![]() ![]() Taking a digital panorama involves systematically rotating your camera in increments to encompass the desired field of view. STAGE 1: DIGITAL CAMERA SETUP & PANORAMA ACQUISITION The trick is to hold the camera directly above one of your feet, then rotate your body about the ball of that foot while keeping the camera at the same height and distance from your body. With care, parallax error can be made undetectable in handheld panoramas which do not have foreground subject matter. Multi-row or spherical panoramas may also require a tripod-mounted panoramic head that keeps the lens at the center of rotation for up and down rotations. Panoramic photos of building interiors almost always require a panoramic head, while skyline vistas usually never do. This is apparent because for the image on the right, the light rays from both pillars still coincide, and the rear column remains behind the front column. SCENARIO #2, PANORAMIC HEAD: Here we see that the perspective is maintained because the lens is correctly rotated about its optical center. This makes it absolutely essential that the camera is rotated precisely about its optical center, and usually necessitates the use of a special panoramic head (as shown in the final scenario). SCENARIO #2: Here we see that the degree of misalignment is much greater when foreground objects are present in more than one photo of the panorama. Although some degree of misalignment may occur from this, the problem is far less pronounced as when there are close foreground objects, as illustrated for scenario #2. SCENARIO #1: The problem with the second image (right) is that each photo in the panorama will no longer see the same image perspective. Note: incorrect rotation assumes that the camera is rotated about the front of the lens correct rotation assumes rotation about the optical center Move your mouse over the three buttons below to see the effect of each scenario: The photo angle shown on the left (below) is the initial position before camera rotation, whereas the angle shown on the right is after camera rotation.įor incorrect rotation, the change in perspective that results is due to parallax error, because the camera was not rotated about its optical center. The two pink pillars below represent the background and foreground subjects. To see why foreground subject matter is so important, this can be illustrated by looking at what happens for two adjacent, overlapping photos which comprise a panorama. With scenario 1, small movements deviating from the lens's optical center have a negligible impact on the final image-allowing these photos to be taken handheld. Scenario 2 is far more sensitive to parallax error due to foreground subject matter. The location which we refer to is therefore the point at the center of the entrance pupil, which may also be called the "no parallax point" or "perspective point." A more accurate term is the entrance pupil, but even this refers to a small area and not an individual point. Note: The optical center of a lens is often referred to as its nodal point, although this term is not strictly correct. A panoramic head is a special device that ensures your camera and lens rotate about their optical center. If the camera does not rotate about its optical center, its images may become impossible to align perfectly these misalignments are called parallax error. Panoramas require that the camera rotates about the optical center of its lens, thereby maintaining the same point of perspective for all photographs. Tripod-mounted photographs with foreground subject matter in multiple frames. Here we identify two typical stitching scenarios, based on required equipment: Being able to identify when you need additional equipment can save time and money. The size and cost of panoramic equipment can vary drastically, depending on the intended use. BACKGROUND: PARALLAX ERROR & USING A PANORAMIC HEAD These stages will show that panoramas are not always straightforward, and require many interpretive decisions to be made along the way. The rest of this tutorial takes an in-depth look at stage 1, with details on stages 2-6 being presented in the second part of the tutorial. Note how stages 2-6 are all conducted on the computer using a panorama software package, after the photos have been taken. ![]() Selection of perspective and projection typeĬomputer shifts, rotates and distorts photos to conform with requirements of stages 2 and 3 Selection of desired photo alignment and input of camera and lens specifications ![]() Equipment setup and acquisition of photographs ![]()
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