Today’s Question: If I am working with an image in a collection in Lightroom Classic and apply changes in the Develop module, what happens [with the original image versus the image in the collection]?
Tim’s Quick Answer: By default, an image in a collection is simply a reference to the original, so applying changes to the image in the collection would cause the original in the applicable folder to be updated as well. If you added the image to the collection as a virtual copy, then only that virtual copy would be affected with the changes not applying to the original.
More Detail: There are two common points of confusion among photographers here as it relates to Lightroom Classic. The first is the difference between photos in collections versus folders, and the second is the difference between the original image and a virtual copy.
When you drag an image to a collection, you’re really just making a reference to the original image (by default) within that collection. A collection provides a quick way to get to specific photos, such as images that are being included in a specific project such as a calendar. An image in a collection is really just an image with a bit of metadata being updated to indicate the image is in a collection. This is similar in concept to adding a keyword or assigning a star rating. All of these options provide ways you can track down specific photos later.
So, the key thing to understand about a collection is that when you add a photo to a collection in Lightroom Classic you aren’t making a copy of the original image on your hard drive. You’re simply adding a reference to the photo to the collection, with the original photo still residing in the applicable folder on your hard drive.
A virtual copy provides the opportunity to have two or more interpretations of the same original photo. So, your original image might be optimized in color, and then you create a virtual copy for a black and white interpretation, and then you make another virtual copy for a sepia-tone interpretation. As with collections, when you make a virtual copy, you aren’t duplicating the original photo on your hard drive, but rather creating an additional set of metadata, so that there can be more than one interpretation of the original photo.
If you simply drag a photo to a collection, it is added as a reference to the original, so changes to the image in the collection will affect the image in the folder, and changes to the image in the folder will affect the image in the collection. That’s because both of the images are really just references to the same photo.
If you add a virtual copy to a collection, changes made to the virtual copy will affect the virtual copy that is visible elsewhere (such as in the folder) but will not affect the original version of the image. If you select one or more photos and create a new collection, in the dialog for creating the new collection you’ll have the opportunity to add the selected photos to the collection, as well as to add them as virtual copies if you want the references in the collection to represent different versions of the original photos.