Smart phones and tablet computers with 2D displays can all display side-by-side image pairs for free viewing.
Many people have been introduced to the freeviewing techniques discussed here through the popular Magic Eye books (www.magiceye.com
) first published in the 1990s. These books, which have sold over 20 million copies, feature computer generated autostereograms that hide a 3D image in a 2D image. To see the 3D image you have to be able to freeview it.
Adobe Acrobat offers a wide range of zoom percentages to choose from.
The 3D Camera app by Juicy Bits creates side-by-side pairs or anaglyphs for viewing on youriPhone or iPad. Courtesy of www.
Once you have captured a pair of images, you may be able to see them in 3D on the camera’s monitor. However you can make them larger, see more detail, and share them with others by displaying them side by side on the computer’s monitor or as printouts. To view these versions in 3D many people use glasses or other viewing devices, but with practice you may be able to view them in 3D unaided—called freeviewing
. When freeviewing stereo pairs you display the two images side by side. To then fuse them into a single 3D image you have to learn to point each eye at only one of the images. There are two ways to do this—parallel and cross freeviewing.
With a little practice most people can learn both techniques although they may find one method easier to use. It is helpful to know how to do both because each has advantages. One reason to learn these techniques is because they let you view your images in their original brightness, color and resolution, something many other viewing methods don’t do as well. You can also see the 3D effects in black and white photos, since color isn’t used to direct the two images to the correct eyes. One of the best things is that you will never be at a loss when you see a stereo pair but don’t have a viewing device. One drawback is that you don’t get any magnification of the images, something lenses in viewing devices often provide.
IT'S GREAT TO BE POPULAR
Throughout this book you Side by side stereo pairs can be printed in books, projected with a 2D digital projector, and displayed on any TV, monitor or mobile device. Viewing stereo pairs is so popular because it require no special processing, hardware or software although viewers can sometimes make it easier.
A layout format called Universal Freeview L-R-L allows viewers the option of parallel or crossed freeviewing. The LR pair are parallel viewed and the RL pair are cross viewed. To lay out photos in this way you can use StereoPhoto Maker or just copy the left image and move it to the far right end so you have three images—left, right, and the duplicate left.
AND IT'S FREE TO BOOT
Throughout this book you will find references to a computer program called StereoPhoto Maker. This free program is widely used by stereographers to view and edit their images.
When freeviewing stereo pairs, here are some things you can do to make the experience more successful and enjoyable:
- Pick a brightly lit setting free of glare and shadows. If using a monitor, display stereo pairs at any size for cross viewing, but for parallel viewing make them 7 inches wide or even less. They will parallel freeview best when the center-to-center distance between the images is roughly the same as the distance
between your eyes—on average, about 2.5 inches (6.5 cm)— or smaller.
When viewing stereo image files on the monitor, StereoPhoto Maker displays the pair side by side and you can adjust their sizes.
Images in the eBook edition of this book can be viewed at almost any size using Acrobat Reader's settings.
- Position yourself and the images so they are parallel to your face, not at an angle. If you are viewing them on a monitor you may have to adjust its tilt.
- Try increasing and decreasing your distance from the images.
- If you wear glasses, try viewing both with and without them. Reading glasses in particular help some people fuse images more easily and when fused let you see details more clearly.
- Relax while viewing and take breaks if you experience any discomfort. Not everyone can successfully freeview stereo pairs, but for those who can, it gets easier with practice and eventually you may be able to fuse them almost instantly. Once images fuse, it's easy to keep them that way as your eyes wander over the scene to examine details, and you'll find it easier to fuse the next pair.
- Don't get discouraged because as you'll soon see there are many other ways to view stereo images.
When viewing full page stereo views in this eBook check that the ruler above is 7" long on your screen for best results. If not, click Acrobat Reader's zoom percentage drop-down arrow to set it as close as possible or type in a percentage figure in the text box next to the drop-down arrow. You also get fine adjustments by holding down Ctrl while you press + and – on the keyboard.