Here I’m going to explain how to see 3D pictures without 3d glasses.
This is called "free-viewing."
There are three basic ways of looking at 3D pictures with both eyes...
1. Normal Viewing 2. Parallel Viewing 3. Cross Viewing
1. Normal Viewing:
Normally, if you look at or read something on the computer monitor, you aim your eyes directly at the surface of the monitor.
2. Parallel Viewing:
With the parallel method the lines of sight of your eyes move outward toward parallel and meet in the distance at a point well behind and beyond the image. That's why it's called parallel viewing. When you parallel-view, the muscles inside your eye that control the focusing lens relax and lengthen.
3. Cross Viewing:
Another method for 3D viewing is called cross-viewing or the cross-eyed method. You aim your eyes so that the lines of sight of your eyes cross in front of the image. When you cross-view, the muscles inside your eye that control the focusing lens contract strongly and shorten.