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How to Find the Nodal Point
The simple steps outlined below are sufficient for finding the optical center (aka nodal point) for most shooting situations. But some shooting situations are more demanding, and may require a method that delivers a higher degree of precision. For example, nodal point positioning is absolutely critical anytime you're shooting a scene that has diverging/converging lines (roads, paths, fence lines, windows, etc), especially when these elements are in the foreground and close to the camera. In that case, skip to the bottom of this tutorial for further recommendations. Once you've found the nodal point for your lens, make a note of it so that you can easily repeat your setup the next time.
 Level Your Equipment
One Step Leveling
If you use our PCL-1 panning clamp, this step is a snap. Loosen the ball and shift the clamp until the spirit level indicates its level, and in one step, you've leveled both the camera (the lateral axis) and the panning base (the axis of rotation).
Two-Step Leveling
Alternatively, level your tripod and camera separately. When you level the tripod, what you're really trying to get level is the panning base of your ballhead. For leveling the tripod, a leveling base or a leveling center column makes the first step quick and easy. And to level the camera? Use the spirit level built into one of our clamps, or use a double-bubble level mounted in the camera's hot shoe.
 Place the Nodal Point Over the Axis of Rotation
Where is the Nodal Point? The physical location of the optical center is unique for each lens. For prime lenses, the nodal point (with focus at infinity) is stationary. For zoom lenses, however, the nodal point typically shifts for each focal length. The location of the nodal point is commonly expressed as its distance, in millimeters, forward of the film plane/digital sensor.
The nodal point is best determined by experimentation: Use a "nodal slide," such as our 7.4-inch long MPR-CL II. The objective is to slide the camera along its lateral axis until the nodal point is positioned over the axis of rotation. Precise positioning is critical if your subject matter is close, but much less important if you're shooting distant landscape shots.
- Find two vertical objects; one near, one far. Position your equipment so that these objects line up in the viewfinder.
- Level your equipment.
- Mount and center your camera on the MPR-CL II.
- Start out by positioning the approximate center of your lens over the axis of rotation.
- Now pan left.
- If the rear object appears to shift to the left, then you are ahead of the nodal point. Slide the MPR-CL II forward and try again.
- If the rear object appears to shift to the right, you are behind the nodal point. Slide the MPR-CL II back and try again.
- When the optical center of the lens is directly over the axis of rotation, the rear object will not appear to move relative to the front object.
- Record your results so that your setup can be re-created.
 What Image Settings Should I Use?
- Decide how much depth of field you want across the entire scene and choose an appropriate aperture. Since most panoramas are of places and not people, you can set maximum crispness and depth of field out to infinity by focusing on the hyperfocal distance.
- Set the camera's exposure mode to Manual; exposure across the scene needs to be consistent. If you're not comfortable with manual exposure settings, take a few shots in Aperture Priority at your chosen aperture, note the shutter speed, and use that setting for manual exposure.
- If you're shooting digital, don't use Auto White Balance. Set your White Balance manually.
- Decide how much overlap you need. A rule of thumb is 30-50%, but the actual amount of overlap is not that important and the amount of overlap can vary from image to image.
Need Higher Precision?
The key to high precision nodal point determination is to align multiple vertical objects that are fine and narrow. Also, the vertical objects that you choose must be perfectly vertical to ensure that the objects are perfectly parallel.The best tutorial that we've ever seen on this subject is available from Alain Hamblenne's web site. He calls his tutorial "The Grid" and his method involves hanging a fine mesh grid in his garden. Click HERE to download Alain's tutorial in PDF (link published here with permission).
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