Get spectacular super wide angle results using ordinary cameras and lenses
Super wide angle lenses are usually exotic items of camera optics with a similarly exotic price tag. But you can, with a little bit of patience, get impressive wide angle results - using your ordinary 'standard' lens. This tutorial applies to users of cameras with interchangeable lenses and cameras with integrated lenses.
So how do you get a super wide angle view out of a lens that isn't particularly wide? The answer: stitching, or taking several images and seamlessly joining them together to form a new composite image that really looks like it was taken in one go.
Called panorama stitching or photo merging, the technique is simpler than you might think thanks to very clever software that you may even already have as part of the image editing software package you routinely use. Cameras now often have built-in options for automatic stitching although results can be hit and miss. For best results, follow the advice that follows and use a good software-based stitching program on your computer.
(Click image above to expand view in a new window) If you don't have an ultra wide angle lens, you can still get wide format panoramic views like this...
...or like this (above). (Click image above to expand view in a new window)
Above you can see that the panorama of St.Mark's Basilica and the Doge's Palace in Venice, photographed from the top of the Campanile di San Marco, is made from four separate photographs. And you may notice that the four donor images were taken vertically. This avoids excessively thin ribbon-like images that suppress the size of details that we want to see in the view.
Let's compare a view taken with a super wide angle lens with a stitched panorama of the same scene:
(Click image above to expand view in a new window)
The above photo was taken with a lens with an equivalent view of a 14mm super wide angle lens. That's a 114 degree field of view (between opposite corners of the frame). To get significantly wider than that from a single exposure you would need to use a fish-eye lens.
(Click image above to expand view in a new window)
And above is the same scene but constructed from four vertical photos. There is much more width recorded and in some ways the image looks more natural, with less accentuated perspective. Where this kind of panorama stitching does compromise is in the straightness of some image features, like the bank of the cane, which is clearly curved instead of straight. Depending on the lens and focal length you choose to use, you may not be able to capture as much foreground or sky as a super wide angle lens.
Shooting conditions for multiple-frame panoramic photography also need to be constant. Each constituent picture needs to have the same exposure in order to avoid visible differences in the final result. If the sun is constantly going in and out because of fast moving clouds, you will be very fortunate to get decent results as the exposure values of each shot will differ too widely.
Camera settings:
Zoom: assuming you have a zoom lens, you don't necessarily have to set it to the very widest focal length. The venice pano was taken using a zoom that could go as wide as 28mm (135 or full frame format equivalence), but I chose 38mm. Experiment to get the best framing.
Exposure: take a test shot of the central part of your intended panorama - or at least the part of the panorama that is of most interest. Check that the exposure is correct - either by viewing the image on the camera's screen and/or checking the exposure histogram. When you are happy, note the shutter speed and aperture and change the camera settings to manual, if you can. Dial in the settings you have recorded. Using manual ensures that the exposure will be consistent across all the images that will be used. Especially when hand-holding the camera, ensure that your shutter speed is fast enough to avoid camera shake. It's highly recommended that you use a tripod that has been leveled. If using a tripod, switch and image stabilisation modes off. IS can actually create unwanted blur when the camera is tripod mounted.
White Balance: If you can, use RAW format to record your images. This will allow you to fine tune the whit balance later, if required. If you are shooting JPEG images only, if you can, switch from auto white balance to a manual white balance mode that corresponds with shooting conditions. Again, you don't want any differences, this time in colour, from one shot to the next.
Focus: Focus only once if you can. One method, which works with many types of camera, is to use the autofocus, then immediately switch to manual focus and then avoid moving the focus control.
Here are the four donor shots used in the earlier example. I have used four images, but you can use more or less. Some programs will even allow you to use more than one row of images. Notice how a generous overlap between each frame has been factored in. Image stitching programs are very clever, but they can't deal with gaps from one image to another. Try to keep the camera as straight as possible and avoid tilting the camera from one shot to the next. As I said before, if you want to get good consistent results, a tripod will be a big advantage.
Software
There was a time when the ability of image stitchers was very variable. I'm using Photomerge in Photoshop here and the most recent versions of Photoshop do seem to incorporate a much-improved version of Photomerge. There are many other free and paid-for image stitching solutions to choose from, and your regular image editing application, like Photoshop Elements, or Paint Shop Pro. Windows Live Photo Gallery has a panorama stitcher, and this is a free application for Windows 7 users. There are many other options you can find with a little searching online.
(Click image above to expand view in a new window)
In Photoshop CS4 go to the File > Automate > Photomerge... menu option.
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Next, you need to select the images that will form the final joined-up result. On the left there are various geometry options. By all means experiment with these options, but to start with Auto is the best choice. You can also let Photomerge correct vignetting (darkening in the corners of each frame) and geometric distortion. The latter really only works properly if you have a very carefully aligned sequence of images.
(Click image above to expand view in a new window)
And here is our result. The wandering border is a result of the combination of the massaging of the images to join them up seamlessly, and also the fact that used the camera hand-held and clearly didn't keep the camera as level as I could have. You can see the shape and position each donor image forms its part of the final result by examining the layers palette.
Next all you need to do is crop the wobbly border and you end up with a super wide angle shot, without the need to use an expensive super wide angle lens.
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