Problem importing from 64 GB Lexar USB card in LR4 on Mac Mini with external hard drive.

Question

Initiated import after deselecting some images. Import was super quick and I was suspicious as the stick had over 40GB of images. Progress bar indicated completed import. Later when I went to process images the Library module indicated that the files were "missing". Eventually I noted that the images were still listed as on the USB stick and had not been imported - though it seems they were imported into the catalogue and listed there with the thumbnails. Luckily I had not erased the USB stick. How do I avoid a repetition of this scenario? What should I do to complete the import? Should I delete the original and delete from Catalogue and start over again? This happened once before and I lost some good images when the progress bar erroneously (?) indicated completed import. Obviously I did something wrong.

Answer 1

As Rikk Flohr has already suggested, you must have selected <Add> (in the top center of the Import Dialog - although in Lr 4.3 this option is not any more available when importing from card).
<Add> is for importing images that are already on the hard drive and you do not want to change their location.
<Move> is for importing images that are already on the hard drive and you do want to change their location.
<Copy> is for importing images from camera / memory card.
You saw the progress bar when you imported. But that does not necessarily mean that your images have been copied to the hard drive.
Importing from memory card / stick / camera involves a two-step process:
a) the images are copied to the hard drive;
b) the images are referenced in the catalog.
In your case it seems that only (b) happened. Thus you get the message  that the images (i.e. the image files) are missing once you removed the memory stick.
To correct this: Move the images via your OS (Mac Finder / Win Explorer) to a location where you want your images to be.
Then in Lr re-link the catalog reference with the images files. You  do this by right-clicking the folder in question in the folders panel (it should have a question mark in front of the folder name) and selecting <Update folder location> or <Find missing folder>. Navigate to the location of the folder and select it.
For more on re-linking missing images / folders see here:
http://www.computer-darkroom.com/lr2_find_folder/find-folder.htm
http://tv.adobe.com/watch/creative-suite-podcast-photographers/lightroom-dude-where-are-my -photos/
Important:Do not re-import the photos. Re-importing photos that are already in the Lr catalog creates problems.