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I have the following two images, with a stick in the peak of a golf ball in one, and in the trough in another:

a a

They are very similar, however they are slightly misaligned due to nodal pans in between photos. We can safely assume that the size/position of the golf ball, focal length, Y/Z position, Y/Z tilt and zoom of the camera have all remained the same. All that has changed is that the camera may have moved ever so slightly forward or backwards, and panned at most 10deg from left to right, and that the stick has also possibly tilted on the X axis. Is there any way, using Photoshop, Lightroom and/or GIMP/Hugin to line up these images? As fairly evident by the subject of the photos, I am trying to measure the depth of the pit, but I first need to line up the images before I can make the calculations. I have been able to line them up after an hour of painstaking manual warping, but I am looking for an easier method that works automatically. I have found some tools (like Hugin on CMD) that work fairly well, but the rotation of the stick seems to throw it off. Are there any better tools/methods for doing this (I have 20+ sets of images that I can't spend a whole week lining up)?

Thanks.

  • 2
    vtc b/c "I am trying to measure the depth of the pit" -- OP is trying to use camera as measuring device, not for photography per se. – xiota Feb 6 at 23:21
  • @xiota However, the issue of setting up a camera system for no-parallax panorama is a fundamental technique for that type of photography. Change the end goal to "for the purposes of demonstrating how to setup a no-parallax panorama", without changing the camera, mounting equipment, or even test subjects, and there's no argument about its topicality. – scottbb Feb 7 at 13:52
  • @scottbb I don't understand what or how OP is trying to measure. But what if the panning is an intentional part of the process? For instance, one could measure distance using a stereoscopic image pair (as our brains do all the time). Avoiding parallax would make measurement impossible. – xiota Feb 7 at 21:43
  • What is this "depth of the pit" that you are trying to measure? – xiota Feb 7 at 21:47
  • I agree with the vote to close in this case. Methods commonly used to correct for misalignment are fine for photographic purposes but no good for the measuring-device purposes desired here. – mattdm Feb 8 at 13:40
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There is no way to line up the particular images you took/posted. But there is absolutely a way to setup your camera & tripod to so that you can take perfectly aligned images for panoramas.

What you are experiencing is known as parallax, and the technique involves finding the no-parallax point of the lens. At a minimum, you need a camera mount that can rotate, and a means to arbitrarily position a camera forward or aft on top of the rotation mount. A tripod with a pan feature, or ballhead with a pan axis, is enough for the mount. For the fore-aft slide, ideally you'd use a clamp mechanism, with the camera mounted on a rail that can be positioned forward/aft in the clamp.

The setup will look like this:

enter image description here
Setup for a single-row panorama shot. From ReallyRightStuff.com

A note on terminology:

The location of the no-parallax point is the center of the entrance pupil of the lens. Often the NPP is referred as the "nodal point", or in your case, there's a "nodal misalignment". This is not strictly correct; the nodal point(s) of a lens are not the same as the entrance pupil. Nevertheless, the misnomer terms persist (especially with the "Nodal Ninja" brand of panorama tools on the market.

The technique for finding the no-parallax point has been well-documented here, and at places on the web.

Great descriptions the technique(s) for finding the NPP:

Here's a handy cheatsheet for adjustments to make when finding the no-parallax point:

enter image description here
No Parallax Point: NPP Determination Procedure, by Henrik Fessler. CC BY-NC-SA 3.0

  • OP performed a panning movement, not rotation. It's impossible to avoid parallax when panning. Also, it's likely that panning is a necessary component of OP's measurement process. Note that OP has maintained similar framing between images. – xiota Feb 7 at 21:45
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    @xiota I'm not sure OP is fully sure about the total movement (OP mentions camera may have moved forward/backward, and maybe ~10° pan motion). However, your point in your comment to OP's question is 100% spot on: you can't both eliminate parallax, and use parallax as a tool to measure surface features and/or 3-dimensional depth. I read the question as OP trying to eliminate parallax, but I'm not so sure that's what they're really hoping to do. – scottbb Feb 8 at 19:41

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