The Trinity River Vision at 360Texas.com website

 12January 2005 0945am Canon 20d, Canon 28-135 IS UL @ fl 28mm, ISO 200 1/160sec f/8.
 8 portrait images RAW format 2336 h x 3504 w 7.8mb converted to BMP format each  23.4mb 
 30% image overlap completed panorama 3247 h x 9764  w pixels bmp format 108.9mb
 Resized to the image above 147 h x 521 w pixels  72ppi and 60kb

Entrance Pupil | Nodal Point | Exit Pupil
Panorama Imaging
Photographs and Panoramas are designed to stimulate and motivate you. 

Definition Webster's New World Dictionary defines Panorama:
as a word coined in 1789 by Robert Baker (1739 - 1806) as:

1a) picture or series of pictures of a landscape, historical event presented on a
continuous surface encircling the spectator, cyclorama,  b) a picture unrolled before the spectator in such a way as to give the impression of a continuous view 2) an unlimited view in all directions
3) a comprehensive survey of a subject
4) a continuous series of scenes of events; constantly changing scene.

Here is my first attempt at creating a panorama.  Notice the images are similarly exposed and somewhat vertically aligned.  However, it seems I tilted the camera down the farther I went along to the right. This created a stair step affect.  Matching up the images took its toll ... I think I ran out of cellophane tape.  This panorama is a series landscape images taken with our Nikkormat with a Nikkor 50mm lens.  I took this image with a Nikon 990 digital camera.

Ok so where to begin?

What kind of camera and equipment is needed? Any type really, however for this discussion we will be using a digital camera with 35mm equivalent to 24mm or wider lens. Wider lens provide more angle of view and fewer images are required to make a full 360 degree image.  A partial panorama may also be your end product.  A sturdy tripod and bidirectional bubble or spirit level are helpful for leveling the top of camera.

What kind of software is needed to make a panorama? Some digital cameras come bundled with panorama software.  Adobe Photoshop 7 and CS use Photo-merge.  Easypano Panoweaver and iSeemedia PhotoVista are two easy to use stand alone software packages.

Here is some background for general understanding.    It is not necessary to know the detail, just be aware of the concepts.

Objective: First came the world and it is a round sphere.  Your 8 to 24mm lens creates distorted lines that will need to be software adjusted to become straight again.

We will assemble an equi-rectangular image from a series images that will eventually be a cylinder or spherical display. A cylinder is analogous the label on vegetable tin can. A sphere would like your image projected on the "Inside" of a basketball.  So lets start with a FLAT cylinder world picture like shown below.

Cartographers (map makers) use an Equi-rectangular Map Projection.  A projection which maps a sphere (or spheroid) onto to a plane.  Simply put, the World is a Sphere shaped object.  A flat world map is displayed as a two dimensional digital picture.  This type of projection has a aspect ratio of 2 wide : 1 high or 2:1 ratio.  Your finished multi framed stitched image composite will look something like this:

When we are finished with our panorama we will use our normal rectangular flat stitched cylinder image printed on a photo paper or to be view as a sphere.

For example this is a stitched cylindrical image suitable for printing (without the grid):

Using this cylindrical image we might also display it like this:

This is a web browser java viewer. Works best with MS IE 6 and MS Java Engine

So now we know what the printed cylinder or web based sphere view should look like.  Lets try and create a sphere or cylinder (most common) type panorama.

Creating a panorama is a simple task that requires a bit of technical understanding for it to produce a better than average final photographic panorama for use on the internet.

Hardware: A camera with a suitable wide angle lens, sturdy tripod, and panorama head.  I made three home made panorama heads before earning enough money to purchase a commercial head. One of these panorama heads we used on our first commercial photo shoot with great success.  It was a simple aluminum L shaped bracket that fastened to the top of the tripod. However, a commercial pan head allows for alignment flexibility.

The purpose of the L shaped pan head is to align the center line of the lens (left and right) over the top of the tripod point of rotation to remove parallax.

Locating the lens principal point (sometimes called the nodal point) assures that each of your images are taken at the distance from the same object. We found that the manufacturers sometimes makes a distinctive ring mark for this location. This point is the aluminum colored f-stop index ring.  However, it is always best to refine this location by performing a simple Test shown below.

As shown in the left picture it is best to set the lens ring up over the top of the point of rotation.  Then rotate the camera left and right until the near and far objects do not move from their positions.

Principal (Nodal) point Test (shown using a Nikon 990 and FC-E8 8mm fisheye lens)

There are many types of camera lenses to include Prime (no zoom),  Zoom lenses (several focal lengths), Lens Adapters.

Prime Lens

The point of image inversion must be directly above the tripod point of rotation. It is called the Principal or Nodal Point

 

Prime Lens

Prime lenses do not have zoom ability. 

Nikkor lenses usually have a gold /silver ring near the Aperture Ring (F-Stop mechanism) that marks the location of the internal iris diaphragm. This should be your starting location when performing this test. 

If your lens is marked 50mm focal length, then you can confirm the iris diaphragm position by measuring 50mm from the film/ ccd/ cmos plane out along the lens axis and lens barrel for the point of tripod rotation.

Start testing from this gold or silver ring on the lens.

Set the camera and tripod 3" from front of table edge and about 4" above top of front batteries. For a dSLR camera place it far enough back to be able to see the  2 batteries are shown in the picture, 1 in front and 1 in back  Point the camera straight ahead.  Move batteries around to the back battery bottom is directly over top of center of front battery.

Left view - take picture. Right View - take picture.

View both left and right pictures in Photoshop.. zoomed in.  If in the left and right view the batteries change position ... then you have not found the nodal point.

Correct Nodal point.. the batteries will not move at the red dots should line up directly over the top of each other.

In this picture.. the BACK left and right battery red dots are on the OUTSIDE of the bottom battery red dots.  This indicates I need to move the camera back 1 or 2 millimeters and retest.

This type of test will work with most lens types.

For those folks that use a 183° fisheye lens when viewing your completed panorama will have a perfect circle of your panorama head.  For those using a wide angle lens you will not have enough vertical field of view to see the tripod head.

Click here to see NP for Canon and Sigma 8mm lenses.

950 and FC-E8 fisheye   990 WC-E63 and Kaidan 990 Head 
(Courtesy Bruce Anderson, iSeemedia, Tokyo Branch Office in Japan)

Nikon 995 Fisheye and WC-E63 and *note for FC-E8
Dimensions courtesy of Fabio in Belgium

Note for WC-E63 use 22 (not 29) mm distance to NP^                      *between FE2 and FE1 position 5mm

Click here for Lens Specification's Chart 
Click here to see how to align your TRIPOD HEAD
Richard reveals what is INSIDE the Nikon 950