Text and pictures © 1993-2021 Guillaume Dargaud
Last updated on 2018/10/17
"Adventure is just bad planning." — Roald Amundsen (1872—1928).
Those pictures look normal, don't they ? Well, they are not normal pictures. They are supposed to be viewed through red-cyan glasses. The left eye covered by the red filter and the right eye covered by the cyan filter. This way you should see a 3D effect.
I took those pictures with a homemade lens. I had an old Sigma zoom 35-70/3.5-4.5, my first cheap lens, that was somewhat damaged after falling on the floor. It did not focus well in AF anymore. So I bought a new one and decided to do some modifications on the old one. I inserted two half filter, one red one cyan, as close as possible to the optical center of the lens (near the diaphragm, see diagram on the left). Nothing extraordinary about it. You just have to be careful while taking the lens apart, don't leave fingerprints on the lenses or the electrical contacts and don't force anything. All I used was a set of small screwdrivers and a pair of small scissors to cut the filters I'd taken from a pair of glasses from a magazine.
But wait ! Most of the pictures of this kind I've seen before were monochrome ! That's because they were taken from 2 separate pictures, shifting the camera position by a couple cm, and then doing a print by mixing the images through 'perfect' filters. By perfect filter I mean that all color besides red and cyan is removed. Since my lens has two half filters of complementary colors, the resulting picture is of a normal color. Indeed, objects in the plane of focus are unchanged. Objects that are too close will have some funky light separation going on: the part of light it that went through the red filter will appear shifted to the left (and resp. the cyan to the right). When you look at the pictures through the glasses, the left eye (red filter) can see only the cyan image that's on the right, the right eye sees the red image on the left, making you cross eye. Bingo, that's 3D.
There are many ways to display 3D-like images: anaglyphs (red-cyan glasses), stereoscopy (one small image for each eye), diversely polarized images for each eye (won't work on a monitor or on paper), temporal multiplexing (guaranteed headache), lenticular screens (like gifts in cereal packs, quality can be OK if distances are optimized), holography (very difficult, no color, expensive) and those stupid stereogram dots that are in fashion now (I've never been able to see anything in them).
The anaglyphic technique is one of the easiest and cheapest way of taking and viewing 3D color pictures. It's rather easy to build a lens and glasses are usually found in magazines every once in a while (recently articles about the Titanic and Mars Pathfinder were published in National Geographics with such pictures). Otherwise you can purchase various types of anaglyphic glasses off the internet.
There's no particular precautions to take while shooting the pictures, just be sure to take horizontal shots, so as to have red on the left and cyan on the right (otherwise it'd be up and down and make no sense to the brain in charge of reconstructing the third dimension). In my experience, for better 3D effect you should apply the following 'rules': always use the lens at full aperture (the 3D effect is visible only on objects that are out of focus; if you open at 22, everything will be in focus); and make sure you have objects in the background and the foreground (this goes against normal photographic rules). The resulting loss of sharpness is compensated by the stereo effect.
The principle of anaglyph presentation of 3-D images was first proposed in 1853 by Rollmann, but adapted to practical use by Ducos du Hauron in France only in 1891.
Above: A chick asking for dinner by doing his usual 'Piu! Piu!' cries.
Right: Here a picture of a penguin chick feeding directly from the mouth of the parent.
Notice that the effect can vary a lot from picture to picture ? I've never used this lens very much because I did not have 3D glasses. But now that I've bought a bunch of them on Internet, I may start using it again...
You can order those glasses on the web at several different sites like stereoscopy.com. There are many sites with anaglyphic images on display on the web, one of the best is the Mars Pathfinder site.
The paint you see on those poor penguins was set by the ornithologist for the purpose of identification. Otherwise it's impossible to tell the difference from one to another. With a little experience it's possible to tell females from males from their voice pitch, but that's about all.
Right: Two Weddell seals bathing in the sun near the airstrip.
Do you want a lens like that ? Well, you can either make one yourself or you can try to find a second-hand Vivitar Qdos lens. It was a 70-210 zoom with those filters inside and a switch to activate them.
Left: 3 ornithologists are catching skuas to measure and weight them, and to put numbered rings on those without. A carcass was set on the ice to attract them and then it was a hilarious lasso party against those intelligent (and aggressive) birds.
Right: A skua, just captured with a lasso, in the hands of the helicopter pilot !
Have you seen my normal pictures of Penguins ?