Other question : what is the exact effect of "copy" ? Are the files sorted in order of capture ? What is the date used for sorting ? the capture date or date of modification? is it possible to influence this date in file properties ? For example, raw files are sorted by date of capture but the modified files do not refer to the same date.
Otherwise, what is the exact function of "move" ? I imported 3,000 photos with "copy" and the whole tree on the hard disk is changed. How to find the original tree ?
Last question: After corrections, some files on the hard disk does not contain any pictures yet present on the hard drive. I tried to import them without result. Can you tell me if there is a way to fix it?
Thank you in advance for your help
Hi, I will try to help with answers to your questions-
what is the exact effect of "copy" ?
IMPORT BY "COPY"
Lightroom reads your source files and copies them to a new destination of your choosing.
Copy from a camera card places the image files in a destination you choose in the import dialog (your internal or external hard-drive.)
Copy from existing folders in your computer will make new folders containing a 'duplicate' set of images. This duplicate set may have a different folder structure. For example- the 'copy' folders may now have your images in 'Dated' folders (the Lightroom default).
a way to fix it?
Lightroom will only import one version of an image if you have "Dont import suspected duplicates" checked on in the Import dialog. This means you would not see the original folders that you copied from even though they exist on your hard-drive.You could Un-check the "Dont import suspected duplicates" box and import all images (now seeing both sets of folders), then decide which folder structure & set of images you want to keep. Be careful- if you have made Development edits in LR you will lose them all if you delete these images in LR.
Are the files sorted in order of capture ?
Only if you choose "capture time" as the Sort method below the Library Grid view. If you use "Added Order" then images may appear in very random order! especially with derivative modified images.
the capture date or date of modification?
"Capture date" is a Windows file property term and in my system if does not seem to match anything I see in LR.!
In LR it is better to refer to the EXIF data "Date Time Original". (original image files are never modified. But "Date Time Original" can be altered in Lightroom to correct differences in cameras or travel in different time zones. "Date Time Digitized" retains the Camera capture date/time.)
New derivative files like JPG or TIFF that are created from originals retain the "Date Time Original" in Lightroom but I found that the "Date Time" field in LR varies. (Photoshop kept the "Date Time Original", NIK Silver effects changed "Date Time" to the new file creation date.)
Keep exploring Lightroom, it has many things to learn, and I am also a learner.