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< Product Resources
Introduction To Panoramic Photography
 
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Many photographers are captivated by the unique perspective that panoramic photography affords, allowing the creation of pictures that mirror the mind's eye more than traditional photographs. One can use a "normal" panoramic camera to accomplish this such as the Hasselblad Xpan or Fuji GW617. But these cameras, while certainly able to produce stunning results, aren't actually rendering the world in the way that your mind sees things. To do this traditionally, a curved film plane was needed, such as in a Noblex camera. By having the film a fixed distance from the optical center of the lens across the entire frame, illumination and sharpness are ideally optimized for the whole image and not just the center.
But there is an alternative method of achieving the perspective of a curved film plane while using a camera with a flat film plane. This is accomplished by stitching together individual images taken from one location with one lens. While this can be done with a normal tripod head with decent results, to achieve truly professional images you'll need three ingredients:
· A level axis of rotation
· An identical amount of rotation for each shot
· An isolated rear nodal point
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The rear nodal point is the spot within the optical path where all of the light rays converge. In actuality, there are two nodal points within the optical path-the front and rear nodal points. It is possible for these points to be outside the dimensions of the lens itself while the location of these points varies by the lens design. If you have the camera upon a level tripod with the rear nodal point directly over the rotation axis and an even amount of rotation with each shot, you could stitch together seamlessly subjects as difficult as a brick wall.
When a symmetrically designed lens is focused at infinity, the rear nodal point is always located in front of the film plane at a distance that is identical to the true focal length of the lens. For example, a lens marked as 50mm may actually have a true focal length of 45mm. If the distance between the film plane and the lens flange was 35mm, then the rear nodal point would be located exactly 10mm forward from the lens flange when the lens is focused at infinity. Occasionally there are telephoto lenses that are physically shorter than their true focal length, and in these cases the rear nodal point may be in front of the lens.
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  Isolating the nodal point can be easily done by using a dedicated tripod head for this task, such as the
Bogen 3415 head or a Kaidan Kiwi head. These are the most effective solutions for isolating the nodal point. But it is also possible to isolate the nodal point without having a dedicated tripod head exclusively for this task. All panoramic heads offer left-right & fore-aft movement of the camera upon a panning base. You could use a macro sliding rail on top of a tripod head with a panning bed, or a combination of two long quick release plates over a panning base. Both of these solutions are more economical than a dedicated panoramic tripod head, but they do not put the camera in the vertical orientation. If your camera is like most and has a "landscape" format (where the longer base is on the horizontal axis), you would need an "elbow bracket" such as the Bogen 3288 or the Slik L Vertical Bracket in order to position the camera in the "portrait" orientation. By doing this you'll get a "taller" panoramic, and thus have more image area and sharper photographs. When adding the cost of an elbow bracket into the mix, the savings from creating your own panoramic head are minimized.
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If you don't know the location of the film plane in your camera, or the actual focal length of the lens, it is still possible to achieve an isolated nodal point. To do this, first put the camera on a tripod-and make sure it is level. At minimum, you will need a tripod head with a rotating pan bed (this can be as simple as Novoflex's Panorama Plate & the ability to slide the camera both left-right & fore-aft upon the top of your panning base. By viewing the camera from in front of the lens, use the left-right movement of your macro sliding rail or quick release plate to center the middle of the lens directly over the middle of the panning base. This is a relatively easy thing to do just by sight. |
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Next comes the harder part, determining when the rear nodal point is isolated through fore-aft movement of your sliding rail or quick release plate. You'll be able to tell if your rear nodal point is isolated by observing through the viewfinder the relationship of vertical lines and rotation. Position the camera so that two vertical lines at different distances from the camera are aligned. Examples are the edge of a building with a telephone pole, two pens on a table-whatever you can find. Experiment with the fore-and-aft placement of the camera upon the panning base until you find a position in which the spatial relationship of the two vertical subjects doesn't change as you rotate the camera.
(Insert nodal 1 thru nodal 4 here, labeling nodal 1 "picture 1" etc.) Pictures 1 and 2 show the result of panning while the nodal point is properly isolated. Pictures 3 & 4 show that the relationship between the brick wall and telephone pole have changed due to rotation of the camera-the rear nodal point isn't properly isolated.
PICTURE 1 |
PICTURE 2 |
PICTURE 3 |
PICTURE 4 |
It may take awhile, but every lens has such a spot. It is a good idea to mark the positioning points on the quick release plates or sliding rails so that you can quickly assemble the tripod in the future. The same process is accomplished by dedicated panoramic tripod heads much more quickly. Kaidan offers many tripod heads for specific camera applications, and these heads will indicate where to position the camera without the need to undergo the trial and error process of nodal point isolation. In addition, the dedicated tripod heads usually offer detented rotation of the panning axis to further ensure accurate, repeatable rotation amounts. This is not necessary, however, as one can simply observe how many degrees of rotation move the lens view 80% and use that as a base of how much to move the camera for each shot.
Once you've isolated your nodal point, you can take individual pictures and assemble these prints together with an adhesive to form one large image. They should line up quite well if you've accurately placed your camera over a level axis of rotation. If, however, you desire a seamless union of the pieces, you will need a software program that can handle this task. There are several different programs, for both Mac & PC users, that accomplish this-and all of them will require a film scanner (if you're not using a digital camera) in order to bring the photos into the computer. By employing the software, you'll be able to upload the individual images and have the computer program assemble them into one unified photo. Some software programs are a bit more forgiving than others, but they'll all benefit greatly from having an accurate position of the nodal point.
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