Sanderson Photo Art

Images and photography blog of Peter Sanderson

Panoramic Photography

Panoramic photography is a technique of photography using specialized equipment or software that captures images with horizontally elongated fields of view. It is sometimes known as wide format photography.   My panoramic photographs are  constructed from a series of carefully captured digital images that then have been combined into one on a computer.

Meticulous attention to detail and the use of specialized equipment is used to ensure a technically correct panograph.  Each image must be taken with the same spatial alignment and exactly the same exposure, focal length and aperture.

I start by metering the entire scene to determine an average exposure setting then manually set the shutter speed and aperture. A tripod is set up with a panning head level with the horizon.  A series of overlapping images is then obtained.  It is important to rotate the camera about the nodal point of the lens which is well ahead of where cameras typically mount on a tripod. The nodal point is where all the incoming light rays through a lens converge on their way to the camera sensor.

When combining two images, the common elements must exhibit the same spatial relationships. If they do not (called parallax error) the resulting combined image will contain double images also known as ghosting.  Close one eye, hold a finger out in front of the open eye then turn your head.  If you rotate your head about the axis of your neck, you will see your finger seeming to move faster than distant objects. Your finger and distant objects are not spatially aligned. If you try to rotate your head at the axis of your eye, you will notice your finger maintains a constant spatial relationship to distant objects. When doing so you are rotating at the nodal point of your eyes.

lens nodal point

My camera mounted on the rear of a macro rail placing the lens nodal point at the rotation point of the panning head. Doing so allows the overlapping portions of adjacent images to have the same spatial relationships of near to far objects. This prevents ghosting of near objects when you stitch together the images.

Cameras tend to mount to tripods at a point on their body, usually several centimeters behind the nodal point.  I mount my camera to a macro focusing rail and panning head (I call this my “poor man’s panoramic head”) and then move the camera back on the rail so the rotation point is at the nodal point of the lens.

Once the overlapping images are captured, they are transferred to a computer and digitally stitched together using Photoshop. The result is a very high resolution image that can be printed to very large sizes.

stitching mcdill

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