Today’s Question: When I shoot sports, I process the raw images in Lightroom Classic and will often crop the first one in a series of 15 or so images and synchronize the adjustments to the other images. I will sometimes find the crop on subsequent images could be improved upon, so I will highlight other images in that same string of 15 and re-crop and sync again. Because I am cropping some images twice, am I degrading the quality of those subsequent images that have had the second crop?
Tim’s Quick Answer: There will not be any degradation in the quality of the image in Lightroom Classic no matter how many times you refine the crop or any other adjustment.
More Detail: The adjustments available in the Develop module in Lightroom Classic are nondestructive, meaning the pixels in the source image are not altered. You can think of adjustments in Lightroom Classic as simply being metadata in the catalog. The preview you see is a result of the original image with the effect of the adjustments you’ve applied.
No matter how many times you refine an adjustment in the Develop module, whether directly or by synchronizing adjustments across multiple images, there is no degradation of the image caused by the refinements. In effect, no matter how many times you refine the crop settings, for example, the result is as though you had only ever cropped once to the current settings.
It is not until you export a copy of the image or otherwise share it that adjustments apply to pixel values. Even then, the adjustments are only applied to the output you produced, not to the source image on your hard drive.
Because of this aspect of Lightroom Classic, you should feel completely comfortable refining any and all adjustments for any image until you’re completely happy with the result.