|
Here's the two frames we're starting with. You'll remember
them from the last series of steps.
 |
 |
| Left |
Right |
This is the most critical part of the process,
since the 3D illusion depends on precise alignment between
the two images.
- Make either of the images the foreground window.
From the Edit menu, choose Select All (or you
can use a keyboard shortcut: Command-A on a Macintosh,
Control-A in Windows) to copy the entire image
into the clipboard. We tend to perform this first
step on the cyan image, so that the red image will
be the background layer.
- Select Copy from the Edit menu (or Command/Control-C).
- Select the other image window (for us, this is
the red image.)
- Choose Paste from the Edit menu (or Command/Control-V).
The image will be pasted into a new layer, centered
in the existing window and placed above the layer
that was selected, usually the Background layer.
- Repeat the same copy/paste procedure (and layer
rename) with the other image. Then double-click
on the Background layer, click OK on the resulting
dialog box, then drag the layer into the trash.
(This removes the "specialness" from
the layer so that it can be deleted.)
- When you are finished, your Layers palette should
look something like the image on the right:
 |
 |
| The Layers palette context menu. |
The Layers palette. |
- For the moment, your image just looks like the red
image (if you've set the red layer on top, as in this
example.) We'll change that now, using Photoshop's
ability to change the way layers are blended.
- Using the Layer Options menu shown above, select
the top layer and change its blending mode to
Screen. (The Photoshop Help guide explains that
Screen mode "looks
at each channel's color information and multiplies
the inverse of the blend and base colors. The result
color is always a lighter color. Screening with
black leaves the color unchanged. Screening with
white produces white. The effect is similar to
projecting multiple photographic slides on top
of each other.")
 |
| Change Layer mode to Screen... |
- Amazing difference, isn't it? Note that, as promised,
the color effect has returned, with some edge effects
that come from the 3D process. This is because the
final image once again has all three color channels
present.
- Look through a pair of 3-D glasses and manually tweak
the location of one of the images (use the arrow keys
while the Move tool is selected) until the 3D effect
is optimized.
- Crop all white space around the edges of the two
images (draw a box around the two images, excluding
whitespace, then choose Crop from the image menu.)
And now we'll have our completed image, which can
be viewed in both red/green and red/blue glasses (red
lens on the left). Do you see any depth in this picture?
(Note that objects which are pure grey due to lack
of offset from image to image - in this case, the
arm and the object being held - appear to be exactly
in the plane of the viewing screen.)
Previous: Adjusting
Levels | Next: Saving |
