From 2D to 3D

January 01, 2011 — Ever wanted to make a 3D image without the complications and expense of stereoscopic photography? Well here is how we can get from 2D to 3D with a bit of control requiring (in this case) Magenta/Green 3D glasses to see the final effect.

It all starts with a depth map. What do I mean by depth map? Well, it’s a graduated grayscale map showing the planes where we want our image to appear.

Black would push all associated pixels to the very back, while white would pull them to the front, leaving every shade of gray to effect the image proportionally.

This is where all of the control is—and where we can determine what part of our image will appear on what plane when viewed through the 3D glasses. Cool right?
How do we make the depth map? There is no one way, but here is how I like to get it done: Use the Paths panel and draw pen paths around the areas determined to be pulled (white) or pushed (black).

Once all of the paths are in place, select a blank layer and one-by-one make the path into a Selection and fill it with the associated tone.

To give the appearance of things gradually pulling forward or pushing back, apply a Gradient Fill—black to white or white to black. Another trick is to create the depth map (like we are painting) and work from the background to the foreground. (Remember black pushes all the way back and white pulls all the way forward.) Here is where we need to practice to achieve the best results. It’s best to start simple and work from there.

Once we have the tonal map on one layer we can fix big holes by painting them in with a brush in grayscale. We then duplicate this layer as a new document and apply a subtle Gaussian Blur to smooth the transitions between tones. I know “subtle” may not be specific, but just make the transition smooth. Like I said before, this will be a bit of trial and error.

Once we have this depth map save it as a .psd file and name it so we can identify it; we will use it in a moment. Now we open a flat version of the file we wish to make 3D. Go to the Channels panel and highlight the green channel and go to Filter>Distort>Displace. Here we will see a dialogue box asking how much displacement takes place on both the horizontal and vertical plane.

Enter 10 on the horizontal plane, 0 on the vertical and leave the other settings as is. This number may require minor tweaking as it will be image dependent and require smaller numbers for lower-resolution files. Now point to the file to displace the channel against by selecting the depth map we made earlier. Voila! If the effect is too much then reduce the displacement to –8 and 0 and adjust accordingly.

My video tutorials are located at www.vimeo.com/chrisalvanas.