Showcasing images and photos is one thing, but really capturing people’s attention in a media-soaked world is another. That’s why 3D has recently become so popular again. There are two main types: stereoscopic, where two cameras are used to capture an image, generally to create 3D movies; and anaglyph 3D.
Anaglyphs are an older technology and rely on colour channels, but they can be used in media such as print. Best of all, you don’t need to have created a 3D image to start with. Using Photoshop, you can manipulate the colour channels to create various types of anaglyph 3D from an existing 2D image. For this tutorial, you’ll need a pair of green and magenta glasses to view the images. The other type have red and cyan lenses.
1. Simple manipulations
The essence of creating anaglyph 3D pictures from a single image is to manipulate the colour channels. Start by loading an image, and in the Layers palette click on Channels and then the Green channel. The image should turn grey when only this channel is selected.
2. Instant depth effect
Click on the Move tool in the Tools palette, and click and hold anywhere on the image. Drag about 3mm to the left and let go. Now click back on the RGB channel in the Layers palette to recombine the image. Put on the 3D glasses and you should see that the image is behind the monitor front.
3. More depth options
This next effect requires an image where the content is angled across, so that objects on one side are near the camera and those on the other side are further away. This is how to enhance the effect with 3D. Go to the Green channel again and then press Cmd-A to select all.
4. Sliding depth
Go to Edit > Transform > Scale and grab hold of the control point halfway down the left side. Click, hold and drag to the left to scale the Green channel to the left. Now when you recombine the channels, the right side of the image will appear at the front of the monitor while the left will recede into the distance.
5. Front to back
Select the Green channel and press Cmd-A. Go to Edit > Transform > Distort. Grab the top-left control point and move it left. Repeat with the one on the top right. Combine the channels and when you look at this one, the bottom of the image appears on the screen, then recedes as you look up the to the top.
6. Two-layered system
Let’s look at some other things that can be achieved by splitting the image into two depth levels. Load a portrait photo and toggle Quick Mask to On. Click on the Paintbrush and set the opacity to 100%, the foreground colour to black and the brush hardness to 75%. Paint over the background, leaving the figure.
7. Cut out the figure
Zoom in to go around the edge of the figure and use a small brush to paint around any strands of loose hair. Once complete, toggle the Quick Mask off so it becomes a selection. Then, press Cmd-C to copy the figure. Select the Layers palette and create a blank layer. Press Cmd-V to paste the figure in.
8. Fake some background
Moving the green channel will cause a large streak to appear. Turn off the visibility for Layer 1 and select the Background layer. Zoom in to 100% and click on the Clone Stamp tool. Set the opacity to 100% with a blend mode of Normal. Clone scenery from the left of the face, over the left side of the face.
9. Move the channels
Click on the Channels tab in the Layers palette and select the Green channel. Click on the Move tool and move the channel to the left as demonstrated earlier. Click back onto RGB, then turn the visibility for Layer 1 back on. Press Cmd-Shift-E to flatten the layers, then crop the magenta strip on the right.
10. Graduated backgrounds
Next, we’re going to create an image with a separated figure, but with a background that has a graduated aspect for the depth. Turn the Quick Mask mode on and select the Gradient fill tool. Click and drag from halfway down to the bottom of the screen. The top half should be red.
11. Remove the background
Select the Paintbrush and set the hardness to 75%, the foreground colour to white and the opacity to 100%. Zoom in and use a large brush to remove the red mask from over the figure and, in our case, the fence, leaving the edges. Use short strokes that are easy to undo if you make a mistake.
12. Close up work
Reduce the brush size for removing the mask by the edges. Where the hair is fuzzy, reduce the brush hardness to 25%, then increase it again. Mistakes in the area where there is 100% red can simply be painted back over, ones where it is graduated have to be undone and reapplied.
13. Apply new layer
If you can’t see the edges of the figure, toggle it on and off for a better view. Also do this to make sure you haven’t missed any areas. Toggle the Quick Mask off to reveal the selection. Press Cmd-C to copy the figure. Create a new blank layer in the Layers palette and paste it in with Cmd-V.
14. Tidy up around the figure
Turn Layer 1’s visibility off and select the Background again. You now need to clone in over the left side of what was copied for Layer 1. This means the left side of the girl and branch and the under side of the fence. Use the Clone Stamp tool with a 100% opacity and 0% brush hardness.
15. Move into position
When cloning, extend the scenery without repeating textures and shapes. Next, click on the Channels tab and then the Green channel. Select the Move tool and move it to the left. Click on RGB to recombine and then toggle Layer 1 back on. Merge the layers and crop the band on the right to finish.
Bonus tip: How the 3D process works
Stereoscopic 3D works by having two separate images, one for each eye, that are spaced apart, so that when the brain combines them a sense of depth is created. Anaglyph 3D relies on one of the colour channels being positioned differently to the other two. There are three colour channels – red, green and blue – but you only have two eyes so two of the channels have to be combined. That’s why glasses are either green and magenta (a combination of red and blue), or red and cyan (a combination of green and blue).
To create 3D anaglyphs for red-cyan glasses, follow the instructions but replace all references to the green channel with red instead.