Amateur photographers looking for a quick way to create panoramas from a series of photos should give AutoStitch a shot. It does quite well with minimal user intervention, but those who desire extensive control over the minute details should look elsewhere.
Here’s the quick version of how to create a panorama using AutoStitch:
- Take a series of pictures with at least 20-30% overlap. Ideally you’ll do this with the camera mounted on a tripod to minimize the chances that you won’t keep the horizon in a consistent place in all the photos.
- Copy the pictures to your computer.
- Download Autostitch here then unzip it. No installation is necessary, just double click the .exe file to launch it.
- Optional: Go to “Edit –> Options” to change some of the options.
- Go to “File –> Open” to open the pictures in your series.
- AutoStitch automatically stitches the pictures and gives you a panorama from your series of pictures.
Jim Doty has a great post that outlines the basic functions of the application plus some tips and tricks. I figured out a few of the tips on my own by trial and error before finding his post, and the others were very helpful too (such as the file quirk order, which I was still working on).
Here are two of my own tips if you have a single directory in which several photo series are located:
- When opening photos for creating the series (Step 5 above), switch the AutoStitch ” Open ” dialog box view to thumbnails. It will be easier to pick out which photos you are looking for.
- Be sure to rename “pano.jpg” to something different after creating each panorama. That’s the default output name, and AutoStitch always drops it in the same directory as the photo series. If you don’t rename “pano.jpg” before creating the second panorama, it will overwrite the first one.
My approach to creating panoramas is basically this: create it at the highest possible size and resolution, then crop and resize (in Photoshop) as necessary depending on how I plan to use the finished product. This is accomplished by setting (in Step 4 above):
- “Output Size” to “Scale = 100%”
- “Matching Options” to “Scale = 100%”
- “Other Options” to “JPEG Quality = 100″
Beyond those changes, I haven’t tinkered too much with the settings because I’ve been pretty happy with the output.
If you’d like to try customizing your experience a little more, the ReadMe.txt that accompanies AutoStitch.exe offers the following info:
- Output Size — You may specify the output size based on the desired output width, height or relative size compared to the input images. Be sure to check the radio button beside width, height or relative size appropriately.
- Blending Method — Select linear or multi-band blending. Multi-band blending is slower but gives better results.
- Gain Compensation — Selecting gain compensation causes AutoStitch to modify the brightness of the images so that they are consistent with each other. This causes dark images to become brighter and bright images to become darker. To amplify the effect, increase the value of gain sigma. Note that this can cause saturation. If this occurs try decreasing the gain sigma or gain mean.
- Crop Settings — You can specify the rendering range in terms of angles theta (longitude) and phi (latitude). AutoCrop selects these ranges automatically. Make sure AutoCrop is not selected if you wish to set the ranges manually.
- Matching Options — You can specify the size of the images for SIFT feature extraction and some parameters for the RANSAC algorithm here. If images fail to match, try decreasing alpha and beta, and increasing the SIFT image size. If incorrect matches are found, try increasing alpha and beta.
- Orientation Settings — AutoStraighten uses a heuristic method to straighten out wavy panoramas. The manual orientation settings allow you to specify extra rotations for the panorama e.g. to centre it.
- Image Rotation — If the input images are rotated, select the rotation of the input images here.
- Other Options — Choose a JPEG quality setting in the range 75-100.
- Setting the System Memory allows the program to allocate resources more efficiently. If you get an “Out of Memory” message, try decreasing the System Memory.
What are the shortcomings? There are a couple, one of which is that it doesn’t correct (at least automatically) the distortion from your camera lens. It also doesn’t correct lighting (and color) differences between the photos in the series. That will manifest itself as darker and lighter bands (each band corresponding to one picture) in your photos depending on the settings that your digital camera automatically used for each photo. Another thing I noticed is that the horizon in the panorama usually drops lower the further left you look.
The following pictures demonstrate some of the shortcomings I’m talking about. These are very scaled-down examples of panoramas that I’ve created with AutoStitch (I apologize in advance if they’re too wide for your screen – use the horizontal scroll bar):
There is more complex software available, but it’s better suited for professionals (plus most of it is fairly expensive). Those of us who take pictures strictly for the fun of it will enjoy the free AutoStitch because of its ease of use and the reasonable quality of its output.