How to Find Nodal Points for Panoramas
A few years ago I recorded a YouTube video on how to create detailed panoramas that you could print at 30 or more feet wide. That video on YouTube now has nearly 70,000 views and many comments. Now, for the prequel!
In the video I mention the term “nodal point.” Three of the most frequently asked questions from viewers have been, “What is a nodal point, why is it so important for panos, and how do you determine it?” I have just released a second video that gives step-by-step instructions on how to determine the nodal point of your lenses, so I thought this would be a good time and place to explain myself.
Panos or Panos?
For most people my two videos are superfluous, a prime example of overkill. Most photographers today can capture a decent panorama image with their smart phones in one tiny, hand-held sweep. Of course those panos cannot be enlarged very much, but they are terrific for Internet use.
Alternately, even photographers with DSLRs can capture a decent pano hand-held or on a tripod, using Lightroom, PTGUI or one of several other brilliantly engineered panorama stitching software programs. These panos will look pretty darned good and can be enlarged to a degree, although any imperfections in the pano will be magnified upon enlargement.
My two videos are geared to those advanced amateurs and professionals who need exacting panoramas that they may want to sell. These panos can be 10-, 20- even 50-feet wide. They will be showcased in upscale homes, office buildings, hospitals, airports or wherever a spectacular image needs to be displayed. In these cases, customers want highly detailed images that are sharp and don’t show pixelation. Enter the professional panorama where nodal points matter.
Nodal Points
The nodal point is sometimes referred to, and often confused with, “entry pupil” or “no parallax point.” In fact, these three are technically separate terms, but I am not going to go into an ;l exercise in physical optics. In the simplest terms, just consider this the point where the light rays enter the lens, are refracted and cross over each other.
The key take-away for you as a photographer is that you need to position that spot of your lens over the center of the tripod.
The intent of my video is to show you how to determine where that spot is. Once you determine that spot for each of your lenses, you are set to capture the best panos you have ever shot. Keep in mind that if you shoot your panos with a zoom lens, you will need to determine the nodal point/entry pupil at several different focal lengths. For example, with my 70-200 mm lens I determined the points at 70, 105, 135 and 200. I also record them in my iPhone so I have it handy while in the field.
So, with that as background, please go to my video and find out how to determine your nodal/entry pupil points. If you want exacting panos, you’ll be glad you did.