Why creating panoramas? I think they show scenery much better than single shots. Additionally panoramas can be used to create very high resolution images from every object with normal resolution cameras. Especially if you want to create posters from your shots an image stitched from many photos has an enormous quality compared to the single photos.
This is a step by step guide to create nice panoramas from the shots you' ve made. But remeber, this is only a brief guide, which helps to get started. The tools I explain in the following are free and easy to use.
Panorama created with these tools
Make your shots
Well this is the easiest part, but most of the problems that may occur while creating panoramas are based on bad images. The best solution is to carry a tripod with you. While hiking easy or not too exhausting trails this is fine, but while climbing there would be only a very few people, who carry a tripod with them. To solve this problem and to lighten your rucksack, you' ll have to care about a few things while taking your shots.
- The first choice you have is how to align your shots. I prefer vertical alignment, because your panorama will get bigger and you' ll have a greater vertical view-angle. On the other hand you need to take a lot of shots to get a fully 360° panorama (about 25).
- Most of the panoramas I' ve seen on the internet have a lot of sky and only a little bit of landscape. This can be avoided by starting to shoot images with the highest mountain/building/... visible. There you can adjust the ratio between sky and landscape because nothing else will be higher and you don' t have to change the angle of your lens to the horizon.
- While you turn around try to create an overlapping area of at least 1/5 from image to image. Additionally try to keep the horizon at about the same position.
- Don' t zoom or change something of your camera settings while you' re taking photos. If your camera supports it, turn off any automatic helpers.
Install the required software
There are a lot of commercial programs available, which do the stitching for you, but why spending money on software, if there are free programs to do this? I' ve tried some commercial programs, but the results satisfied me only on some panoramas. Some time ago I accidentially found some open source tools, which work fine and produce excellent results.
Here is the list of programs, you' ll need and where you get them:
|autopano-sift (700KB)||This (optional) program can be used to align your images automatically. The results are quiet fine, but I prefer aligning myself. Unfortunately this tool is only available for Windows systems.|
|Panorama Tools (1MB)||This is a collection of programs, which perform all the stitching into one single image.|
|hugin (3MB)||A graphical user interface for Panorama Tools. Available in several languages.|
|enblend (1MB)||This program cares about image composition and make the seam between the images (nearly) invisible.|
All of these tools are available for Windows and Linux (excluding autopano-sift). I' ll not focus on installation here, because every tool has installation instructions on its homepage. Additionally I' ll focus on the Windows tools, because I think most of the SP users have a Windows system. The only difference to other OSs may be different button alignments within the GUI, but the basic functions are the same.
Short description of the stitching process of these toolsautopano-sift
creates a lot of so-called control points on every image. After this it tries to find these control points on the other images. These point combinations are used to algin/stretch/rotate the images to make them fitting. After this step hugin
may be used to edit these control points and to add vertical and horizontal alignment lines. After that Panorama Tools
start their work and stitch the images. Optionally enblend
may be used to improove the quality of the image.
Preparing your images
If you scan your images from slides, I recommend to use the program PTAverage, which helps to decrease noise made by your scanner. PTAverage is included in Panorama Tools. To use it you need to scan each image several times (don' t move it). After scanning your shots, you have to feed PTAverage with them, which calculates an "average image" from your scans which improves quality. To use PTAverage open a console and type the following to average pict001.jpg - pict003.jpg (PTAverage asks you for an output filename):
ptaverage pict001.jpg pict002.jpg pict003.jpg
After doing that or downloading the images from your camera look at them and adjust color balance and/or brightness of your images if they differ too much. Many image editors (GIMP, Photoshop, ...) offer tools to do so. This helps enblend to hide image borders visible after the stitching process.
Aligning your images
As mentioned above, you can align the images by yourself or let autopano-sift do it for you. I prefer doing it myself, because then you' ll have control about this process. Additionally it is not difficult and helps to improve quality, because a human mind "sees" difficult sections (like objects close to the lens or long ridges) and can put more control points in there.
First of all we need to start Hugin and add images to our new project (File -> New). I recommend to start with two images and after aligning them add the next one and so on.
Start either with the image on the left or right side. This helps to handle control point generation.
After adding two images to the project' s image list, click on the Control Points-tab and look for an interresting spot on the image and click it. Here it is the top of a mountain. It doesn' t matter if you click in the left or right image window.
It is important to have two differen images in the left and right window, because with the control points these two images get stitched together.
Now you have to find the same spot in the other image. After clicking it Hugin adjusts the circle, which marks it. If it raises an error message, don' t bother and adjust the circle by yourself by simply clicking and moving it to the correct position.
If everything is fine click the Add button. Even if you don' t have to align the circle by yourself check if the contents of the circles are about the same, before adding the control point to the list. Add about 10-15 control points.
Now we are ready to optimze the images. To do so click the Optimizer-tab.
Here you need to do three optimizations in the following order:
|1||Positions (incremental, starting from anchor)|
|2||Positions (y, p, r)|
|After optimizing the Panorama Preview shows the actual panorama. If there are some parts that are not matching, add some more control points and if the image looks fine add the next image to the panorama.|
After you have added all images to your panorama you' ll propably get something like the preview on the left side.
Well, this is nice, but not the thing we want to have. Now we have to give Hugin some horizontal and vertical alignment lines to align the hole panorama.
These lines are created like control points, but the left and right image window show the same image and you have to create lines within it.
|The left image shows the result after re-optimizing the panorama images. You' ll have to create several alignment lines on several images. Looking at the preview, you' ll see if you need more of them.|
Now we' re ready for a first low resolution test stitch, to see if our panorama is ok. Click on the Stitcher-tab and select JPG as output format and adjust the output size of the panorama. To get a feeling of the dimensions click Calculate Optimal Size to see how big your panorama really is. Choose about the half of this size (speeds up the calculations).
If everything is fine change the settings of the stitcher to Multiple TIFF file output and use the maximum size of the panorama. Click on Stitch now! and get a cup of coffee, because your PC' ll have to work for several minutes.
If something is wrong within your panorama add some more control points or alignment lines and retry.
If you stitch your images into one .jpg file you' ll see the seams of each image. The enblend tool helps to hide these areas. If you have chosen the Multiple TIFF option before stitching, you' ll get several (huge) .tif images. enblend is a command line tool, which combines these images into one. The following command line executes it (copy enblend.exe into the directory, where the .tif files are):
enblend -v -m 512 -o pano.tif panosrc*.tif
The v option enables command line output of what the tool is doing. The program needs a lot of memory, which can be limited by the -m option. I recommend to use the half of your system ram (here: -m 512 limits the RAM used by enblend to 512MB). The o option tells enblend where to store the output file (here pano.tif) while the last parameter are the input files.
Finishing your panorama
After enblend has finished processing, the panorama is nearly done. The only thing left to do is to open the created .tif file with an image editor (doesn' t matter which one). Select an area with no black background and copy and paste it into a new image and save it as .jpg.
Here you can do some final quality improvements like sharpening. If your image editor supports it, select the highest quality level when saving the file.
Happy panoraming and I hope this helps you to create a fine one.
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