Steve,
Yes, that seems to definitely be the case. I've just checked and it looks like the new name started "._" and then the original file number and a new numbering series. I am using Mac X.6.8 So they must be around somewhere, how should I look for them?
If you know what folder they were in and you can find that folder in the Finder then you can use the Terminal (command line prompt) to rename them. Open up a Terminal window by opening up the Terminal application from the Utilities folder within the Applications folder. When the window opens, type:
cd (followed by a space and don't hit enter)
Then switch back to the Finder, select and drag the folder containing the images onto the Terminal window. The Terminal should respond by typing in the full path to your folder for you. Switch back to the Terminal window. Hit enter. Your current directory should now be the folder containing the hidden images.
Now to see them you can type:
ls -al
and hit enter. This will show a long directory listing, showing all files, including those that begin with a period.
Identify your missing files in the list. If there are only a few of them you can manually rename them. The Terminal supports copy and paste so select one of the filenames and copy it (Command-C). Then enter:
mv (paste with Command-V) new_name
where new_name is the name you now want that hidden file to be renamed into. You can paste again and use the cursor keys to move back to the leading period and backspace over it, thus removing it, or you can enter an entirely new name.
If there are dozens or hundreds of names, then please let me know and I'll give you instructions on how to fix them in bulk.
I will be changing the Copy/Rename/Ingest/Live Ingest/inline rename on the Contact Sheet to keep users from making this mistake in the next build of Photo Mechanic 5.
-Kirk