For the basics of importing, go to Importing Photographs.
If you're saving both raw and JPEG files on your camera, Lightroom will:
• Import the raw file.
• Add + JPG to the raw file name displayed in Lightroom.
The JPEG file is hidden as a sidecar file.
If you want to edit the JPEG file, press Ctrl + r.
If you want to see both the raw file and the JPEG file in Lightroom, do the following.
1) Go to Edit > Preferences (Windows) or Lightroom > Preferences (Mac).
Or, press Ctrl + ,.
2) Click the General tab.
3) In the Import Options section, in the middle, select Treat JPEG files next to raw files as separate photos.
Your photographs, in iPhoto, are not easily accessed by Lightroom.
The original files, and their edited versions can be imported with some effort.
You'll loose any Events.
Keywords associated with raw files won't transfer, as these keywords are stored in sidecar files, and are not embedded in the raw file.
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You can import a folders or photographs by dragging them onto the work area in the Library module.
Windows users should use the Lightroom icon on the Desktop, not the icon at the bottom of the screen.
Mac users should use the Lightroom icon in the Dock.