Exit Pupil / Nodal Point Information

It has been said many times that DxO has extensive data / measurements of lenses, cameras and combinations thereof.

I would find it very useful if DxO could give us Nodal point info for aligning a lens with a specific (or general) location (relative to the image plane or lens) for panoramas, before taking the pano.

There are a few lists out there, but not really for modern mirrorless cameras and lenses. I do realize that figuring this out isn’t hard, just annoying to do, surely DxO has had to figure this out for their software.

They literally have this app that lets you fix perspective & parallax distortions :slight_smile:

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Hello there Adam and welcome.

That’s a quite nice idea.
You might want to post it in the feature request forum and vote for it.

I believe you can figure that out for your camera/lens yourself, the first nodal point. Though it would be handy if they are mentioned somewhere.
Off topic, but a question I have in my mind for a long time. It’s said that the image distance+subject distance=working distance. But both image distance and subject distance are measured from their respective nodal points. One can’t add them. Can you tell me if I’m right?

George

Most optical formulae come from an “infinitely thin” lens model. This means that these rules relate to the nodal point. NP can wander with focus distance and focal length settings, which makes it difficult to provide NP info in simple form.

Also, there’s no such thing as a 0-tolerance lens: Each lens is manufactured and the final product is within more or less tight tolerances. As Roger Cigalla from LensRentals pointed out several times (in fact, there are 17 pages with 5 articles each related to sample variations :flushed:), unless you’re not looking at a batch of, say, 10 copies of the same lens, you always have to face certain sample variations which also influence lens profiles

If figuring out isn’t hard, you should be able to do it yourself, right :wink: And what makes you believe, the nodal point of any lens is relevant for a lens profile? PL is not a panorama software, therefore the makers of pano-software might be a good address to ask for nodal points? I’m not asking because “I know they don’t measure a nodal point”, I just don’t know why this specific feature would be measured - and even if it would, you have to make your own experiments due to sample variation.

You might find something here:
https://www.photonstophotos.net/GeneralTopics/Lenses/OpticalBench/OpticalBench.htm

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