhone ProRAW stores your location twice: in the DNG and again inside the big JPEG preview packed into it. Clean one and the other still answers the question “where was this taken?”. We handle both, leave the raw data alone, and process on our server because RAW needs ExifTool. Files are deleted within minutes.
Sources of DNG files
- Apple ProRAW (iPhone 12 Pro and newer) and some Android phones.
- Drones and a few cameras that write DNG natively.
- Adobe DNG Converter and Lightroom, which can keep the original file name or even embed the original RAW.
What is inside
| Part | Contains | Personal? |
|---|---|---|
| EXIF / main directory | Make, model, software, three dates | Yes: device, version, time |
| GPS | Position, altitude, speed, heading, date stamp, accuracy | Yes: place and precision |
| DNG identity | CameraSerialNumber, OriginalRawFileName, OriginalRawFileData | Yes: serial, source name, maybe the source file |
| XMP | Develop settings, descriptors of extra images | Edit history |
| Previews, extra images | JPEG preview, mattes, depth | May carry their own metadata |
| Maker notes | Apple's 24 tags in our file | Device details |
| Raw and rendering data | Tiles, colour matrices, black levels, crop | No: needed to develop the image |
Case study: iPhone 12 Pro ProRAW
A 29.2 MB public CC0 sample from raw.pixls.us was cleaned by the live code and examined with a separate ExifTool run.
- Before: 14 GPS tags (including heading, destination bearing and about five metres of accuracy), software 14.3, three dates, three XMP groups and a 5.3 MB preview with the same GPS tags plus the phone model and a host computer name.
- Report: 21 fields removed, none left, file 175 KB smaller.
- Raw data: all 64 tiles identical byte for byte.
- Preview: same pixels, metadata gone. The smaller extra image was untouched.
- Apple maker notes and rendering tags (colour matrices, illuminants, black level, crop, baseline exposure): unchanged.
- ExifTool: one minor warning afterwards instead of two; the original's non-standard-XMP warning left with the XMP.
The preview pass
A RAW's embedded JPEG is a whole picture, and the software that created it may copy the camera's metadata inside, as happened here. ExifTool doesn't look into those pictures while editing the RAW. So we pull out every preview and thumbnail, test each and rewrite any with personal tags. If the format refuses a rewrite, the preview is deleted and the report lists an embedded preview if something remains.
Not all cameras do this: the Canon, Nikon and Sony previews we tested had no personal tags. Phones and converters are where it matters.
XMP and embedded originals
Develop settings from Lightroom or Camera Raw live in XMP and leave with it, so the cleaned DNG opens as an unedited RAW. The ProRAW's XMP held no edits, only a description of an auxiliary sky matte. The matte stays in the file; we haven't tested whether Apple's tools still offer matte-based effects without its descriptor. Keep the original if you use them.
Adobe DNG Converter can embed the camera's original RAW in the DNG, which then carries a full copy with all its metadata. We delete the original file name and the embedded original where ExifTool permits and name them in the report if they stay. We had no such file, so this is untested; re-export without the embed option if you can.
Left untouched
Raw data and extra images, development tags (matrices, illuminants, black and white levels, crop, as-shot neutral), make and model with the unique camera model string DNG requires, and maker notes other than the fields above.
Run it
- Guests clean 5 RAW photos a month, a free account 10.
- Drag the DNG onto the page.
- Wait while fields and previews are cleaned and the result is scanned.
- Read the report; it names the preview if it held metadata and counts what's left.
Limits: 25 MB guest, 25 MB free, 100 MB Starter, 500 MB Pro, 1,000 MB Business. The 29 MB ProRAW exceeds a free account, and phone DNGs often reach 25 to over 100 MB. Originals are deleted as soon as cleaning ends, clean copies within 15 minutes. See pricing.
exiftool -a -G1 -s -gps:all -alldates -software -xmp:all clean.dng
exiftool -b -PreviewImage clean.dng | exiftool -a -G1 -s -gps:all -Other formats: RAW overview, CR2, NEF, ARW.
FAQ
Is the raw data changed?
No. All 64 tiles of a real ProRAW matched byte for byte, and development tags read the same.
Is GPS gone from ProRAW?
Yes: all 14 tags, from the DNG and from the preview's own copy.
Why do previews matter?
They are full JPEGs that can include EXIF with GPS. A cleaner that edits only the DNG tags leaves the position there.
Are Lightroom edits removed?
Those stored in XMP are. Sidecar files and catalogs aren't touched.
Is an embedded original RAW removed?
Attempted wherever ExifTool allows, and reported if it stays. Untested for lack of a sample.
Will my RAW editor still open it?
It validates in ExifTool and the rendering data is unchanged, but we couldn't try every editor. Test a copy in yours and keep originals.
Is the file uploaded?
Yes, over HTTPS, since RAW needs ExifTool. Originals are deleted when cleaning ends and results within 15 minutes. We never open the picture.
Do drone and camera DNGs work?
The method is the same for any DNG, but we tested a phone file only.
Is ProRAW depth data kept?
The extra image is kept; the XMP that describes it is removed, so Apple's tools may stop treating it as a matte. Untested, and a RAW editor doesn't need it.