Hugin Photos tab
Hugin Photos tab
The Photos tab is a combination of the "old" Images tab and the "old" Camera and Lens tab as being used in Hugin versions untill 2012.0.0.
The Photos tab is used to:
- Manage the images in a hugin project.
- Edit the positions of the images in the final panorama.
- Edit the lens settings.
Multi-selection can be used to change the parameters for multiple images.
User interface modes
The User interface modes, being Simple, Advanced and Expert determine the layout and (number of) options in this tab.
The Display radio buttons on the right side determine the layout and what is displayed in the images table. What is displayed in the table, e.g. the number and kind of columns, per Display option is again user interface mode dependent. For example: In the Display option General the column Stack no. in the images table (see above (enlarged) screen capture) is only visible (and available) in Advanced and Expert mode.
On the right side of the screen you will find the Group by: drop down box with immediately above it the label showing in which user interface mode the screen is currently being used. The available options are displayed in the table below.
Images table options
The images table has a few events ("mouse action options"). If you double-click an image inside the table the Edit image variables popup is displayed and the image parameters can be examined and/or edited. If you right-click inside the table a context menu is opened.
This tab contains a "Context menu", sometimes better known as a "right-click menu" which is accessible in the images table.
There are three possibilities:
- A "right-click" in the table without any image(s) selected
- A "right-click" in the table with one image selected
- A "right-click" in the table with multiple images selected.
|No image selected||One image selected||Multiple images selected|
|Edit image variables...||Edit image variables...|
|Add individual images...||Add individual images...||Add individual images...|
|Add time-series of images...||Add time-series of images...||Add time-series of images...|
|Remove selected image(s)||Remove selected image(s)|
|Anchor this image for position|
|Anchor this image for exposure|
Images can either be added with:
- the button Add individual images...
- via the context menu (Add individual images... and Add time series of images...)
- via drag and drop.
Add time series of images... adds all images with a similar file modification time as the selected image; if the the project is empty then a file dialogue opens to allow you to pick this initial file.
Edit image variables
The Edit image variables option when double-clicking an image in the image table or via the right-click context menu will open a popup with four tabs being Positions. Lens, Photometrics and Camera Response. The options in this popup are also dependent on the user interface mode.
Automatic creation of control points can be done by pressing the Create control Points button (if you select just some images, then control points will only be found for those selected). With the dropdown selector in front of the Create control Points button, you select which control point generator (feature matcher) to use for detecting the control points and adding them to the project. These control point generators (feature matchers) need to be configured in Preferences->Control Point Detectors. Hugin comes standard with cpfind configured for a few situations. The Hugin Preferences can be used to set further options and to add new tools to the list or another instance of the same Control Point Detector with other settings (like for rectilinear images or for (full) frame fisheye for example.
The Remove control Points option from the context menu option Control Points does exactly what its name suggests, it removes control points between the selected images, or all control points if no image is selected.
On the Image Positions tab, the orientation of the selected image(s) in the final panorama can be specified by yaw, pitch and roll angle (in degrees); and (only) in Expert you can also specify the X, Y, and Z translation parameters.
You can set the parameters to 0 in this popup but also via the right-click Reset menu with it's sub-menu options.
By selecting an image in the images table and via right-click Anchor this image for position you can indicate that a particular image shouldn't move when optimising with the hugin Optimizer tab. Only one image can be the anchor, and by default this is the first image in the project.
The tab Lens on the Edit image variables popup allows you to examine or modify the values for the degrees of view, Radial Distortion, Image Center Shift and Image Shearing.
Usually lenses do not project images exactly according to the selected projection type, but suffer from distortions. In many cases the distortions are acceptable for single image shots, but they need to be corrected when stitching a panorama. The a, b and c parameters are used to remove that distortion. They are applied radially from the image center, which can be moved by changing the d and e parameters. These a, b, c, d and e parameters are the basis of the panotools lens correction model.
Scanned images might also suffer from image shearing. This can be corrected using the g and t parameters.
The distortion parameters usually vary with the focal length, and to a lesser degree with the focus. The link checkbox indicates whether the parameter is linked or not. A linked parameter is forced to the same value for all images with the same lens number. This is the default for the HFOV and distortion parameters. If a parameter is not linked each images is allowed to have individual values for the respective parameter. This is useful if a different zoom or focus setting has been used for some images. If scanned images are used, they are usually not perfectly centered, and each image should have individual d and e parameters.
By right-clicking an image in the image table and selecting the context menu option Anchor this image for exposure you can specify that a particular image should be used as an unchanging reference anchor when optimising Exposure or White balance. Usually this should be the image with the least under or over-exposure or the image with the most typical White balance.
Image orientation can be linked between a group of images if they are already aligned. For example, if they form a bracketed (exposure) set shot on a sturdy tripod. To do this, select all the images in the stack, and press the New stack button. You can also move images into an existing stack without selecting all the other images in the stack: press Change stack... and enter the stack number you want the selected images to join. The stack number of each image is given in the table.
If your images form approximately aligned stacks, you can create stacks as usual, select all the images and then uncheck Link by the image position. Approximately aligned stacks are common when you shoot bracketed sets handheld, or in windy conditions with a light tripod. Hugin will remember that the images form a stack, but does not force the image orientation and translation to be the same across the stack. This is useful for specifying stacks when you have a Panorama with Stacks control point detector configuration before control point generation. You do not have to manually mark approximately aligned stacks in other circumstances, however.