How to Make 3D Images
Photoshop® Version
The art of producing 3D images is an evolving process for any artist. I won't pretend to be an authority on the subject, as in fact my terminology is for now quite weak. If you're more knowledgable than I in any of a number of ways, please be tolerant. I can only speak from my own experience, having worked several hundred images. I welcome comments and additions of others in the 3D image producing community to the knowledge base I present here.

This page is dedicated to the production of 3D digital images, which can then be displayed online and/or in printed form. As such I won't be addressing other common or traditional styles of producing 3D images. I will briefly address how to shoot 3D photos, then how to process them on a computer. This tutorial is addressed at the artist using a single lens digital or film camera, or two mounted digital cameras. If you are using a stereoscopic camera, there may be some valuable information here, but I'm completely ignorant of their overall benefits and limitations.

I use mostly PhotoShop® for processing the images. StereoPhotoMaker (available as freeware), and PokeScope® offer software made specifically for producing 3D images, with many extremely useful production and presentation options.

Aside from the software, by far the best overall tool you'll want for producing 3D images is PokeScope®'s 3D viewer, which will let you view side-by-side 3D images either on your computer screen or in any print size. The best thing about having one when producing 3D images is that instantly you'll see whether an image is working or not, while you're working on it. I produced many satisfactory printed 3D images before I discovered the PokeScope® viewer, but having obtained one, there's no turning back. To my knowledge it is currently the best product our there for viweing side-by-side 3D images on a computer screen.

Shooting Your Pictures

This tutorial is geared primarily for someone shooting still-lifes with a single digital camera, or with two mounted digital cameras, but it certainly applies to someone using a single lens film camera. If you're using a film camera, be sure to opt to also receive digital images when you have your film processed. Scanning photos for this purpose adds a level of lost quality and consistency.

Consistency is the key when shooting 3D images. There are always two images to a 3D image, one taken from a "left" perspective, one from a "right" perspective. I always take the right-side shot first, then the left. Some artists do it the other way, first left, then right. It doesn't matter which you choose, but it's important to be consistent, so that based on the assigned file number of the shots, you'll always know which is the left shot and which is the right.

Using a tripod is extremely helpful, but not really essential. Using both a tripod and slidebar will make processing your images much easier, and your success rate much higher. Even so, it's not always practical to carry a large tripod with you, and small ones are often not suitable for the circumstances of what you're shooting. I've done a great number of handheld 3D shots both with and without a tripod or slidebar. Even so, I always appreciate the ease of processing shots taken with greater care and consistency.

I like to take the right shot, hold the camera very still until it is ready to take another shot, and then re-position the camera for the left shot. In each case I focus on a single spot for both shots, and aim camera to a single (perhaps different from focus point) spot for both shots. General rule of thumb for re-positioning the camera right-to-left (or left-to-right) is 1/30th the distance to your focal point (i.e. for a primary subject 10 feet away, 1/30th of 10 feet is 1/3 of a foot, or 4 inches). Some artists prefer a 1/50 ratio. Of greater importance is to take care to keep the distances from the camera to the focal point and subject of your photos consistent. If you have a natural horizontal reference in your picture (i.e. a waterline or rooftop), you can use it your advantage, especially for lining up two hand-held shots.

After taking the two photos with a digital camera, you can scroll back and forth to review the two shots immediately. The best indication of a well shot pair is that when scrolled back and forth you'll notice only a slight rotation of the subject/s.

Keep in mind that you need subjects that don't move, or move much. Wind can make taking good 3D shots extremely difficult. Tiny leaves and narrow vertical objects are often difficult and unrewarding 3D subjects.

Macro (extremely close) shots of flowers and other objects can be glorious. Even so they're more difficult to process, because even very small differences between the two shots in distance to the subject will produce significant differences in image size of the subjects, and resizing one image to match another can be challenging.

Preparing to Process the Images

After downloading the images into your computer, you will probably want to rename them to more easily recognize them when bringing them into PhotoShop®. Again, consistency is important and will save you time and bother later on. I like to label them with a name that tells me where they were taken or what they are, and then add a -OL or -OR to the name (i.e. PineTrees-OL and PineTrees-OR), telling me it's the original left or original right image. The form you choose is unimportant, so long as you develop a consistent style that works for you.

In using PhotoShop®, it's best to create template files that you can use over and over whenever you want to create a new 3D image. I'll gladly share the templates I use with you. You're welcome to use them as they are, or modify them to work better for you.
   Click here to download a two-image template for processing the left & right 3D images.
   Click here to download a single-image template to transfer and save the individual left & right images, once produced.

Processing the Images

Once in PhotoShop®, open (File, Open) the two-image template. Next open the left and right files for the image you want to process. (Note: you can open all three of these at the same time if they're in the same folder. Click on one, and hold down the {Ctrl} key while clicking on the others). Drag the left image to the left side of the template. It should reproduce itself there, likewise with the right image to the right side of the template. You can now close the left and right original images. Depending on the size of the images, they will take up either a small part of the template, most of it, or will considerably overextend the template.

There are two main, touching, adjacent left and right areas within the guidelines of the template. It will become your task to fill these areas completely with two nearly identical images. You will manipulate the two images to reach to the edges or more likely overextend these areas, and will then crop them to the guidelines to exactly fill these areas.

I'll assume you currently know about as much about PhotoShop® as I did when I taught myself to make 3D images in it, which was almost nothing. Likely on your the left hand side of the screen you'll find a vertical "toolbar". If you don't see it there, click above on (Window, Show Tools). You'll also need the Layers dialog box. If it's not open, click on (Window, Show Layers). Drag the Layers dialog box toward bottom right. You'll need to be able to use guidelines, which means you'll need to have rulers showing on the template. If there are not rulers at the top and left of the template, click (View, Show Rulers). Click once on the top bar of the template, then click on (View, Fit on Screen). This should enlarge the template for easier viewing, or at worst leave it at its current size.

It's important to understand that in working with the two (left and right) images, sometimes you need to perform a function on the two images simultaneously, and at other times you need to modify one image, leaving the other alone. Be thankful that there's an Undo command (Edit, Undo), because you'll probably need to use it frequently. Each image represents a "layer". Altogether there are three layers (one is the background, which is blank). If you look in the Layer dialog box, one of the layers is always selected, and that's the one at any given moment you're working on. Clicking on a photo does not change which photo you're working on. Clicking on a layer in the Layers dialog box does. To perform functions (i.e. resize) on the two layers (images) simultaneously (both at the same time), you'll need to link them. After layers are linked, to perform functions on only one layer at a time, you'll need to un-link them.

Suppose Layer 1 is hightlighted in the Layer's dialog box (if you first dragged the left image up, then the right, the left image is Layer 1, the right is Layer 2). To link them for simultaneous modifications, check the box in Layer 2 to the right of the eye symbol. A chain symbol will appear, and now whatever you do to Layer 1 you'll also do to Layer 2. This includes repositioning (moving) the images, resizing the images, rotating the images, etc. To un-link them, so as to work on the images independently, click on the chain symbol, and it will disappear; they will be un-linked.

Next your goal will be to line up the two images so that they are positioned vertically as identically as possible. I will assume that the image sizes of the two images are the same. If you were at the same distance from the subject in both shots, and didn't change the zoom, the subject/s of your images should be practically the same size on the two images. Note: macro shots often need to be first resized, but you'll need to experiment and play with this on your own.

For the moment suppose that you'll leave the left image as it is, and manipulate the right image to line up with the left one. If you've linked the two layers, un-link them.

Look for two clear reference points (spots on each photo that can be seen clearly on both images). These two points should be well seperated horizontally from each other (i.e. one toward the left side of the left image, one toward the right side of the left image). Choose the pointer tool on the toolbar (top, right, looks like an arrow) and drag horizontal guidelines down to pass through these two reference points on the left image (to drag down a guideline, place the cursor onto the top ruler, click and drag down - later you can click on a guideline, and drag it back up to the ruler to get rid of it). Select the layer of your right image on the Layers dialog box (if you don't know which one it is, click on and drag an image and see which one moves, there's always the undo option). Select the pointer tool, and move the right image until its left reference point lines up vertically with guideline that goes through the left reference point on the left image. You may notice a difficulty in lining them up, in that the top or bottom of the image you're moving may "want" to keep aligned with a guideline. To stop this from happening, click on (View, Snap to Guides). This is an on-off, checked or unchecked option, telling PhotoShop® to grab the edges of an image onto guidelines if they're close. Later on when croping the photos, it's essential that it be turned on, but when lining things up, you generally want this option unchecked (off).

Now that the left reference points of both images are lined up vertically, what about the right reference points? If they are perfectly lined up, great. This is where you'll be glad if you used a tripod to take your photos. If one is higher than the other, the next step will be to rotate the right image so as to be able to get the to images to register vertically the same on the two reference points. This is done by clicking (Edit, Transform, Rotate). By making small adjustments in rotation, and then vertically repositioning the right image, you should eventually get the two to match up on the guidelines.

Using guidelines is only one of a number of techniques available to line up images. Another option is to bring up a grid, click on (View, Show Grid). Grid lines can be effectively used for lining up the images. Another excellent techinque is to temporarily modify the Opacity of an image. In the Layers dialog box Opacity defaults to 100%. Modify it to 50% (more or less OK), and then when you drag one image over the other you will see a phantom of one image over the other, making for a fairly easy lining up of objects. After your vertical positioning is correct, change Opacity back to 100%.

Note: you may find that the translucent image drops behind the solid image, and need to indicate that the translucent image go in front of the solid image. To do so click above on (Layer, Arrange, Bring to Front). Bringing a layer to front or back is helpful in many other manipulations.

Next you'll want to link the two images (see above) and resize them together so that each image takes up at least as much space as the main areas of the template, or more likely each image extending beyond the spaces. Move the left image as you wish so it is framed nicely within its template area. Look to see that the right image will also at least cover its template area without leaving blank areas at the top or bottom. Now you're ready to crop the images.

Make sure that Snap to Guides is checked (View, Snap to Guides). Un-link the layers (chain symbol disappears). Choose the layer for the left image. Select the cropping tool on the toolbar (square, dotted symbol, top left). Place the cursor on the top left guideline of the template, click on your mouse, and drag the cursor to the bottom center guideline of the template. Click above on (Layer, Add Layer Mask, Reveal Selection). The left image should be cropped to the template guidelines (if the wrong image gets cropped, choose (Edit, Undo), select the other layer on the Layers dialog box, and repeat (Layer, Add Layer Mask, Reveal Selection).)

Choose the layer for the right image. Change its opacity to 50%. Select the pointer tool, hold down the {Shift} key, and drag the right image over the left image so it matches up as horizontally closely as possible (holding the the {Shift} key when moving an image will keep it's movement in a straight line, either vertically or horizontally). The two images should already be lined up vertically, but if not, line up the right image vertically again to match the left image. Again, select the cropping tool, place the cursor on the top left guideline of the template, and click and drag the cursor to the bottom center guideline of the template. The right image (for the moment in the left spot) should now be cropped to size. Hold down the {Shift} key, and drag it to the guideline on the right side. Change its opacity back to 100%. If you have a PokeScope® viewer, you will be able to see your 3D image in all its glory, and know if it's going to work as a good 3D image.

Click on (File, Save As), and choose a name for the image. It will be saved as a PhotoShop® .PSD file (i.e. PineTrees.PSD). Your can go back at any time later and rework/modify the images in this file. No information is lost. You can knock off the layer masks (cropping) you've done, and perform any further reworking of the images you may wish.

Processing the image from this point forward is a matter of choice. You can quickly produce a single .JPG file of the two side-by-side images (File, Save a Copy) select JPEG in the Save As box, enter a filename (i.e. PineTrees, resulting in a file named PineTrees.JPG). Initially save these in PhotoShop®'s best image quality (level 12).

There is also a way using the channel options in the Layers dialog box to turn the image into a single anaglyph image, although I don't know exactly how to do that. Hopefully someone who does will read this and offer the technique.

From here I typically open the single-image template. Select the pointer tool, and drag the left image into the single-image template. If properly cropped to the margins in the two-image template, it should fit exactly. Nudge it into place. To save the left image (File, Save a Copy) enter a filename (i.e. PineTrees-L.jpg) and select JPEG, best image quality (12). Then remove that image from the single-image template (Layer, Delete Layer). Click on the top of the two-image template, select the other layer, drag the right image down into the single image template, and repeat the save process, labeling the saved file (i.e. PineTrees-R.jpg).

From this point you have a lot of options, depending on what you're trying to do. If you have StereoPhotoMaker or PokeScope®'s software, you can bring in these two images, manipulate them in a number of ways, and produce them into an outstanding online or print format, print them, or save them in side-by-side or anaglyph format as a single bitmap or .jpg file.

You can later go back to PhotoShop® and re-size these files to fewer pixels (or inches), or re-save them into a different filename or location, or with a lower image quality for faster sending or loading.

If you have any questions or comments about this tutorial, feel free to email me at info@3dDigitalPhoto.com, and I'll try to help if I can.