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Project - 3D Two Camera Portraits with Flash

This is a far more complex project than the others we have looked at on 3D, if you haven't already try the others first, before you attempt this one.

This project will not be possible for many just because they don't have access to the equipment required, but even if you cannot do it, understanding how it works should be of interest if 3D photography interests you.

This project involves taking live action 3D, to achieve this we need two matched cameras that can be wired together. We cannot take 3D photos of moving items with a single camera. The second complication is that we are going to take the photos using flash, so we need both cameras to have their shutters open when the flash goes off. Once you have mastered this and the other projects in this series you should be able to take any 3D photos you want.

In order to do this you will need:-

• 2 matched cameras with similar lenses of the same focal length.

• A tripod and bar to support 2 cameras (or two tripods, but this is more tricky to set up).

• A cable that will connect the cameras so they will fire at the same time.  See Cable to parallel 2 cameras.    If you don't have and can't find a  special cable you may be able to get someone to knock a suitable device up for you that triggers both cameras on its normal cable release. If you do get someone who understands electronics and can, put in some diodes so you don't get any direct connection between the cameras that might damage their electronics. If in doubt at all don't do it.

• A compatible flash unit or several.

• Access to a computer to work out the 3D Photography Stereo Base.

• Software to put together the 3D image (Anagraph others call it Anachrome),

• 3D Anagraph/Anachrome glasses, we also have another project to make a pair of these.

The process is:-

1. Set up the portrait as you would any other.

2. Work out the settings as if we were taking a single photo with one camera.

3. Work out the Stereo Base.

4. Set the cameras on manual.

5. Take the image and check it worked.

6. Put the 3D image together in software.

I suggest that you set up the portrait environment with flash units, reflectors, backgrounds etc exactly as you would normally. See our Lighting and Reflectors Section for more details on these items.

Set up the tripod and dual camera bar and put on both cameras. The cameras need to be parallel and pointing exactly parallel or as parallel as you can.  I have discussed how to do this in Taking 3D Images with 2 Cameras. 

Use one camera only and set up the exposure, check you have the depth of field and take a test shot.

From the settings you have and the distance to your subject you can work out the stereo base, see 3D Photography Stereo Base   for more on this. This is the distance you need to have between the centre of your two camera lenses. Its also the distance from the right of one lens hood to the right of the other, which is easier to measure.

You can now connect the two cameras together with a special wire, and you need to set both cameras on manual and the synchronisation of the flash so that both shutters are open when the flash fires. This is covered in Taking 3D Images with 2 Cameras. 

You are now, in theory, able to take 3D portrait photos. Take one and check you have two images that have registered the flash, and then go on and take a number of others. I would suggest you put a marker in the shot every so many photos this could simply be someone holding up a card. You will find this makes it far simpler to match up pairs of shots and to sort out any problems that have occurred.

Putting the 3D images together is exactly the same process as with the other projects.

The problems you are likely to encounter are just the technical ones of cable connections, both cameras firing, cameras having their shutters open while the flash goes off and the need to keep the two with the same settings.

If you are getting flash synchronisation problems just stop and draw some little diagrams for yourself of what the different cameras are set on and when in this sequence the flash will go off, and you are likely to see a solution.

What have we achieved

You will have discovered that operating two cameras together and getting the ideal results is a lot more difficult than twice that of a single one, but hopefully you will have some 3D live action photographs.

Maybe with this experience behind you, you may decide to take on live action 3D in a faster less controlled environment, how about steam engines or equestrian topics.

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