Photo Mechanic writing ACR data into my raw files?

[Elliot_n]

(Photo Mechanic Version 5.0, build 19749 (20d085a), Mac 0S 10.13, Photoshop 21.2.4)

Hi

I’ve been a happy Photo Mechanic user for many years, sorting/rating Nikon nefs in PM, and then editing them in Photoshop ACR.

I recently ran into a problem. A client requested about 50 raw files from a shoot I did two years ago. (I wouldn't normally hand over raw files, but in this case it made sense.) I didn’t want to give the client the files with all my ACR adjustments, so I copied the nefs into a folder WITHOUT their corresponding xmp files.

But when I checked this folder of nefs in ACR on a different computer they opened with all my adjustments (brushes, gradients etc) still in place.

I’ve since done some tests with some fresh nefs, and this problem only seems to occur if I change the PM star/colour ratings AFTER the the nef has been edited in ACR. Unfortunately this is something I do a lot

Questions:

Why is this happening (I assume I’ve got my PM preferences set up incorrectly)?

I have many years of nefs that will be in this state - will the fact that PM seems to have written ACR data into the the nefs themselves affect their future readability?

Is there any way I can restore my nefs to their virgin state?

Many thanks for any advice

[Kirk Baker]

Elliot,

Why is this happening (I assume I’ve got my PM preferences set up incorrectly)?

Because your IPTC/XMP preferences allow RAW files to be modified and they likely had some small amount of XMP metadata in them when the photo was taken by the camera.  PM will then keep the embedded XMP in sync with the external XMP (the XMP sidecar file).  If you don't want your RAW files to be modified you should uncheck the "Allow RAW files to be modified" check box.

I have many years of nefs that will be in this state - will the fact that PM seems to have written ACR data into the the nefs themselves affect their future readability?

There are some applications that have trouble with embedded XMP, but most do not.

Is there any way I can restore my nefs to their virgin state?

Yes.  Select the photos you want restored to their original state and from the Tools menu choose the "Revert TIFF-based RAW to Original" command.  If you don't care about the existing XMP in your NEFs then be sure to uncheck the "Backup IPTC/XMP to XMP sidecar files" check box.

When completed, the NEFs should be returned to the condition they were fresh from the camera.

-Kirk

[Elliot_n]

Thanks Kirk - it's great that there's a 'Revert TIFF-based RAW to Original' command. That's exactly what I need to send virgin raw files to my client. I've tested it, and it works as expected.

I'm not sure why my preferences got set like that. I have a vague memory that when I was starting with PM over 10 years ago, I was also thinking of using Lightroom, and perhaps those settings came from a tutorial on how to get PM to play nice with LR? (It turned out that I didn't like LR, and I continue to been happy with a PM > ACR > Photoshop workflow.)

Going forward, I'll leave "Allow RAW files to be modified" unchecked.

Thanks for the help.