Pedro Guimaraes, SOC ~ Life Behind the Lens

In my experience so far, the best tool for learning and understanding the intricacies of stereography is to simply start taking lots of stereo stills. Since it’s easy and cheap to do.

Hell you can even use your cell phone camera.

The idea is to start seeing what works and what doesn’t (then understanding why)

Since the first 3D photo was taking around 1840′s people has invented and patented literally thousands of ways and devices to take 3D photos.

The basic idea is that you need 2 images that are horizontally offset from each other.

SO the easiest way to do this with any camera without anything special,

1-Look straight ahead.

from now on DO NOT move you head!!!

2- put your camera viewfinder up to your left eye, take a picture.

now without moving your head….

3- slide the camera over until you can see the viewfinder in your other eye.
4- take another picture.

Voila! you have just taken a 3D image.

By not moving your head and just sliding the camera over to your other eye you have just achieved your 2.5″ interocular separation!

Unfortunately the problem with doing this is that you’ll never be level and you’ll have some rotation. Then you have to bring them into photoshop place them side by side and align them vertically to each other. You also have to rotate the image as well. Boom you have your left and right images.

Now a few tips.

usually I snap a pic of my hand in the shape of an L to kinda of “slate” the next 2 shots on my CF card as a stereo pair and the first one as the left image. Also get in a habit of taking the left image first so you never have to guess which eye the picture is.

The key to a good 3D image is that everything has to match. SO I recomend manual exposure mode. Same focal length, same aperture, same shutter speed. same everything.

To improve on this method, and make life alot easier.

Place the camera on a level surface to take the picture and slide it over. That way your pictures with always be horizontally aligned and have no rotation.

you should end up with a file that looks like this. (left and right have no rotational differences and are horizontally level)

You can do this a variety of ways. The most common is a “slide bar”. But you can do it with your tripod as well just by sliding the plate.

here is a” slide bar”

you can see it’s marked in millimeters so you can accurately alter your interocular separation.

there are lots of places to buys these.

but you can make one yourself. Here is a wood one.

Here is a Manfrotto “slide bar”

but for a bit more money you can have one that has geared action and is marked. “micrometer” style.

Bogen Manfrotto, micrometer slide bar.

here is the one I use,

So that’s great, your now taking 3D stills…..but as soon as you take a few of these you realize the first problem with the single camera/ slide bar technique.

It only works for “still life” ! Since if anything in your composition moves inbetween when you took the first pic and the second. Your shot is junk.

So this method works fine for taking pics of a parked cars, flowers, buildings etc….etc…..

But if you want to take pictures of moving things….a dancer, sports etc… you’ll need a rig with 2 identical cameras with identical lenses.

You’ll end up with something that looks like this,

“7 inch stereo base (hyper stereo)”

with DSLR’s

Mounted like this you get a closer to a 2.5″ inter-ocular with DSLR’s.

Okay now that you’ve read this far, I guess your interested. There is other options….a few companies actually make 3D Lenses for dslr’s like Loreo.

Of course there are many 3D purpose built camera built in the last 150 years

This is actually a prototype Fuji 3D digital camera with 3D LCD display.

Okay, now I know you next question is going to be what the deal with the separation between the cameras? (interocular separation)

This is what we call your “stereobase” “IO-Interocular” “IPD-Interpupilary distance”

When using two cameras there are two prime considerations to take into account when taking stereo pictures; How far the resulting image is to be viewed from and how far the subject in the scene is from the two cameras.

How far you are intending to view the pictures from requires a certain separation between the cameras. This separation is called stereo base or stereo base line and results from the ratio of the distance to the image to the distance between your eyes. The mean “interpupillary distance (IPD)” is 63 mm (about 2.5 inches), but varies with age and gender. The vast majority of adults have IPDs in the range 50–75 mm. Almost all adults are in the range 45–80 mm. The minimum IPD for children as young as five is around 40 mm.

For example if you are going to view a stereo image on your computer monitor from a distance of 1000 mm you will have an eye to view ratio of 1000/63 or about 16. To set your cameras the correct distance apart you take the distance to the subject (say a person at a distance from the cameras of 3 meters) and divide by 16 which gives you a stereo base of 188 mm between the cameras.

If you intend to view the stereo image from the same distance as it is captured (e.g. a subject photographed three meters away, projected on a movie screen at a distance from the viewer of three meters) then the stereo base separation will be the same as the distance between the viewers eyes (about 63 mm).

[B]VIEWING[/B]

In this forum we really only have 2 options,

Red&Blue Anaglyphs ( Yes like in the 50′s)

Viewing anaglyphs through appropriately colored glasses results in each eye seeing a slightly different picture.

In a red-blue anaglyph, for instance, the eye covered by the red filter sees the red parts of the image as “white”, and the blue parts as “black” (with the brain providing some adaption for color); the eye covered by the blue filter perceives the opposite effect. True white or true black areas are perceived the same by each eye. The brain blends together the image it receives from each eye, and interprets the differences as being the result of different distances. This creates a normal stereograph image without requiring the viewer to cross his or her eyes.

Here is a tutorial how to make anaglyphs from you L&R images.

You can use the same method to create the “colorcode” just use correct color.

ColorCode 3-D (blue-amber method) a.k.a [B]superbowl glasses[/B]

ColorCode 3-D is a relatively new, patented 3-D Stereo system. It is advertised to improve color and depth information over traditional Red/Cyan or Red/Green Anaglyphic 3d. It uses the somewhat odd colors of Yellow and Dark Blue on-screen, and the colors of the glasses’ lenses are Amber and Dark Blue. The Amber lens, however, lets in a little bit of every color on the spectrum, causing for heavy shadowing when viewed at close range. It is not in common use, and has yet to become a mainstream system. Images viewed without filters will exhibit blue and yellow fringes, but will otherwise appear with better color rendering than that seen when viewing red-green anaglyph images without filters. The method also employs computer image processing to reduce fringing at extreme depths.

Basically it’s the same method, it just uses a different color spectrum to isolate your eyes. It has some advantages over R&B.

Important to point out the “colorcode” actually does do some proprietary “processing” to improve it further. So it’s not true colorcode unless they encode your image. SO the colorcode I create works fine, but if they encoded it it would be better.

Here some RED & BLUE anaglyphs

Pretty much every picture taken in space has been stereoscopic.

Red+blue glasses