Category: lessons

3D Imaging

3D Imaging

Wiggle 3D Example

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Anaglyph 3D Example

Background:

Depth perception is the ability to view our surroundings in three dimensions – length, width and depth (in Cartesian coordinates, x, y, and z).

Seeing our world through the slightly different viewpoints of our two eyes is called stereopsis. Viewing scenes from two different angles (binocular disparity) allows us to triangulate and converge on different focal points, which lets us calculate distances and spatial relationships between objects.

Photographs are a two dimensional representation of the real world. One can achieve some depth perception through techniques like perspective (converging parallel lines), relative size, occlusion (blocking), and focus blur, but the brain has to be “fooled” into seeing 3D when viewing a 2D image.

The most common method of 3D imaging is stereoscopy, which combines two offset images.

The two types of stereoscopy we will create are anaglyph images and wiggle stereography.

Anaglyph images are created by applying colored filters (typically red and cyan) to offset images, then viewing the images with similarly tinted glasses. Wiggle 3D images are created by animating between two offset images. Both methods can be applied to the same set of original photographs.

Taking the photographs

-Take two photographs from eye-width apart (approx. 2.5 inches).

-Your subject should be in the middleground with foreground and background elements to create parallax for depth perception.

-Your subject must remain in the same position between shots.

Keep the camera horizontal (use a tripod if available).

Photoshopping the Images

For Wiggle 3d:

– Open both images in the same Photoshop Document and name the appropriate layers “right” and “left”

– Lower the opacity on the top layer and align you subject (all other elements of the photo will be misaligned – you want this), then increase the opacity back to 100%.

– Open the “animation” window. Switch to “frame” view. Whatever is visible in your canvas will appear in the first frame. Copy the frame and lower the opacity of your top layer to 0.

– Adjust the timing and experiment with inserting “tween” frames for maximum 3D effect.

– When finished, go to file > save for web and save as a .gif. Large Gifs load slower, so be sure make you image size no larger than 500 pixels wide.

 

For Anaglyph:

Repeat the first two steps for Wiggle 3D.

Select the right eye and go to Image > Adjustments > Levels. This will open the following box.  Drop down the top menu and select the Red channel.

 

Now, at the bottom where it says Output Levels: change the 255 to 0 and click OK.  This should change your layer to a green-blue color (cyan).

Now select the left layer and open the Level… dialog box again. Select the Green Layer. Change the Output Level to 0.  Select the Blue Layer and change the Output Level to 0.  Click OK.  This should turn the top layer to bright red.

Select the top layer (left or right) and in the box where it currently says Normal change it to Screen.

Save your image.