transferring photos

OK - make sure you are connecting to the correct usb port on the frame. It should show up as a drive like a usb stick would on your mac.

Export pictures from photos to the frame "drive". (Select the images, then go to file>export. Select kind jpg. Size and compression as you like but no smaller than large.

The photo frame that I have uses a memory card. I crop the images to the screen size (in pixels) of the frame, reduce the file size a bit during export to Medium (to get more photos on the memory card), put the image file is a folder and add the folder to the memory card. Memory cards are normally formatted MS Dos FAT32 and, as such, only recognize a minimum of files in the root directory. That's the reason for the folder.

It will depend on the frame.

Most likly by exporting images you want from photos onto a usb stick, and using that to transfer them from the frame