Panorama photography is a method of increasing the field of view over and above the capabilities of a wide angle lens and, therefore, increasing the aspect ratio of the finished product.
The purpose of the panorama is to better express the sense of space and the expansiveness in any given scene we wish to photograph. A panorama more closely represents how we view the world and communicates the physical world with detail and authenticity.
Panoramas Made Simple: The Basics of Taking a Panoramic Photo
Ok, we are going to go into a lot of detail about taking the perfect panorama, but here's all you need to know about how to take a perfect panorama photo.
Keep the Camera Level
This is essential to taking a good panorama. Keeping the camera level ensures the vertical and horizontal alignment of all objects is maintained. If you use a tripod ballhead (and most tripod users do!) that means you will need to level in two SEPERATE places: the tripod clamp and the tripod legs. Leveling the tripod legs ensure your ballhead panning base is completely level as you pan the camera for the different panorama shots. Levelling the tripod clamp endures the camera itself stays parallel to the panning axis (of your tripod panning base) as you pan.
Simply slapping on a spirit level on top of your camera and levelling it WILL only ensure the camera / tripod clamp is level to the tripod panning base. You will also need to level the tripod legs.
The easy solution to avoid having to level both the tripod clamp and tripod legs is to use the Really Right Stuff PCL-1 Panning clamp. You simply adjust for level using the build in panning-clamp level, and your entire setup is level.
Parallax can ruin your panorama image. This has to do with the positioning of your optical center of the lends over the point of rotation. You can eliminate Parallax with a nodal slide.
Parallax is big issue when it comes to Panorama photography. It’s essential that you find the No-Parallax Point to eliminate or reduce Parallax.
NPP (No-Parallax Point)
Whilst it is the photographer her/himself who objectifies, a camera or the basic biology of the human eye can only subjectify. Everything presented to us in the 'scene' (in this case a landscape), sits entirely in relation to our subjective viewpoint. Stand, for example, in your garden and take a step left, right, forwards or back and you will see foreground and background objects shift in relation to both yourself and each other. A piece of wall hidden behind a leaf can, for instance, suddenly become apparent or what you can see reflected in a puddle will change. The same holds true for how a camera sees.
This 'parallax' is most evident when you hold a finger up at arm’s length. If you look through and beyond the finger, first with one eye and then with both, you will see that distant objects obscured by your finger will change. This is because the parallax has changed as the steropsis of the eyes kicks in and out. It is also the reason why passengers in a car sometimes think you are speeding: how they see the numbers on the speedometer in relation to the needle is different from the point of view of the driver.
However, if we can fix this point on the camera; create a No-Parallax Point, in three dimensional space then little or no shifting in the relationship of distant objects will occur when the camera moves to take the different composite images of the panorama. Without fixing this point there will often be a 'ghosting' or 'tracing' within the final image. Here is an example of a panorama taken without using a fixed No Parallax Point
image image image
Although some software (particularly Autostitch) can compensate for this effect, there is never any guarantee that you will not be left with mismatched elements and aberrations that can ruin the final panorama. So where exactly is the No Parallax Point on your camera?
Unfortunately the NPP it is not quite on the axis that the tripod rotates upon but is further forward than this: the iris or entrance pupil. On most DSLR's this would be located away from the sensor towards the centre of the lens barrel. This NPP or Nodal Point is visible if you open the aperture to around f6.3 and, with the back of the camera facing a light source such as a window, look in through the front of the lens whilst holding the depth of field preview button. Just forward of the white dot you'll see is the No Parallax Point.
In order to save any frustration later, this is the point that needs to be fixed in 3 dimensional space and the point around which the camera should revolve. In most cases, and for distant landscapes taken across the horizontal axis, the tripod head is a sufficient point on which to rotate the camera. The need to control the NPP becomes more critical when either:
a. intend to stitch both horizontally AND vertically, or
b. when close foreground objects are involved.
Of course all of this assumes that the camera's orientation is landscape, but for greater detail and image height the best results are achieved by flipping the camera to a portrait orientation. However, using this method means there is a small problem to overcome. Not only will flipping the camera's orientation on a traditional tripod head mean that the tripod's balance is off-center, but the camera now also swings in a more dramatic arc around the tripod head, meaning that for the vast majority of composite panoramas, the NPP will shift to an unworkable level.
If this is all mumbo jumbo to you still, then here's a simple breakdown of the Parallax problem. Image parallax occurs when both near and far objects don't match up when you overlap the images. So if you are shooting a landscape scene with a fence with multiple shots, the same fence post in the first image you take must align exactly with the same fence post in the second image.
This parallax effect can be eliminated if you place the optical center of the lens on the camera right over the point of your rotation. However, if you look at most camera setups, you'll notice a problem here. If you place your camera on the tripod, the lens sticks out -- thus you cannot position the optical center of the lens over the point of rotation (the center of the tripod).
There is a simple piece of equipment to help deal with this issue: a nodal slider. This is basically a rectangular piece that you attach your camera to one of the end points. The slider connects your tripod to your camera and allows you to slide the camera back, allowing you to reposition it so that the optical center sites over the point of rotation -- i.e. the NPP.