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I took a few images of sunset with a tripod (each shot with -3EV and +3EV). I'm working with Hugin. Setting control points I have done manually. Since I'm encountering heavily ghosting issues I simplified my setup:

I took two images A and B (both 0EV) and stitched them with option "Exposure corrected, low dynamic range". The result is fine. There is no ghosting or other issues.

Then I tried to take one additional image A' of the sun (-3EV) and put it to the same stack as A. For image A' I also set control points between A and A'. The alignment seems to be fine.

A and B and A# with -3EV for sun.

Between A and B there is now partially a ghosting. When stitching I tried "Exposure fused from stacks" as well as "Exposure fused from any arragement" and "High dynamic range". The ghosting is always there.

Ghosting.

Next I tried to set a mask on the A' (-3EV) image with option "include region from stack" to have a just a better exposure of the sun. But it does not solve the problem of the blending to B.

Note: The ghosting happens on mountains in the distance.

Second note: Since stitching of A and B with option "Exposure corrected, low dynamic range" is working fine I assume there is no parallax problem.

Any idea what is causing the ghosting?

I could also provide a sample project.

Edit: Single images:

A enter image description here

A' (-3EV) enter image description here

B enter image description here

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  • Can you post the original files, perhaps shrunk down a bit so they don't take up a lot of space. Label them according to your discussion.
    – qrk
    Apr 2 at 23:24
  • @qrk Images added.
    – xforfun
    Apr 3 at 18:00

2 Answers 2

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The ghosting is probably coming from moving the camera in space between shots, particularly if you were handholding and not using a tripod with a calibrated panohead to rotate around the lens's no-parallax point.

You may need to do masks/layers correction to eliminate the ghosting.

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I'm unable to create a reasonable pano from your A & B source files. A few things are obvious:

  • The nodal point is off as evidenced by the plants in the foreground and the railing. It looks like a lateral translation between images.
  • The clouds are moving between the shots which will cause blending issues.

One thing I can't get a grasp on is why Hugin doesn't calculate lens distortion parameters on the A & B images. This is paramount in creating a good panorama. Perhaps due to the varying camera position.

When taking panoramas, a few rules:

  • Use a tripod. If possible align the camera on the tripod with the no-parallax point (often called the nodal point, but really the entrance pupil). Aligning the camera at the nodal point requires a special adapter.
  • If you don't have objects close to the camera, you can successfully create good panoramas without proper nodal point alignment. This looks like you held the camera at arms length and rotated about the axis of your body creating large shifts in the camera position. There are many tutorials on the Internet discussing how to shoot a pano and probably many posts on StackEx.
  • If you don't have a tripod, you can take a hand-held series of shots if your body is stable (lean against something so your body doesn't wobble). Use your finger as an axis point near the nodal point of the lens and rotate the camera about the axis point. Try to keep the axis point (your finger) as stable as possible.
  • Use manual focus and exposure. Do not change focal length between shots.
  • When creating the panorama, eliminate control points on clouds and plants (wind tends to make plants move).
  • Practice using a simpler subject matter where you have good lighting and a stable subject matter (no clouds or plant matter that moves in the wind). Having object(s) near to you will tell you if you are rotating the camera about the nodal point.
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    tiny persnickety footnote: technically, the no-parallax point (or center of the entrance pupil) of the lens is not the same as a lens's nodal point(s). Most panorama sites use the term 'nodal point' incorrectly.
    – inkista
    Apr 4 at 3:21

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