Article

Taking 3D with One Camera

With the exception of some Lenticular images all forms of 3D start with the same part, capturing 2 images.  Once we have two images we can present them in a variety of ways, and some software allows you to switch instantly between these when creating the 3D images. The methods of presenting 3D images are covered in the article 3D Photography Types,  with a wider overview of 3D in 3D Photography - An Introduction,  which in turn links to very many articles and projects.

Just about any item large or small can be photographed in 3D.

We can capture the two images, hand held with nothing beyond our camera, with a tripod and attachment, a prism arrangement to fit on the front or using two cameras. In this article we are concentrating on how to take images to produce 3D photographs using one camera. We are not here covering the prism attachments, but all of the other methods.

The objective in all cases is to take two images one from the perspective of each eye. With a normal looking lens length and, as long as we are not too close, this is about the difference between our eyes. The two images are parallel, not tipped in towards each other. So the camera just moves sideways between one image and the second.

The sideways distance between one photo and the next is called the Stereo Base and while its possible to keep this the same, you then have to limit the depth of items, keep to medium lens lengths and not get nearer than around 2 or 3 metres from the nearest items to you. When you work very close, as with macro, the stereo base may be only a couple of mm. See the article 3D Photography Stereo Base for a fuller explanation and details on free programs you can get to work this out for you.

One Camera or Two

We can photograph anything that is relatively still using one camera, but for live action 3D, for example catching a horse going over a jump or a steam train approaching us at speed, we will need to use two linked cameras. There are often more restrictions on what we can do when using two cameras. We have a second article looking at Taking 3D Images with 2 Cameras. 

What you need

3D images can be taken using just your camera, handheld if you want, you don't need to buy anything special, the software is free and 3D glasses are widely available and given away with video hire, some videos, some games, and occasionally in magazines and other ways, you can also make your own see our project Project - Making 3D Anagraph or Anachrome Glasses.

If you want, you can use a sliding bar or other attachments and a tripod, and this can be both easier to use and give a near 100% success rate.

Handheld Photos

You can take images that will be made into a 3D picture hand held. The objective is to just take two images, with the camera pointing parallel, not in or out and just moving it sideways between the two shots, the easiest way of producing a good success rate is:-

• Pick a distant item (infinity) and use the camera grid to put this on a known position for the first photo.
• Move the camera sideways only about the distance you need (Stereo Base ), and take another picture with the distant item on exactly the same grid position.
• iIn setting up the stereo photo in an editing package you can straighten the two shots and make some adjustments.

Ideally practice with this technique to get the hang of it, and gain the confidence to use it, even if you are normally planning to use a tripod and sliding arrangements or two cameras. The advantage of this method is that you can take 3D images anywhere and any when you have your camera with you. As each image is also a normal flat image, you can do this when you want as an additional option to the normal photos you are taking.

With Tripod and Sliding Arrangement

I prefer, when I can, to use the single camera and sliding arrangement, its far less to carry and simpler to set up than the two camera method and I can concentrate better on the image than when having to concentrate on keeping the shots parallel with the hand held method. I also have far more control over the Stereo Base   or distance the camera has been slid sideways.

There are a variety of sliding plates and focusing racks that you can get to allow a camera to be moved, most are used in macro photography. When selecting the one for you consider the range of movement you can get and how easy it is to use. You also need to see if there is any chance when you loosen anything of the camera falling off.  One example is shown in our article on the Novaflex Castel-Mini,   the important thing is that the camera has to stay looking parallel, so the device chosen must just allow a sideways movement, not movement in any other way, it especially does not want to go in or out. Simple sliding plates are quicker to use than the example linked to here, but this device has a number of uses macro, panoramas, as well as 3D, so is of more general use to me.

Some tripods allow the centre bar to flip to become horizontal and in theory you could slide this with the camera looking sideways, but the odd occasions I have tried this it has not produced results that did not require a lot of Photoshop work. I think this is because however careful you release and move things, its never quite parallel.

Using a device like the  Novaflex Castel-Mini,   the camera is put onto the rack so that the sliding mechanism allows it to move from left to right, level up the tripod and if you are able the camera as well.

You take the first photo, slide the camera sideways by the required amount and take the second photo. Its a good idea to always take left and then right, and to put a marker of some type between shots sets, it could just be a photo of your hand. Working  left to right you can always take several at different stereo base settings if you wish, but always start with left most and then take the images in sequence as the Stereo Base increases, so that after, although you may not know what distance you have moved it, you will know which is larger and smaller.

It's always worth taking two or three sets, because although you may not have noticed anything having moved, it may have, for example a bird or plane in one and not the other, taking several sets cuts down the amount of editing required.

Macro Photography

The stereo base is very small in macro photography, generally the closer you get the smaller the distance you slide the camera, down to extreme close ups where it could be a millimetre or two.  If you have something like the Novaflex Castel-Mini   this is easy to achieve as you can work out how many turns of the knob moves it a greater distance and then work out how much to adjust it to get the exact Stereo Base you require. If you can work with the camera on a tether and use liveview, so that you can have full control of focusing and see exactly what is happening. If you want to get extreme depth of field with macro then take a series of slices in the left position, then a series in the right, make up each of these slice sets to get the two images then use this to produce 3D. See Introducing Slicing and the pages linked to it, to get to understand slicing and information on the special software used.

This image was taken with a single camera, but time changed so the 3D effect
on the hands is not effective and you end up with two times shown.

Having taken the images

The same photos can be used to produce 3D images in any of the presentation methods. As new methods are likely to come about keep the separate images that make up the 3D image as well as the resulting images. The separate images are also normal flat images that you are used to and can be used generally.

You can get to most of the articles and projects in this section from 3D photography - An Introduction,  but the article that will be relevant, once you have captured your images, are 3D Photography Types,  Software to Make 3D Images, and possibly 3D Glasses, 3D photo frames, or 3D viewers for Side by Side Images.

See Also our 3D Section for more articles and projects on this topic.