VFX I

43.4 No-Parallax Point


What is the No-Parallax Point?

Rotating the camera on the No-Parallax Point (also referred to as Nodal Point) results in no parallax between foreground and background. To avoid errors in the panorama stitching process we need parallax-free images, which we’ll only get when rotating on the No-Parallax Point

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The exact location of the No-Parallax Point varies from lens to lens

For our Canon EF 8-15mm fisheye, the No-Parallax Point is close to the entry point of the lens, approximately at the first black ring


Finding the No-Parallax Point

The concept

Align viewfinder’s center with tripod’s center of rotation

Align No-Parallax Point of lens with tripod’s center of rotation

The way to adjust the axes will vary for each panorama head model


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Enable viewfinder’s center

Enable the Grid Display for the viewfinder

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Align with the tripod’s center

Point the camera downwards and adjust the 2 axis on the panorama head, so that the viewfinder’s center cross matches the tripod’s center of rotation

Rotate around the center and check the entire 360˚

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Find 2 vertical lines

Level the camera. Find 2 vertical lines, one very close, one further away. You can use tripods, lamp poles, door frames, window blinds etc.

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Camera centering overlapping lines

Position camera that the 2 lines are in the image center and overlapping perfectly

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Rotate and monitor shift

Pan to the side and monitor if the 2 lines are shifting towards the edge of the frame. Rotate in both directions

The lines in the example have shifted slightly: There’s parallax and we’re not on the No-Parallax Point yet

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Adjust millimeter by millimeter

Adjust camera position to align No-Parallax Point to tripod’s center. For Nodal Ninja: That’s the lens-ring connecting to the head

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Adjust, rotate and monitor until no shift

If the lines are still drifting apart, return to adjusting millimeter by millimeter and repeat till they’re not shifting anymore

You have found the No-Parallax Point when both lines are overlapping perfectly while rotating in both directions

If the lines are not shifting: Congrats, ready to shoot