You can photograph the moon in 3D by taking one picture before dawn and the other after dusk. This way the distance the Earth rotated during that period becomes your baseline. You then align the two images in Photoshop and crop them.
The Cyclopital3D Base Extender uses mirrors to increase the stereo base of a Fuji Real 3D camera to almost 9 inches (225mm). This lengthening of the stereo base allows you to get 3X further away from your subject while still maintaining an acceptable level of parallax. The Cyclopital Web site at www.cyclopital3d.
has a downloadable user manual.
Talk about baselines! NASA's STEREO (Solar TErrestrial RElations Observatory) mission has two nearly identical observatories - one ahead of Earth in its orbit, the other trailing behind. The Web site has a gallery of 3D images captured by these cameras on the satellites
Click here to download an Excel spreadssheet you can use to calculate the time interval between shots.
A stereo pair taken out of the left side of a moving vehicle are taken in the right order. Those taken out of the left side are reversed.
Hyperstereo refers to increasing the baseline to capture enhanced depth in more distant scenes. To calculate the base you divide the camera-subject distance by 30 (1:30) although some people like a shorter base and divide by 50 (1:50). In either case, because the base is so long, you have to take the two photos in a stereo pair at different times, perhaps using a slider bar or other technique to move the camera horizontally between shots. This is true even of a twin-lens stereo camera such as the Fuji 3D cameras that have menu settings you use to trigger the two shutters separately so you can move the camera between shots. Since baselines are somewhat controversial try taking second shots at different distances and then pick the best pair later.
To capture depth in a distant scene you have to lengthen the baseline so it's 1/30th the distance to the subject.
3D FROM PLANES
When photographing from a commercial airliner:
- Sit in front of the wing if you don't want it in your pictures.
- Try to sit on the side away from the sun—for example, the right side when flying east to west and on the left side when flying west to east. Shooting into the sun will just create a great deal of glare and highlight imperfections in the window.
- Shoot a number of images because results are unpredictable as the plane bounces along.
- Try a range of intervals between shots. The faster you are moving, the shorter the interval.
- Clean the inside of the window, turn off the reading lamp, and wear dark clothing to reduce reflections.
- Zoom out because vibrations will be more obvious if you zoom in.
- Photograph through different parts of the window since they often have dirt and scratches on them.
Moving the Camera between Shots
With Fuji's INDIVID
. SHUTTER 3D
setting discussed in the previous section, you can manually take two shots of the same subject from different positions, and the camera automatically saves the images as a single MPO photo. After the first image is taken, it appears as a transparent overlay on the monitor to help you align and frame the second shot. You can also achieve this same end using a single camera handheld, mounted on a tripod, or mounted on a slider bar.
- Slider bars are often used for hyperstereo but have their limitations for distant scenes. For example, if a mountain is one mile away, you would need a slider bar that's 176 feet long (5280 ÷ 30). Since this isn't practical you have to do the best you can.
- A distant object, such as a mountain or cityscape, can be captured with several feet between pictures. One way to do this is to set up two tripods so you can just move the camera from one to the other and everything has been prealigned. You can also have two people take pictures at the same time
from two different positions to capture slowly moving subjects such as clouds but if the cameras are not identical you may have problems with colors, exposure, image aspect ratios and even lens coverage.
- You can use this principle to photograph the moon. To do so, you take one photo in the morning just after it rises and the second in the evening just before it sets. Between the two shots the moon has moved far enough in its orbit around the Earth that you have a substantial baseline.
Oliver Sacks describes making a hyper stereoscope when young that let him see the world with a longer baseline than the distance between the eyes. Page 112 in The Mind's Eye.
Shooting from a moving Vehicle
Using Fuji's INTERVAL 3D SHOOTING
setting discussed in the previous section, you press the shutter button once and the camera takes the first picture, pauses for the specified interval and then takes the second. This is the ideal setting for shooting from a car, train or airplane because it uses the distance you travel during the specified interval to establish the baseline.
- Aim the camera out the window perpendicular to the direction of travel and take two pictures with a short interval between them. The interval between shots depends on how fast the vehicle is traveling. In a car you just have to look at the speedometer. In trains, you may have to guess. In planes the takeoff speed is normally around 150–180 mph and gradually increases as the plane climbs. It eventually reaches 550–600 mph or so at altitude. Knowing the vehicle's speed you can then calculate a time interval between shots using the following spreadsheet.
Fuji's Real 3D cameras can be set to take the second photo after a specified interval. If you are lucky you'll get some great shots of towering cumulus clouds.
This table shows you how to calculate an interval between shots and is also available on-line as an Excel spreadsheet. Click the button to the left to download it.
- When you have distinct and slowly moving clouds in your landscapes and cityscapes, move the camera between shots in the direction opposite to their movement. This makes the clouds' parallax greater than the unmoving parts of the scene—making them appear closer.
- To increase the baseline for cloud photography you can photograph them from a moving vehicle with a short interval between the two exposures. Try to avoid capturing closer subjects in the foreground.
- If you are using a Fuji Real 3D camera take a number of stereo pairs using different intervals because the results are somewhat unpredictable.
- If you are using a single lens camera with a continuous mode, use it to capture a series of images. Later you can see which pair gives the best results.
- Avoid having foreground objects in the images as much as possible because they can be very distracting.
- Consider your direction of travel and its effects on which image in a stereo pair is taken first. For example, if you photograph out of the left side of the vehicle using the Fuji's default setting, the left eye image is taken first and then the right eye image is taken. This is the same order in which you will view the pair. However, it you photograph out of the right side, the right eye image is taken first and then the left eye image is taken. If you view a pair taken out of the right side they are displayed on the camera's monitor in pseudeostereo. You can reverse the images later in a photo-editing program, but it's easier to change the order in which the pair is stored in the MPO file so you can see the true 3D effects on the camera's monitor. To do so, on the Fuji Real 3D cameras you use the TURN command.
Clouds over the landscape and the shadows they cast make good 3D images.
Photographing geologic features, such as these snow covered mountains outside of Los Angles, can give a dramatic 3D effect.
City skylines, like Boston's, taken during takeoff make good 3D subjects.
An anaglyph image taken during takeoff from Boston's Logan Airport. Since the plane is still so close to the ground, the image is still easy to fuse even with the jet engine in the foreground.