panoramic photographs
Some camera or lens manufacturers provide details about the nodal points of their products, but on
the whole, this type of data is hard to fi nd and it is up to the shooter to determine the nodal point of
his/her own equipment. For this the main method is usually referred to as the ‘lamp post’ test and
is based on a two-step process. With the camera set up and levelled on a panoramic head use this
step-by-step guide to fi nd the nodal point.
Start by adjusting the camera from side to side until the centre of the lens is positioned directly
over the pivot point of the tripod. This is the easy part.
Next, you need to move the camera back and forwards whilst rotating the camera and
comparing the visual distance between foreground and background subjects. When the visual
distance is the same the lens nodal point is positioned over the pivot point of the tripod and
you are ready to start capturing the source photos for your panorama.Checking your results
If the lens’ nodal point is rotating over the tripod pivot point then the visual distance (gap) will
remain the same throughout the movement. If the distance changes then the lens is not positioned
correctly and needs to be moved either forward or backwards to compensate.
With a little trial and error you should be able to locate the exact nodal point for each of your
lenses, cameras and lens zoom points. VR tripod heads, like those made by Manfrotto, excel in
this area. The fi ne-tuning controls and set up scales enable the user to accurately locate and note
the position of the nodal points for a variety of lenses and/or cameras. With the tests complete the
results should be recorded and used whenever the same camera set up is required again.
1.
2.
Handy guide to nodal point corrections
Use these rules to help you correct nodal point errors:
Moving the lens backward, if rotating the camera away from the foreground object, increases
the visual gap, or
Moving the lens forward, if rotating the camera away from the foreground object, decreases
the visual gap.1.
2.
Camera assisted hand held
Unless you are a committed panoramic shooter you probably won’t have a specialized tripod
head handy the next time you want to capture a series of source images. This generally leads to a
situation where you attempt to photograph the pictures by simply spinning the camera in your hands.
Most stitching software will be able to blend pictures captured in this way but the inaccuracy of the
photography process does lead to more editing work back at the desktop. To improve the accuracy
of hand-held capture several of the bigger camera companies such as Nikon and Canon include a
special ‘panorama assist’ shooting mode in their mid to high range compact cameras. The mode
ghosts the previous shot in the LCD screen so that you can line up the next picture accurately.
This saves you from the expense of purchasing a professional panoramic tripod head whilst still
ensuring accurate overlap and positioning of the series of photos. As well as helping with correct
alignment and positioning these special shooting modes also lock in focus, aperture, contrast and
white balance at the beginning of the shooting sequence aiding consistency.