Whenever a new gadget is released, we tech writers have to figure out how to take screenshots of the device. It is important that we are able to show readers what the display looks like when we are describing features. You may wish to do this too: you may want to capture a screen to share with a friend or you may need to take a screenshot for someone providing tech support.
With the Apple TV, it’s not that simple. You can’t take a screenshot on the device itself; at least no one has found that magic sequence of button-presses on the remote that captures the display and sends a photo to your iCloud Photo Library. But you may still, even if you’re not a tech writer, need to capture images from the Apple TV, if you are, say, a teacher or trainer. You could just take photos of your TV screen, but that never looks very good.
Read more here:: How to take screenshots of the Apple TV