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Creating Panoramas With hugin Photo Stitcher

vía Digital Photography School de Peter Carey el 10/06/09

hugin-icon Recently I posted the article 8 Guidelines To Taking Panoramic Photos With Any Camera followed by 20 Great Stitched Panorama Examples, both of which garnered a fair amount of "But what do you use to create them?" questions. While I have typically used commercial ($$$) software, a number of readers pointed out the virtues of a freeware program called hugin.

I'm all for using free software when available but at times it can be lacking compared to commercial counterparts. I'm very pleased to report this is not the case with hugin. Robust beyond my simple means, this program should be in every digital photographers virtual toolkit. It's easy to use, has a lot of room for manual modification and produces excellent panoramic images.

This post will center on the insanely simple task of creating a panorama from pictures shot with a Canon SD630 point and shoot camera. While the program has many advanced features, I'd like to show just how easy it is to get started creating panoramas on your computer. And one great thing about hugin is it works on Windows, Mac OSX and Linux! Screen shots for this demonstration will be done on a PC. Let's get started!!

First, you'll need to download hugin. The download page can be found here. After downloading, install the program according to your operating system's instructions. Upon starting up hugin (and clearing the hints pop-up) you will see the simplistic screen below. (click image for full size view)

It's simple and ready to go out of the box. Click "1. Load images…." and a file selection box will appear. Simply click on the first photo in the panorama set, hold down <shift> and click on the last photo you'd like included. Then click "Open" (I know, Windows is still backwards that way as you're not really opening anything, just selecting). Your images will be loaded and checked for lens type, camera type , focal length and focal length multiplier.

Just a few steps left!! Click "2. Align…." and hugin will start a process to evaluate your images and find control points. Control points are points found in an image that hugin can identify as mostly unique. It uses these control points to match up photos. In the 8 Guidelines post I mentioned an ideal overlap of 30%. This is where that overlap comes into play. The more overlap, the more control points hugin can match between the two images and correct for camera orientation or lens curvature. This step is automated (and you can go back later to select or remove your own control points) and a new screen will pop up telling you how many points were found, like this:

Depending on a number of factors such as computer speed, file sizes and location, number of images selected and available processor power, hugin will chug through your pictures one at a time. At this point, if you have a lot of data to crunch, it might be a good time to go grab a bite to eat or get some other work done. The panorama I am using as my example, which contains 12 images taken with a 6MP point and shoot, took about 15 minutes on a 2.8GHz Windows XP machine, for what that's worth.

When hugin is done, it will tell you how many points it can connect and if it thinks things will work well. If there aren't enough points, you may have to set some manually. To do this, click on the "Control Points" tab, then select an image for each window (left and right) for which you want to match points. If hugin has found some points already, you'll be greeted with a very colorful window like this:

Now, click on any point on the left image. Hugin will zoom in allowing you to more precisely position the crosshairs on your target. Once elected, hugin will attempt to find the same spot on the image in the right window, displaying its best guess. If that guess is not good enough, manually click and drag the crosshairs to the desired spot. This zoom gets down to a pixel by pixel locating and can be very precise. Click the "Add" button on the bottom right of the screen and your new points are added (you an also check the box for "auto add" if you find hugin is doing a good job of matching your selections and don't wish to click "Add" each time).

It's time to click back to the "Assistant" tab and let hugin create your panorama!! Click on "3. Create panorama…." and after you tell hugin where to save the finished file, you'll get another screen letting you know the status of the process. It can have some crazy stuff as seen below:

And that's all there is to it!! Ok, there's actually one more step depending on the output of the file. In the most basic mode, you will still need to crop the image. Initial output will look something like this:

I personally like having more control over my crop and don't mind this raw stitch look. It's fairly simple to import the image into my favorite photo editing software and crop to my liking. It also gives options to change things up a bit as seen in the final image options below:

And there you have it! Panoramas made easy and free! Hugin has a wealth of tools to help manipulate the stitch process including the ability to auto level for exposure and angles. Luckily the folks who have worked on hugin have also put out a good users manual, located here, that will help explain the ins and outs of all the tabs and tools in hugin.

If you're looking for further encouragement on what hugin can produce, check out the flickr tag hugin for over 14,000 examples!

Post from: Digital Photography School - Photography Tips.

Creating Panoramas With hugin Photo Stitcher