Panoramic photography (part 1) - technique and equipment

Panoramic photography is a fascinating part of photography, which is especially popular in landscape photography, but also in urban areas. Particularly on large screens or large-format prints, the motifs appear very impressive and allow the viewer to immerse himself more in the details and the entire scenery than with the usual image formats. With the help of virtual reality, panoramic images can also be discovered on mobile devices in an interactive way – be it imposing mountain landscapes, brightly lit city backdrops or quiet and mysterious mountain forests.

What is panoramic photography?

Panoramic photography describes the stitching of slightly overlapping single shots (single-line or multi-line) into a single, large photo. The final result does not necessarily have to be an extremely wide image, even photographs in the classic 4:3 or 3:2 format can be panoramic shots consisting of several individual images.

In this and further articles I would like to discuss the techniques and equipment for panorama photography. I would like to start with some thoughts about the question when this kind of photography makes sense.

Avoiding converging lines

What the telephoto lens is for wildlife photographers, the wide-angle lens is for landscape and cityscape photographers. The term wide-angle actually refers to everything below a focal length of 35 mm (full-frame format); usually, the range of 14-24 mm is referred to as wide-angle format. Where the telephoto lens reduces the image detail, the wide-angle lens does just the opposite and makes it possible to fit “more subject” into a single photo.

What sounds good at first glance, however, comes with a price. This is particularly noticeable when photographing buildings, trees or other subjects with clear, straight lines, because the strong distortion at the edges of the image causes the so-called plunging lines. This is the perspective distortion at the edges of lenses, which is particularly pronounced with wide-angle lenses due to their design.

The reason for this is the size of the field of view, which with a wide-angle lens is larger than the sensor area of the camera. As a result, the peripheral areas of the depicted subject have to be squeezed together, so to speak, so that everything fits on the final image.

This effect of plunging lines and distortion in general is not necessarily a problem. However, it is particularly noticeable in architectural photos, buildings or other subjects with clear lines (such as trees). In landscape photos, especially those taken at a fair distance from the subject, the effect becomes so small that it is usually negligible, which is why a wide-angle lens is a popular companion for landscape photography.

There are various ways to avoid converging lines. This can be the subsequent processing with image processing software, whereby here by the straightening always image material (and thus resolution) is lost. This effect is clearly visible in the image above, which was straightened purely in post-processing with Adobe Photoshop Lightroom. Another option, especially in architectural settings, is to use a tilt-shift lens, but this is quite an expensive investment in a lens with a very limited range of use. The third option is to take a panoramic photo, which is an effective way to avoid plunging lines, especially in landscape photography.

In the panorama above, taken in a mountain forest in the Valais illuminated by the evening sun, it is nicely visible that there are no falling lines in any of the tree trunks (even those at the edges of the picture), but all the trees are standing straight. This shot would not have been possible with a wide-angle lens.

However, the effect of distortion does not only occur with vertical, straight lines, but is also quite visible in landscape photographs. However, it is not as noticeable there because even the distorted image has a coherent composition.

Panoramas for an (extra) wide field of view

Probably everyone knows the impressive effect of wide landscape photographs that literally immerse the viewer in the motif. When such panoramas are viewed on appropriately high-quality screens or as a professionally printed print, a completely different effect is created than with a simple photograph. The reason lies in the perception, which in a panoramic photo is more like the perception by the human eye in real nature. In both cases, we can complete and expand the image by slightly turning our head, whereas with a simple photo, it’s over very quickly. This goes all the way to 360° panoramas (often referred to as roundshots), which allow the complete capture of the photographed environment, possibly even up to the vertical.

Another field of application of such panoramic photographs are interior roundshots, as they are often made for example in hotel rooms or also interiors of cars or mobile homes. The basic principle is the same: several individual images are combined to form a large-scale overall panorama and then published online as a virtual reality roundshot for interiors using a special web viewer.

Meanwhile, even some public webcams, especially in tourism, use this technology and allow the viewer to get a comprehensive picture of the destination in real time.

Maximum resolution

A last point that can almost be called a side effect is the maximization of the resolution that is achieved with panoramas consisting of several single images. This can be especially important for large format printouts, but also for display on large and high quality monitors, especially if the panoramas are zoomable, as is the case with the panoramas on our website, for example. The higher the resolution, the more you as a viewer can enlarge the image without the individual pixels becoming visible. However, this also comes along with a corresponding file size: large panoramas with 65’000 pixels side length are almost 1 Gb in size.

Equipment for panoramic photography

For panorama photography you need a camera, of course. Unfortunately, it’s not only the camera and a lens, but you need some more items, namely a tripod, a panorama head as well as a nodal point adapter.

Since this field of photography is rather niche, there are not so many manufacturers of panorama heads or nodal point adapters, whereas the selection of tripods is rather large. One manufacturer with an extensive and high-quality range for panorama photography is the German manufacturer Novoflex, but suppliers such as Manfrotto also offer individual components such as panorama heads or nodal point adapters. Most of these products can be combined with each other, as they all use the industry-standard 1/4″ or 3/8″ threads.

A stable tripod

The linchpin of panorama photography is a stable and sufficiently high tripod. Basically, any tripod can be used here on which the panorama head can be mounted. However, you should pay attention to a certain buffer range for the load capacity of the ball head or the leveling spherical cap, since altogether quite a bit of weight comes together. If the ball head can’t bear this weight, the camera could sink imperceptibly, which in turn would ruin your individual images.

A ball head is not absolutely necessary. I use a tripod without a ball head for panorama photography, but with a leveling calotte that allows me to compensate for minor unevenness in the ground using the integrated spirit level. Whether the tripod has carbon legs or not doesn’t really matter. More important is a stable stand, since you’re working on the camera mounted on the tripod and its position shouldn’t change during shooting.

The panoramic head

A panorama head is basically simply a plate that can be rotated at least horizontally, usually gridded, with a mount for the camera on one side and a thread for the tripod on the other. The grid can be adjusted on some models, so that the appropriate distance from one grid step to the next can be adapted to the lens used (for example, 6, 8 or 10 steps for a 360° rotation). With the help of an integrated spirit level, the panorama head can be aligned exactly horizontally. This is important for truly horizontal panorama shots that do not slope towards one direction even in post-processing. The adjustment itself is done, for example, thanks to a leveling calotte, a kind of movable hemisphere that allows a certain fine adjustment within 15-20°.

The nodal point adapter

In the professional field and for elaborately produced panoramic shots, a so-called nodal point adapter is often used. This is a mount for the camera that, when mounted on the panorama head, ensures that the pivot point of the tripod and the optical pivot point of the camera and lens are aligned. Figuratively speaking, the optical pivot point of a camera with mounted lens sits somewhere in front of the camera “in” the lens – but the camera itself rotates on its tripod mount and thus has a pivot point that is offset by several centimeters. A nodal point adapter can avoid the effects known as parallax errors, in which the distances between photographed objects in the image differ slightly per individual image due to the different rotation points. When stitching the individual images together, this quickly leads to errors that even no software can eliminate.

A small patience game is the adjustment of the nodal point adapter to the respective lens and camera, which, by the way, is usually mounted in portrait format in panorama photography. Unfortunately, the exact positions of the individual components cannot be calculated, but must be determined manually. Here, several vertical lines in the camera’s viewfinder, one behind the other and slightly offset from each other, are brought into alignment by fine adjustment on the nodal point adapter so that the distances are always exactly identical, even when the panorama head is rotated. The important thing to remember about this exercise is that it has to be done once per lens – so you should do yourself a favor and keep the number of lenses you want to shoot a panorama with within manageable limits.

With most systems, the individual components of a nodal point adapter have scales printed on them (see in the pictures above), which make it possible to quickly find the correct setting again. I included a printed piece of paper in my panoramic photography kit that lets me know exactly and quickly what settings I need for the various rails and adapters.

The overall panoramic head and nodal point adapter system is often available for purchase as a single-line or multi-line set. With multi-line sets it is possible to take a two- or multi-line panorama with for example 2 x 10 images instead of just one panorama with 1 x 10 images. The first number here refers to the number of lines that make up a panorama.

Lens and focal length

I use exclusively one single lens with a focal length of 50 mm (full format) for panorama photography. On the one hand, this is because I am too lazy to do the setup of the nodal point adapter for multiple lenses, and on the other hand, because 50 mm with its neutral representation of the size ratios is generally a good compromise of field of view and distance for the human observer. It is not for nothing that this focal length is often referred to as the standard focal length.

The light intensity is rather secondary for a lens in panorama photography, because thanks to the tripod, the exposure time plays only a minor role while the ISO value is as low as possible at the same time.

Camera settings for panorama photography

Anyone who has ever taken on a climb of several hours with heavy luggage including camera equipment and then looked forward to the result of panorama photography probably knows the feeling of having to realize later during panorama stitching that the images are unusable. All the single images look quite nice on their own, but unfortunately they can’t be used for a panorama because they might have become too dark, are out of focus or look uneven. I speak from my own experience…

So what settings should you pay attention to when shooting with a panorama system?

Camera mode

I usually rarely shoot in manual mode, most of the time I use aperture priority and only worry about setting the aperture, ISO and exposure compensation, while the shutter speed is selected automatically. For panorama photography, on the other hand, I always choose manual mode. This has the following background: I want to achieve that every single image is taken with the exact same parameters. Imagine the image of a flowing river, photographed with different exposure times. In one image the water is frozen in motion and sharp, in the other it is blurred and soft due to longer exposure time. Blending these two images is likely to present any stitching software, no matter how good, with unsolvable problems. For this reason, you should always choose the manual mode of your camera.

Automatic white balance (AWB)

The automatic white balance is often activated and in most cases it makes perfect sense. Unfortunately, this mode leads to a different color tone and different brightness nuances in the image when you pan the camera – this is also a problem that cannot be solved when composing the individual images. In addition to the manual mode, you should also set the appropriate manual white balance (cloudy, sunny, artificial light, etc.).

Camera stabilizer

Since the camera is mounted on a tripod, you normally don’t need a stabilizer. On the contrary, it can cause your image to be blurred. There are few things more annoying than finding out that one out of ten frames is garbage – and I guarantee it will be a frame right in the middle. So: stabilizer off and mount camera firmly on tripod and panorama head.

Telephoto lenses are rare when shooting with a panoramic head. But if you want to use such a setup, please keep in mind that camera and lens sometimes oscillate for a short time after you have touched the tripod, for example to turn the panorama head to the next position. So it’s better to wait three to four seconds before pressing the shutter button to avoid vibrations despite the tripod.

Remote shutter or self-timer

The shutter mechanism also falls into the category of shaking: make absolutely sure that you press the shutter remotely or using the self-timer. The risk of the camera shaking minimally and ruining the image is just too great. Especially in windy conditions, however, this can be a bit of a challenge, so sometimes weighing down the tripod with a backpack can help. In extreme cases with very strong wind, it can be useful to hold the tripod while shooting and shoot with the stabilizer activated and short exposure times to minimize shaking.

By the way, speaking of wind, never underestimate the force that wind has on a camera with a large telephoto lens on a tripod with a panoramic system. It’s better to hold on too tightly than to risk expensive collateral damage to your camera and lens.

ISO

By using a tripod you should and can keep the ISO as low as possible (for most cameras this means ISO <= 100). Especially if you want to present your panoramas online in an interactive viewer, zooming in is another way to interact with the image. Here it would be a pity if image details would be lost due to image noise caused by high ISO values.

Aperture

Which aperture is the right one for panorama photography? You can probably already guess the answer: it depends. Basically, you aim for a continuous depth of field in the image (and thus also in the panorama), which is more in favor of medium to higher aperture values. Depending on the situation, however, it may also be to shoot with the aperture wide open. It is important to set the aperture manually and consistently so that there are no different areas of sharpness in the various individual images. You should also use the hyperfocal distance to ensure that all areas from front to back are in focus in each individual image.

Histogram and exposure compensation

Panoramas in which you shoot subjects of varying brightness as the camera pans are a bit of a challenge. Here you can either create an HDR panorama (HRD stands for High Dynamic Range) or try to find a compromise in brightness. The brightness you choose should make it possible in post-processing to darken images that are too bright and lighten images that are too dark – ideally without losing details in the image. Such situations are especially common in scenes with the sun setting or rising on one side and darkness falling or coming to an end on the other. In such a case, if you set your exposure compensation based on the images with sun (i.e. darken the image), the images without sun will be completely black – the other way around, the images with sun would be completely overlit, while the darker areas would be correctly exposed.

The only thing that helps here is trying out different exposure correction settings and some practice to be able to estimate how much correction is too much later on during post-processing.

HDR panorama photography

I don’t want to go into detail about the relatively complex and elaborate HDR panorama photography in this article. With high dynamic range photos, several images are taken with different exposures and then superimposed and blended in post-processing so that the respective ideally exposed areas are adopted in the final image. For a panorama photo with ten individual HDR images at three exposure levels each, you would have to take a total of 30 photos (3 x 10 images each consisting of an underexposed, a normally exposed and an overexposed shot). In post-processing, the individual images for the panorama must first be created from the HDR images and then stitched together.

Since this process is relatively error-prone and time-consuming, I would like to dedicate a separate article to this topic in the future.

Do a test run before you get started

Once you have set up your setup, I recommend that you create a test panorama to make sure that all settings on the camera and on the panorama head and nodal point adapter are correct. Check the following points in particular:

• Is the depth of field correct, even in places where the foreground is closer to the photographer (this is often the case at the edges of the panorama)?
• Is the exposure correct, so that all images are within a healthy range on the histogram? You can easily correct certain nuances using image editing software, but a completely overlit sky or pitch-black valley sides even the best tool can’t save.
• Is the grid of the panorama head chosen correctly, so that all images have a certain overlap (vertically and horizontally for multi-line panoramas)?
• Is the cropping of all single images correct and doesn’t, for example, a single mountain top poke up very far? There is a risk that after stitching the images and cropping the panorama, parts of the motif are cut off or reach so far to the edge of the image that it looks visually unattractive.
• Are all images sharp and not blurred?

Try to take the test shots under similar lighting conditions as the planned panorama to avoid unpleasant surprises, especially with the brightness.

What can go wrong with panoramic photography

Out of ten panoramas taken, I probably throw half away again. This is mostly due to the following points:

• Moving clouds: look nice, but if they move quickly, they are the devil’s work, which can ruin the entire panorama, because the images cannot be superimposed without errors. Here you can only try to conjure up something useful with a lot of interventions in the stitching software. Often, however, this does not succeed and the panorama is unfortunately useless. The only thing that helps is watching the weather report, the sky and in case of doubt, admitting that it’s just not meant to be today.
• Waves on the water surface: here the same problem arises as with moving clouds. The wave in the next overlapping single shot is guaranteed not to occur in the same place as in the previous image. The result: staggered wave crests and creative blending attempts by the stitching software that are at best convincing as abstract artwork. Again, the fewer waves the better, or the greater your distance from the water, the less noticeable the waves.
• Wobbling trees or plants: these can ruin your picture in various ways. On the one hand, longer exposure times can lead to a muddy mess of moving leaves or grasses – not exactly the desired result for an otherwise crisp panorama. Or, on the other hand, the branches swing back and forth so much that stitching the individual images together is no longer possible here either.
• Changing light conditions: the sun can suddenly hide behind clouds (and then stay there for the time being) or when taking a picture at sunset or sunrise, the overall light changes and becomes brighter or darker. Here, only patience, an open eye as well as speed when taking pictures will help.
• People: yes, they can also crash your panorama, especially in a city environment. Even with a long exposure, in which you can easily eliminate moving objects, there will certainly be at least one person lingering so awkwardly on the stairs that your panorama shot of Cologne Cathedral is unfortunately decorated with a selfie-taking tourist. The only help here: Patience, patience and more patience – or get up early and be there before everyone else. Then, however, the city sweeper might just be parked in front of the cathedral….
• Use of a polarizing filter: it can be useful to use such a filter – but you should keep in mind that you turn your camera and that this changes the necessary, preferably right-angled irradiation by the sun and the effect of the polarizing filter decreases. In the worst case, parts of your panorama will be brilliant in color, while others will look rather colorless.

As you can see, there are a lot of factors that could throw a wrench in your plans for such photos. For panoramas in landscape photography, wind and changing light conditions in particular are potential problems that you should keep in mind.

Panorama photography at dusk

The panorama of the Swiss Rhone valley in the autumn evening twilight took me a total of five attempts, each time combined with travel as well as about 30 minutes of ascent to the photo location. Besides unsuitable weather with bad light (and avoidable problems like a panorama system forgotten at home), the complexity of shooting during twilight also played a big role.

Each of the 22 frames was shot with a long exposure of 30 seconds (to allow for the light trails of the moving cars). The twilight period in autumn progresses relatively quickly, and since the long exposure time alone means that almost 6 minutes pass just for the shots, this proved to be a challenge: within 6 minutes, the light changed so much that the left end of the panorama had a completely different brightness level than the right end – with the added complexity of extremely bright images in the area of the setting sun on the one hand, and almost completely dark valleys on the other. Finding the right settings in terms of exposure compensation therefore proved to be quite stubborn.

So when photographing panoramas at dusk, we can state the following: the longer the exposure time of the individual images, the more the changing light conditions have to be kept in mind. All the more so, as it is not a good idea to change the settings on the camera between the individual shots.

Panorama photography – is it worth the effort?

In the end, everyone has to decide this question for themselves. Simple panoramas are of course possible with simple means, even the smartphone cameras now offer usable results for this, but can not resolve the distortions that occur. For professional commissioned photography, panoramas are an interesting approach to ensure individuality and a high recognition value. For this, tools like a panorama head with nodal point adapter are essential and provide the necessary tools to enable wide shots with high resolutions.

Mit der reinen Aufnahme der Einzelbilder ist es jedoch nicht getan. Im Anschluss daran steht die Nachbearbeitung sowie das Zusammenfügen des Panorama, welches ich in einem zweiten Artikel in unserem Fotografie Blog beleuchten werde.