Digital Panoramic Photography


At the turn of the nineteenth century, an amazing photographic technique was developed for taking photographs in a complete circle. Using a rotating camera and long rolls of film, images were created that showed a scene that was impossible to capture with any lens on any conventional camera. The popularity of these photos was great, and it lasted well into the 1940s. Visit any county museum in any part of the country and you re almost certain to see these photos ”rows of high school students standing in front of the camera or soldiers in uniform at attention on the parade grounds. And, bulky as these cameras were, panoramic photography was used to record historic events (see Figure 14.12) as well as high school graduating classes.

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Figure 14.12: A panoramic photo taken during the San Francisco earthquake and fire, April 18, 1906. This image was made with a rotating Kodak Cirkut camera; the film was 10 inches tall by more than 40 inches long.

Panoramic photography faded (if you ll excuse the expression) into the realm of collectors and photo historians as we entered the era of 35mm photography and the explosion of consumer cameras that brought quality photography to the masses. The panoramic cameras still exist, but most of them are inoperable. It is a bygone era.

In 1995, Apple Computer reintroduced panoramic photography to the world with clever new software that can stitch a series of still photographs together to make a complete panoramic image that looks like those made with rotating cameras a century ago. QuickTime Virtual Reality puts the viewer in the center of a scene that surrounds them. Today several computer applications on the market will produce panoramic photos from a series of overlapping individual images (see Figure 14.13).

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Figure 14.13: A modern panoramic photo, taken with a Nikon professional digital camera as 12 vertical frames on a special camera bracket , then stitched with Apple QuickTime VR Authoring Studio.
New  

Photoshop CS has the ability to stitch a series of images together with its new Photomerge tool (File Automate Photomerge). With this tool, derived from the panoramic stitching tool in Adobe Photoshop Elements, you can blend multiple images together with reasonable success. The Photomerge tool works best with files in the 1 “5 MB range; large images (I tested it with a series of 34 MB files) are much harder for the program to digest, but do create acceptable images.

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A set of panoramic images for the following Photomerge practice is supplied on the companion CD. Named Merced1.jpg through Merced4.jpg , they provide an opportunity to test this new feature of the application.

To build a panoramic image from a series of individual digital images, follow these steps:

  1. Begin with the Photomerge control (see Figure 14.14). A browse dialog opens, enabling you to select images from existing files or a folder of files.

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    Figure 14.14: The Photomerge command calls up a dialog box where you identify the pieces of the panorama, in the order they need to be included.

  2. Select the images you want to compose into a panorama (see Figure 14.15). If you check Attempt To Automatically Arrange Source Images, the Photomerge tool will attempt to stitch them together, so you must load them in order. If you want to position them manually, uncheck that box, and it will free you to be at the controls. Click OK.

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    Figure 14.15: The contributing images of a merged panoramic image. Each has an overlap of about 20 percent.

  3. If you unchecked the Attempt To feature, a palette opens that enables you to drag images, optionally rotate them, and then stitch the panorama into a single image (see Figure 14.16).

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    Figure 14.16: The Photomerge control palette, showing the overlaps in images it stitches together. demarcation Notice the visible between the frame edges, each of which need to be retouched.

  4. Photomerge will stitch images together by a combination of reverse-distortion and blending techniques. When it is finished, you have an image that will require considerable retouching and correction in Photoshop. Notice the gaps in the sky, and subtle discoloration between the frames. When Photomerge is finished, it delivers its composite image in a new window in Photoshop (see Figure 14.17).

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Figure 14.17: The final file, after retouching, is quite handsome and represents the combined image area of four frames.

Compared to dedicated stitching programs such as Apple s QuickTime VR Authoring Studio, Photomerge does not blend the image intersections perfectly . In each attempt, I was left with visible errors between the images. These were easy to repair with the Rubber Stamp tool, but still required much work to make a satisfactory finished image. Photomerge is a good tool, but not a great tool, for putting multiple images together.

Some photographers prefer to stitch images manually by using the Layers functions in Photoshop and then selectively erasing parts of the overlapping images. This works fairly well when you are stitching several images that were made with a moderately long focal length lens. Wide-angle lenses exhibit too much distortion, which stitching programs remove by adding barrel distortion to compensate and make the adjacent images fit.




Photoshop CS Savvy
Photoshop CS Savvy
ISBN: 078214280X
EAN: 2147483647
Year: 2004
Pages: 355

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