i have no problem uploading from SD oe Cf card onto my mac. the other day i wanted to show photos on my TV so i loaded photos from my Mac onto a sd card and the photos showed that they were on the card, but when i inserted the SD card into my 5d mark iv it showed no images. if i take pictures on the camera it shows images and i can show them on my TV. its only show no images when in try to place photos on the SD card from the computer
The finder program on the mac will sometimes put a file on the SD card with a name that begins with a period. This filename might confuse the camera. From a terminal window on the mac,
ls -al /Volumes/EOS_DIGITAL
If there is a file named ".fseventsd", then
Ctrl-Click on EOS_DIGITAL icon on the desktop and select "eject".
And then so long as one does not allow finder to access the Volume, the camera will be able to read the files on the card. As has been suggested, if the photos have been copied somewhere for safe keeping, it is best to let the camera format the card after it has been in another device and not write protected.
I avoid this by moving the switch on the SD card to write protect before inserting it in the card reader on my iMac. I also let the camera format the card when I have backed up all of the photos to multiple storage devices.
I hope this helps.
I think that is pretty normal. The camera will only recognize image files on the SD card that it created. Canon used to have process in place where to camera bodies could share and exchange images. But, you have never really been able to store images on a memory card and then view them in the camera. Somehow, the camera can tell the difference. “Not my image file.”