Even though both have the latest 2.5.2 version.
Jeilin JL2005C gphoto2 support via macports was broken.
brew wound up working.
conversion of the resulting .ppm files then required:
brew install netpbm
download and convert all command:
gphoto2 -P ; for i in *.ppm ; do pnmtojpeg ${i} > ${i/%ppm/jpg} ; done