Using the .xmp workflow, this creates a 'custom' .xmp file per image. How can we then batch process the .cr2 images in ACR without first converting to jpg? Because now the .xmp files are no longer the same so you can't just duplicate the .xmp file, right?
To clarify this step I expanded the Opening Post as follows:
XMP WORKFLOW for PC
1: Make sure your camera time is not ahead of the computer time you will be using.
2: If the name of your CR2 file does not agree with the xmp, change the XMP always. In this manner the xmp will be modified after the CR2. If you do it the other way ACR will not read the files. Always the CR2 Modified Time Stamp mus be before the xml Modified Time Stamp.
3. Once you have the cr2 and the xmp ready for processing you open
all of the cr2 files with ACR. If you have too many files for your pc capabilities then do them in groups.
4. In ACR click on Select All. Top left.
5. Once the cr2 files are loaded, make sure that the sliders are not modified in the Basic tab. Do all the exposure adjustments in the Tone Curve tab.
6. Click on Save Images (Bottom Left) and choose your preferred type. I use tiff for best results.