Today’s Question: Is there any downside to going back to photos I edited a long time ago [in Lightroom Classic or Camera Raw], and updating them to the current [process] version for the purpose of, for example, reducing noise and possibly making a few “tweaks”?
Tim’s Quick Answer: The only real risk of changing the process version for a photo that had previously edited is that doing so can alter the appearance of the photo, in some cases rather significantly.
More Detail: The process version in Lightroom or Camera Raw can be thought of as representing the version of the set of adjustments that are available. That not only includes new features that get added over time, but also changes in the algorithms that determine the specific behavior of individual adjustments.
For example, in the first process version the basic tone adjustments included Exposure, Recovery, Fill Light, Blacks, Brightness, and Contrast. In the current process version (version 6) those have been updated to Exposure, Contrast, Highlights, Shadows, Whites, and Blacks.
If you had made a series of modifications to the tonal adjustment settings for an image using process version 1, and then updated that image to the latest process version, there could be a rather strong change in the appearance of the image. You could certainly then refine the adjustment settings based on the updated process version, but this adds a degree of work and in some cases it may be difficult to get the image back to the look you wanted.
To help manage this issue, when you want to update an image to a new process version I recommend first creating a virtual copy. Then, on the assumption you’re more likely going to want to retain the final image with the newer process version, I recommend leaving the virtual copy as a reference image that reflects the original adjustments, and then updating the adjustments for the original image including the update to the latest process version.
By creating a virtual copy for this purpose, you’ll be able to easily compare the previous and current versions of the image, and also revert to the earlier version of the image should that become necessary.
