Panoramic Photography
Individual, but overlapping pictures are captured around a point of rotation. Image courtesy of Apple.
Click to see how dramatic 360-degree panoramas can be.
The three images above have been stitched
together into a single panorama (above right)
If your camera has a hot shoe, a bubble
level can ensure it's absolutely level when you take panoramic images.
Stitch Assist mode icon.
If you are a perfectionist, you can use two pan/tilt heads mounted together. You adjust the lower head to provide a level surface, and the upper head to rotate the camera. Image courtesy of Apple.
The Kaidan KiWi- LT is designed for aligning digital cameras capturing panoramas.
Courtesy of Kaidan.
Panoramas can also be vertical. You just shoot images one above the other.
There are lenses such as the 360 One VR that use a spherical mirror to capture a panorama in a single shot. Software then adjusts the distorted image to make it more realistic. Courtesy of Kaidan.
Most photographs, even those taken with a wide-angle lens, show just a sliver of the overall scene. To capture a more expansive view you have to spin around in all or part of a 360-degree circle, photographing from a single point in space out to the surrounding environment. There are some cameras
that will do just that—capturing panoramic images as they rotate. However most digital panoramas are created using an old technique. For years scenes have been photographed in sections so the images can then be mounted side by side to create a panoramic view. It has been the development of digital cameras and computer software that has made seamless panoramas possible. You capture a series of images around a single point of rotation, and then stitch them together with software.
Panoramic photos are much longer in one direction than in the other and can convey a sweeping image of a scene up to 360-degrees around. Using a digital camera there are three ways to achieve this.
- Some inexpensive cameras just capture a band across the middle of the image sensor, leaving unexposed bands at the top and bottom of the image area. You can achieve the same effect with any image you've taken by using a photo-editing program to crop it.
- You can use any camera to take a series of overlapping images as you pan the camera, and then use panoramic stitching software to assemble the frames into a seamless panoramic image. Since alignment is so important some cameras have a panoramic or stitch-assist mode that displays guide lines or part of the previous image in the series so you can accurately align and overlap the next photo.
- A few cameras make it possible to stitch the images together in the camera and automatically ensure that exposure is the same from frame to frame so the images blend perfectly. These cameras may reduce image sizes to keep the file small enough to manipulate it in the camera.
Generally there are three panoramic sequences from which to choose.
These photos show how an HP camera guides
you when aligning photos for a panorama that is then stitched together in the camera. Courtesy of HP at www.hpshopping.com.
Panoramic Equipment
It's certainly possible to do great panoramas without a tripod. However, if you get really serious, or you want to take 360 degree panoramas you should consider a tripod and a tripod head designed for the task. These panoramic heads serve a number of functions:
- They mount the camera so it rotates around the nodal point — the optical center of the lens. This isn't necessary for simple panoramas, but for extreme accuracy, especially for 360-degree views, the camera should rotate around the point in the lens where the light rays converge and cross over. Rotating around this point eliminates parallax errors that make it difficult for the software to accurately match images.
- They have built-in levels that help you level the camera.
- They have index, or degree, marks so you can rotate the camera just the right amount between shots. Some even have detents every few degrees so the camera snaps into place at the exact position.
Displaying Panoramas
After you shoot a series of digital images for a panorama, you use panoramic stitching software to stitch the digital images together into a seamless view. Once stitched you can output the panorama in a variety of formats.
- Printing. You can output the finished panorama as a still image in any of the popular file formats such as JPEG. Panoramas present a problem when printing because of their length. However, many inkjet printers are designed to print long images, some even supporting roll paper. If you want someone else to make the print for you, check out on-line printing services or look for a service bureau or graphics arts center near you.
- Web Display. You can put a panoramic photo on the Web just like any other still image, but you can also do it in such a way that anyone with a browser can pan and zoom it. To make this interactivity possible you have to save it in a format such as QuickTime VR (QTVR) and a viewer must have a browser or plug-in that supports that format. When these requirements are met a visitor can pan to look at the ceiling, down to look at the floor, or spin around the room. They can even click hot spots to move from one room into the next or to play other types of media, such as graphics, text, videos, or sounds. Some applications let you save your panorama in an HTML format so the panorama's page and all other necessary files are generated automatically. You don't need any special HTML or Java programming knowledge, just upload all of the output files to your Web site.
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