Stow-on-the-Wold in Genuine 3D.
Sit normally in front of the screen. It may be better to remove spectacles. Hold up your thumb in front of the screen, halfway down the border between the two pictures, and halfway between the screen and your face. Focus on the tip of your thumb, not the screen, and you will now see two out of focus vertical borders a short distance apart. Keeping your thumb between these two borders, gradually bring your thumb nearer to your face and you will be aware of a constricted-width third picture emerging between the existing two pictures. Keep focussing on the tip of your moving thumb and when the central picture becomes slightly wider than each of the side-pictures halt your thumb. While remaining focussed on the tip of your thumb carefully look just above the thumb, at the tree. You will see that the tree appears in 3D. Carefully move your thumb out of the way and carefully look around the new picture and you will see that it is all in 3D. Concentrate on trying not to alter the focus of your eyes and be aware that accidentally tilting the head to left or right can upset the effect. All this takes a little practice but you will soon become expert at viewing the 3D image. Let me know how you get on.
Now view this photo using a slightly different method.