I have a folder with 57 images, but LR imports only 42 of them. Trying to understand why, I find that the ones that don't import are lacking extensions.
These are old files in different formats: psd, jpg, tif, tiff
Is it true that LR needs an extension in the filename, or it can't import the image?
If so, is there a way to add extensions to many images without having to rename them individually?
Lightroom does use the extension to identify the file. It depends on what your operating system is on how to do renames of multiple files at once.