zip
uncompressed archive exclude folders
7zz a -mx0 -bb1 '-xr!.dropbox' '-xr!.dropbox.cache' "Snapshot.7z" /Volumes/Data/Dropbox
add to (uncompressed) archive with 7zip
a = add
-mx0 = no compression
-bb1 = do some logging
7zz a -mx0 -bb1 target.7z FOLDER
extract with 7zip
7z x filename.7z
unzip to folder
unzip images.zip -d images