Difference between revisions of "Hugin FAQ"

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If the panorama looks nice but the horizon is curved, there are two ways to improve the image and straighten the horizon. First, try optimizing the view by selecting "Positions and View" as the optimization mode and run the optimizer afterwards. By clicking "Calculate Field of View" in the "Stitcher" tab and displaying the preview window afterwards you can check if the image has been improved.
 
If the panorama looks nice but the horizon is curved, there are two ways to improve the image and straighten the horizon. First, try optimizing the view by selecting "Positions and View" as the optimization mode and run the optimizer afterwards. By clicking "Calculate Field of View" in the "Stitcher" tab and displaying the preview window afterwards you can check if the image has been improved.
  
If it is still curved, you have to add vertical guide control points in the "Control Points" tab. Usually two [[vertical control points]] are enought to straighten the horizon nicely. Often edges of buildings, poles or other man made structures provide good vertical lines. To add a vertical control point, switch to the control point editor and select the same image on both sides. Place a control point on the left image on the upper area of the vertical feature. In the right image, select a control point on the lower area of the features, and press the Add button. Once the new point has been added, its type should automatically switch to "vertical Line". You might want to switch off the auto-add and auto-estimate options while doing this to avoid naggy dialogs while adding this guide points.
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If it is still curved, you have to add vertical guide control points in the "Control Points" tab. Usually two [[vertical control points]] are enough to straighten the horizon nicely. Often edges of buildings, poles or other man made structures provide good vertical lines. To add a vertical control point, switch to the control point editor and select the same image on both sides. Place a control point on the left image on the upper area of the vertical feature. In the right image, select a control point on the lower area of the features, and press the Add button. Once the new point has been added, its type should automatically switch to "vertical line". You might want to switch off the auto-add and auto-estimate options while doing this to avoid naggy dialogs while adding this guide points.
  
 
Two points that are roughly 90 degrees apart provide the best effect.
 
Two points that are roughly 90 degrees apart provide the best effect.
  
See also the related perspecitve correction tutorials: [http://hugin.sourceforge.net/tutorials/architectural/en.shtml hugin tutorial on perspective correction], [[Perspective correction]], [[Leveling_a_Finished_Panorama]]. While these are concened with correction of the perspective in one image, the same technique can be used for
+
See also the related perspecitve correction tutorials: [http://hugin.sourceforge.net/tutorials/architectural/en.shtml hugin tutorial on perspective correction], [[Perspective correction]], [[Leveling a Finished Panorama]]. While these are concerned with correction of the perspective in one image, the same technique can be used for
leveling a panorama
+
leveling a panorama.
  
 
== Postprocessing ==
 
== Postprocessing ==

Revision as of 07:17, 18 August 2006

General Questions

Control Point creation

How do I add control points

The control points editor is quite powerful, but its usage is probably not obvious on the first try. Here are some ways the developers use the Control Point panel:

1. Selecting control points in 100% zoom.

This method needs some scrolling, if big images are used. You might want to try the fit to window zoom setting in that case. Switch to the Control Points tab, and use the following settings:

Zoom: 100%
[X] auto fine tune
[X] auto add
[X] auto estimate

Click on a prominent feature in the left image. If the image pair already contains control points, hugin will try to select the point in the other image. If its the first point in this pair, click near the same feature on the right image. The second point will be placed and fine tuned automatically. If you are not happy with the placement, both points can be moved by dragging them to a better position. Press the "f" key to fine tune the point in a small area.


2. Selecting control points in fit to window mode.

I uses this mode if I need to set points on big images. Switch to the Control Points tab, and use the following settings:

Zoom: fit to window
[X] auto fine tune
[ ] auto add
[X] auto estimate

Click on left image. The image will be shown in 100% view. Within the detailed view, click on a prominent feature. If the image pair already contains control points, hugin will try to select the point in the other image. If its the first point in this pair, click near the same feature on the right image. The point will be placed and fine tuned automatically. If you are not happy with the placement, both points can be moved by clicking at the desired position. Move the point close to the desired feature and press the "f" key to fine tune the point. When the points are on the same feature, press the right mouse button, or press the "a" key to add the control point pair. It will then be shown in the list below the image.

How do I scroll both images at the same time?

Try pressing the shift key while moving the mouse. The control key or the middle mouse button can be used to scroll only the image under the mouse cursor.

Common problems when creating a panorama

How do I straighten a curved horizon?

If the panorama looks nice but the horizon is curved, there are two ways to improve the image and straighten the horizon. First, try optimizing the view by selecting "Positions and View" as the optimization mode and run the optimizer afterwards. By clicking "Calculate Field of View" in the "Stitcher" tab and displaying the preview window afterwards you can check if the image has been improved.

If it is still curved, you have to add vertical guide control points in the "Control Points" tab. Usually two vertical control points are enough to straighten the horizon nicely. Often edges of buildings, poles or other man made structures provide good vertical lines. To add a vertical control point, switch to the control point editor and select the same image on both sides. Place a control point on the left image on the upper area of the vertical feature. In the right image, select a control point on the lower area of the features, and press the Add button. Once the new point has been added, its type should automatically switch to "vertical line". You might want to switch off the auto-add and auto-estimate options while doing this to avoid naggy dialogs while adding this guide points.

Two points that are roughly 90 degrees apart provide the best effect.

See also the related perspecitve correction tutorials: hugin tutorial on perspective correction, Perspective correction, Leveling a Finished Panorama. While these are concerned with correction of the perspective in one image, the same technique can be used for leveling a panorama.

Postprocessing

Why is the ICC profile of my input images not preserved?

Since hugin 0.5 and enblend 2.4 ICC profiles in the input files are transfered to the output panorama. Please update to a current version.

How can I postprocess the image using multiple layers in The Gimp?

Unfortunately, The Gimp can't read PSD formatted files generated by PTStitcher, and the multiple TIFF output it produces is cumbersome to use. There are two possibilities to work around this:

  • Use the nona stitcher, to output to a multilayer TIFF format.

This will will produce a multi_layer.tif file, that contains all remapped images, cropped to their bounding box. This will save a lot of space, compared to a "traditional" PTStitcher layered output file, where all layers have the full panorama size.

Unfortunately, The Gimp 1.2 and 1.3 can't load multilayer TIFF files. Please use Gimp 2.0 or later.

  • If you need PTStitcher features not supported by nona, you can also use tif2xcf, to combine the multiple TIFF output into a multilayer XCF.

Unfortunately this requires a lot of memory because it stores each remapped image in a layer with the size of the final panorama.