Panoramas Explained

Here a tutorial showing how to make panoramic pictures with an Olympus E-10 and a Raynox Fisheye lens.

1. Capturing The Scene

2 rows of 6 pictures are taken with the fisheye lens, one at -30 degrees, one at + 30 degrees
2 pictures are taken at about 60 degrees angle to cover the top (due to the size of the fisheye lens I cannot rotate the camera up until 90 degrees, or the camera body would bump into the panoramic head)
1 picture of the tripod is taken
1 hand held picture without the tripod is taken
Each source picture has a resolution of 1680x2240 pixels

This scene was taken at constant exposure with a shutter speed of 1.3s and an aperture of f9.

2. Rectilinearizing Pictures

Pictures above show heavy distortion due to the fisheye lens. After using the Pano Tools Remap plugin in Photoshop, pictures look like this:

3. Preparing The Bottom Picture

On the bottom picture, the tripod is clearly visible:

In Photoshop, part of the other picture without the tripod is rotated, rescaled and extracted:

Then combined:

This step ensures that the bottom picture borders (in this case, the chairs) will match and overlap the other pictures correctly, since it was taken with the tripod. If the whole handheld taken picture was used as is, it would not be aligned with the other pictures that well, creating artifacts. In the combined picture above, the arm of the panoramic head can still be seen, but there is enough overlap with the other pictures so that we can remove it from the final panorama.

4. Stitching

Images are stitched together, one at a time, using RealViz Stitcher.

5. Removing Artifacts

The bottom part of the panorama still has visible tripod parts. They can be removed with the artifact removal tool (gray areas):

Because images overlap, some artifacts visible on one picture but not the other (as is the case for the tripod) can be removed. I also accidentally moved the chair on the bottom left corner of the image above. I was able to remove most of the artifacts with the software.

Other areas of the panorama can be fine tuned to remove bluriness.

6. Previewing The Panorama

The virtual camera is positioned so it looks at a level angle and a preview is rendered.

7. Rendering The Panorama

The panorama is rendered as a TIFF file in 5120x2560 resolution. I found out this resolution allowed pretty good full screen panorama viewing with FSP Viewer and still keeping a good amount of detail. And also, it is a four times the horizontal width of my flat panel monitor. Such a resolution enables printing in 12" x 18" at 280 dpi. Not too bad. Twice this resolution can be obtained by not using a fisheye lens and recording 50 images instead of 16. The relatively short picture taking time (about 5 to 10 minutes) makes the fisheye lens a good compromise.

I then view the file thoroughly to scan for artifacts. Some of these can be removed in PhotoShop.

Other artifacts can be removed by going back to the stitcher, defining artifact polygons, and rendering again. Usually, most of the artifacts / bluriness appear in the top / bottom areas of the panorama. This is where images have the most overlap and also because of the spherical projection, defects are amplified in these regions.

8. Preparing for Web Viewing

Smaller versions of the panoramas are generated:

one in 1280x640 for the java viewer. Netscape and other browsers have limitations on memory size for Java programs. This is why I keep web viewable panoramas to a reasonable size.
one in 480x240 makes a good thumbnail for my "Panorama Corner" page