I´m with both, Jakov and Bob. Thanks for all of this. I have never seeing the 3d effect, how should I do it?
There you go, had described that before somewhere...
1) look at the image, center on the middle gap between them (with your glasses on that you need for reading this text sharp = in focus)
2) place the pointer finger at your nose tip without changing your viewing
3) now still looking straigt to the image, try to focus on your finger
4) move the finger towards the gap between the images
5) follow the finger while keeping focused on it
6) at a certain moment an image "between the images" will appear (looking three dimensional); your finger will be approx. 20cm = 8 inches away from your nose (depending on viewing distance from screen)
7) move your concentration towards that "image between the images" and leave it there (and remove your finger then...)

that's it...