Hi kappa123,
We recommend that you try the steps in the link below since you're havind an issue when connecting your camera to your Mac.
If nothing happens when you connect a camera to your Mac - Apple Support
To perform the recommended troubleshooting steps via the link above, complete the steps in the section below.
*Make sure the USB or USB-C cable is properly connected to your camera and the computer. If your computer has another USB port, try plugging the cable into it.
*Check your camera to make sure it’s turned on and set to the correct mode for importing photos. See the instructions provided with your camera.
*Check your camera’s memory card for damage. See the documentation that came with your camera for more information on this or other possible problems.
We recommend the steps above because they will show you what to do if nothing happens when you connect your digital camera to your Mac.
If you’re still experiencing the same issue, try the steps here: If your Mac runs slowly - Apple Support
Please let us know the outcome after giving the above steps a try.
Thanks for using the Apple Support Communities.
Cheers!