Is there a way to compress a RAW (DNG) photo to an HEIC (or a JPEG) on iPad without losing the metadata? I tried saving the RAW photo as a file, changing the format there and then resaving the image, but that scraped all of the original time, date, and location information. Thank you in advance for any advice.
iPad Pro, iPadOS 26
I have used exiftool to copy metadata from the originals to the re-encoded images and movies. For example:
Copy all metadata from one image to another and set file dates:
exiftool -m -overwrite_original -tagsFromFile source.cr3 -All '-FileCreateDate<ExifIFD:DateTimeOriginal' '-FileModifyDate<ExifIFD:DateTimeOriginal' destination.jpg
Copy all metadata from .cr3 to same name .jpg in the same folder and set file dates in batch mode:
exiftool -m -overwrite_original -tagsFromFile %-.0f.cr3 -All '-FileCreateDate<ExifIFD:DateTimeOriginal' '-FileModifyDate<ExifIFD:DateTimeOriginal' *.jpg
Copy all metadata from one movie to another and set file dates:
exiftool -m -overwrite_original -api QuickTimeUTC=1 -tagsFromFile source.mov -All:All '-Track*Date<QuickTime:CreateDate' '-Media*Date<QuickTime:CreateDate' '-FileCreateDate<QuickTime:CreateDate' '-FileModifyDate<QuickTime:CreateDate' destination.mp4
Copy all metadata from .mov to same name .mp4 in the same folder and set file dates in batch mode:
exiftool -m -overwrite_original -api QuickTimeUTC=1 -tagsFromFile %-.0f.mov -All:All '-Track*Date<QuickTime:CreateDate' '-Media*Date<QuickTime:CreateDate' '-FileCreateDate<QuickTime:CreateDate' '-FileModifyDate<QuickTime:CreateDate' *.mp4
...but does not work on an iPad. Usually Mac's Lightroom quite well preserves metadata in its output (there is a setting for that).
aJmoore55 wrote:
Lightroom with the understanding after some searching that that would maintain all metadata only to find out that it drops the location data when pulling the compressed image back into photos.
In my previous post "Lightroom quite well preserves metadata in its output (there is a setting for that)" does just that if you set it in the export settings:
Unfortunately I have attempted this and I’ve found that none of the metadata is retained when pulling it back over into photos from preview or files. But thank you so much for taking the time to reply I really appreciate it. 🙂
Take care to use the latest exiftool version -- for example support to copy iPhone movie lens metadata was added a few months ago.
Thank you so much for taking the time to reply I really appreciate that. I’m sorry for being dense, but does this process require doing this for every single image separately? I have more than 1000 DNG images, so I’m really looking for a straightforward all inclusive process for compressing the image into a smaller file size while maintaining all of its original meta-data.
Update: I downloaded Lightroom with the understanding after some searching that that would maintain all metadata only to find out that it drops the location data when pulling the compressed image back into photos.
I mean is there something I’m missing here… shouldn’t there be a simpler way to compress your own photo without the need of outside applications and repeated exporting and importing…? 😩
aJmoore55 wrote:
but does this process require doing this for every single image separately? I have more than 1000 DNG images, so I’m really looking for a straightforward all inclusive process for compressing the image into a smaller file size while maintaining all of its original meta-data.
In my previous post exiftool option "Copy all metadata from .cr3 to same name .jpg in the same folder and set file dates in batch mode" does just that.
Thanks for the exiftool examples. That's particularly useful for the videos.
You could just import the DNG to Preview and then Export as jpg. I just tried it, and the Exif metadata seems to be intact. You can do it with multiple files at once.
Thank you Matti, I have not updated exiftool for quite some time.
Is there a way to compress a RAW (DNG) photo to an HEIC (or a JPEG) on iPad without losing the metadata?
