“Disable Photos auto-launch for all devices” in OS X El Capitan”.

How to “Disable Photos auto-launch for all devices” in OS  X El Capitan”. Open Image Capture by using the spotlight search. Then plug in you're iPhone or card reader. Photos will open but ignore it, or close it. Remember that you are looking for Image Capture. By expanding the window you should see in the bottom left corner of Image Capture, choose “No application” and there you can disable the auto-launch of the application.