Grouping images helps to improve the structure and clarity of your image collection when displayed in lighttable view.
You can combine images into a group by selecting them and clicking the “group” button in the selected image(s) module, or by pressing Ctrl+G. Likewise, you can remove selected images from a group by clicking the “ungroup” button, or pressing Ctrl+Shift+G. Images generated by duplicating an existing image are automatically grouped. Similarly, if you import multiple images with the same base name, but different extensions (eg.
IMG_1234.JPG), these images will automatically form a group.
The “group” button ( ) in the top panel of the lighttable view toggles grouping mode on and off. If grouping is off, each image is displayed as an individual thumbnail. If grouping is on, images of a group are collapsed, and are represented by a single thumbnail image. This displayed thumbnail is called the group head. If you press the ( ) symbol in the group’s thumbnail, only this group is expanded. If you then expand another group, the first group collapses. To collapse an expanded group again, just click again on the ( ) symbol of its group head.
An expanded group in the filemanager mode of lighttable view is indicated by an orange frame which appears as soon as your mouse pointer hovers over one of the images. This frame surrounds all images in the group.
You can define which image constitutes the group head, while in an expanded view of a group, by clicking on the ( ) symbol of the desired image. That symbol is shown only if grouping mode is enabled, so to change the group head, you need to first enable group mode, then expand the group you want to change and finally click the ( ) symbol on the desired image. To determine which image is the group leader, hover over the ( ) and a popup will identify the group leader.
If you collapse an image group and then enter darkroom mode (e.g. by double-clicking on the thumbnail), the group head image will be opened for developing.
Image groups are also a convenient way to protect an existing history stack against unintentional changes. Suppose you have just finalized an image and want to protect its current version: Simply select the image, click “duplicate” in the selected images panel, and make sure that grouping is switched on and that the group is collapsed. Now, whenever you open the image group again in darkroom, only the group head will be altered. The underlying duplicate remains unchanged.
Note: “duplicating images” only generates a copy of an image’s history stack, stored in another small XMP file. There is still only one raw file.