Panoramic Photography With Your Digital Camera; Gear And A Guide To Maximum Panoramic Power Page 2

Critical Setup Steps
The setup stage is critical. The first step in the setup is to level the tripod. Next, mount a rotating head on the tripod and be sure the head is also level with the tripod.

Now let's deal with the camera. It is very important to be sure that the optical node of the camera lens is your pivot point. OK, before you decide to abandon this article because this sounds complicated, let me walk you through what really is a simple process to handle this requirement. Believe me, it's worth the little bit of time.

How do you find the nodal point in today's complicated, multi-element lenses? Basically, these lenses function amazingly like their simple one- or two-lens ancestors of a few years back. The common but incorrect pivot point photographers sometimes select when they use a tripod is the camera mounting point. The correct way to find the nodal point is to determine the focal length of your lens. If you're using a fixed focal length lens, it's simply the focal length of the lens. If you're using a zoom lens, it's the focal length reading when you've finished framing your composition. Then, find the mark on the camera that indicates the location of the image collector plane. (For years this was called the film or focal plane). You measure forward from that mark a distance equal to your current lens focal length to locate the optical node of the lens, and then take note of the location on the lens. You want this point, the node, directly over the pivot of the tripod so the camera swings around the nodal point as you pan to capture your image. You will need to carry a small millimeter ruler with you to do the measuring (my compass, which I always carry when shooting, has a rule in both inches and millimeters).

This photo is an exploded view of an inset portion of the Margerie Glacier to illustrate the quality one can obtain when printing the photo in a larger format.
© 2004, Jim Porter & New Century Images, All Rights Reserved

If you make frequent use of zoom lenses, be aware that the nodal point moves as you move the focal length ("zoom" the lens) in and out to frame your scene. And since you are rotating the camera-lens combination around the optical nodal point to capture a panorama, you need to re-establish the new optical node carefully when you change the zoom. You must remember to relocate the new nodal point over the pivot each time you change the zoom.

Now, how do you mount the camera if the node is not at the mounting point on the camera bottom? (By the way, it's unlikely to ever be at that location.) You do this with the slide mounting plate that I referred to earlier in this article as one of the few pieces of equipment that you need to add to your gear. My practice is to carry a macro mounting slide that does double-duty for both panoramic and macro shots.

A useful way to check to see that everything is ready to start shooting is to align a nearby object with a distant object and then to watch the alignment through the eyepiece as you pan the camera through your scene. If the two retain their relative position as you pan, you've properly positioned the nodal point. If the two objects move relative to each other, move the camera forward or backward slightly until you observe no relative motion as you pan. This serves as a good final check that you have the nodal point over the pivot point of the panning head.

Capturing The Images
There is very little more to do now before shooting. Decide on your exposure, set the camera to Manual so it will remain constant, set your aperture and shutter speed for that exposure and begin. Be sure you cover the scene adequately with enough overlap of each image. I have found that the process works best with nothing less than a 20 percent overlap, and I use an overlap closer to 30 percent. A tripod panning head with a scale in degrees can be very helpful to make your overlaps more precise.

Putting It Together
Now that you have your shots, it's time to create your panoramas. If you are a Photoshop user with the latest CS version, and if you have done a decent job of capturing the images, the final step is simple. Simply select the images you want to stitch together while still in the File Browser and click on Automate/Photomerge. Then sit back and watch the screen flash as Photoshop assembles your panorama--it's almost magic. If you have Photoshop software but not the CS version, my advice is to bite the bullet and get the upgrade. If the upgrade seems expensive, consider that it's a lot cheaper than buying a panoramic camera and some of the high-end equipment that give panoramas a polished look. If you're comfortable using Photoshop layers, the CS version might not be that important. But for those who are less familiar with Photoshop, the CS version is worth the price for the features it gives you.

I encourage you to give digital panoramas a try. There is no need to be intimidated or to suspect that you can't do it, especially if you have either good stitching software or Photoshop CS. The results of panoramic photography can be stunning, and you'll be surprised and pleased by how quickly you can master the technique.

ARTICLE CONTENTS

COMMENTS
staufr's picture

One question - Should I use the effective focal length on a DSLR or the reading from the lens? I use a Canon EFS 18-55 currently (new camera). It has a 1.6 multiplier for its sensor size.

Ron

X