The problem: iMac MacOS OSX El Capitan will not see the AVCHD directory as a directory - cannot pull the file off the SD card.
1. Use "Photos" application to import the videos. Photos is launched automatically, whenever an SD card is inserted into the Mac. I've always dismissed (quit) the app, because I like to be in direct control of my files. In the present situation I let it run and look at the SD card, to see if the videos showed up. They did show in the application window, and I was able to import them, which saved them as LR SBS format .mov files. Then I used VLC to convert them to MP4 (M4V) format. I'll try to post the result shortly, to see how it works out over Youtube or Vimeo.
2. Use Terminal command line interface to access SD card directly. I tried this yesterday without success, not sure what I did wrong. Here's the series of commands that gives me the list of .MTS files (which are the videos):
Macs-iMac-7:/ macuser$ cd volumes
Macs-iMac-7:volumes macuser$ ls
LUMIX3D Newton UHE s o u r c e
LaCie 128Gb Leibniz UHE intermediate
Macs-iMac-7:volumes macuser$ cd LUMIX3D
Macs-iMac-7:LUMIX3D macuser$ ls
MISC System Volume Information
Macs-iMac-7:LUMIX3D macuser$ cd PRIVATE
Macs-iMac-7:PRIVATE macuser$ ls
Macs-iMac-7:PRIVATE macuser$ cd AVCHD
Macs-iMac-7:AVCHD macuser$ ls
Macs-iMac-7:AVCHD macuser$ cd BDMV
Macs-iMac-7:BDMV macuser$ ls
CLIPINF MOVIEOBJ.BDM STREAM
Macs-iMac-7:BDMV macuser$ cd STREAM
Macs-iMac-7:STREAM macuser$ ls
00000.MTS 00008.MTS 00016.MTS 00024.MTS
00001.MTS 00009.MTS 00017.MTS 00025.MTS
00002.MTS 00010.MTS 00018.MTS 00026.MTS
00003.MTS 00011.MTS 00019.MTS 00027.MTS
00004.MTS 00012.MTS 00020.MTS 00028.MTS
00005.MTS 00013.MTS 00021.MTS 00029.MTS
00006.MTS 00014.MTS 00022.MTS
00007.MTS 00015.MTS 00023.MTS
Macs-iMac-7:STREAM macuser$I did not download the MTS files using the command line, because my step 1. above worked nicely, but I offer this in case Photos does not work for you. So this solution # 2. is not fully tested.
3. Use the MacOS Finder (GUI or desktop) to "open" the AVCHD file as a "package." Thanks to T. Stremlau in private communication for this tip. Right-click or control-click the AVCHD package and select "show package contents." From there, drill down through the series of packages to get to the MTS video files. (AVCHD>BDMV>STREAM>files.MTS)
Thanks for everyone's help and tips!
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