The kind of result I'm after is illustrated with this panorama:
Drag the picture around to make the panorama turn over 360 degrees. Press shift to zoom in, control to zoom out. On OSX left-right scrolling the scrollwheel of the mouse will also let you turn the image.
The panorama is not very sharp, because I reduced the detail so it would not be too heavy for the web.
(Other examples on this site: Barcelona, Venice).
The panorama was made in Salzburg on a sunny day of November 2008. It is composed of 12 pictures taken with an ordinary small camera (Canon Ixus 80IS) and stitched together with QuickTime VR Studio.
The camera and the stiching software are not very important. This page is about how to obtain the original pictures to start with.
Since this panorama is composed of 12 shots, I obviously clicked the shutter 12 times and I turned the camera through a certain angle between shots.
So that is the basic operation: take several pictures in succession, turn between pictures.
Here are miniatures of the twelve pictures I went home with:
But there are a number of precautions to be taken.
The Ideal Case
Ideally you would take a number of photos perfectly equally spread over the 360 degrees, all pointing perfectly straight at the horizon. You would turn the camera exactly around the centre of its lens (where the pinhole would be if it were a pinhole camera).
Note also that you will turn to your right, so that the succession of photos will line up easily when you view them on your computer. Always turning to your right is not an obligation, it just makes life a little easier later on.
Possible equipment
The ideal case is of course impossible to achieve, but with some equipment you can get very close. The stitching software will do the lining up, blending of overlap etc. to produce a high quality panorama.
If you want to make a hobby out of high quality panoramas, then you should probably get a good tripod and other instruments. Something like this:
The tripod carries a turntable, the camera is mounted on the turntable so that the centre of the table corresponds to the centre of the camera's lens. The turntable has several rings with clicking-in positions, allowing a choice of dividing the 360º into 8, 12, 24 or 36 sectors.
Such a tripod plus turntable is a heavy and large device, not usually taken on a holiday trip. The equipment pictured weighs almost 4kg without the camera!
Practical panorama shooting without special equipment
Obviously it is much easier to come close to the ideal case using a turntable with divisor, but in the following I give my own recipes to obtain a reasonable result without anything else than a simple consumer camera. Unless you make panoramas as a serious hobby, forget the tripod.
Since we're not using any special equipment, we're going to do this with: our hands and body (holding & turning), our eyes (matching the photos and overlap) and our memory (remembering where we started from).
Considerations
These are practical problems to keep in mind:
Since you are going to turn over 360 degrees, there will be a point at which the sun will be in your back. It will be difficult to see what's on the LCD screen of today's small consumer cameras. Best is therefore to use a camera with a viewfinder. Be prepared for this problem if your camera does not have a viewfinder.
Since you are going to turn over 360 degrees, you better look around first if that is not dangerous. Don't try to make a full 360º panorama standing close to a cliff's edge, on the side of a busy road, on top of a staircase etc. without being aware of the dangers.
A classic, simple 360 degree panorama is a set of photos that can be wound around a virtual cylinder. The lines of sight of the photos must lie in a plane. They must not make a cone like in this illustration:
A bad way of turning the camera
The centre of each photo should be on the horizon. This is the most difficult part of making a panorama, with or without a tripod: to turn on a cylinder instead of a cone. For example, from a mountaintop the impulse is to point down rather than at the horizon. Then there is much more overlap at the bottom of the picture than at the top, and that's lethal. The inverse impulse (pointing up) happens in town.
Also do not point up or down to get interesting things into place, photos must line up and anything that is too high or too low will be cut off anyway. If you camera has lines in the viewfinder, use those to ensure that shots are nicely aligned with the horizon and with themselves. In town use the eye level of people, even if you have to imagine people (ask yourself where the eye level would be if there were a person there, far away?).
Shooting level is also difficult when the landscape is very different around the 360º. For example when there is a mountain in the back and a valley in front, I tend to point slightly down over the valley part and slightly up over the mountain part. I just can't help it. But then of course the bottom parts of the valley pictures are cut off and so is the top of the mountain. Exactly what I instinctively wanted to avoid! So keep it level and never mind what does not get into the picture. In the Salzburg panorama above I could nevertheless not avoid small differences. The raw pictures show this clearly when they are lined up:
As I turned, I instinctively tried to get the hilltop in, pointing the camera slightly upwards. But that was clearly stupid since the hilltop necessarily got cut off in the final result. All I achieved was to cut off also the bottom of all other pictures. The result retains anyway only the image inside the red cropping rectangle:
Don't tilt the camera sideways. Remember that the sea is level and should appear so in the photos. Stitching pictures that are rotated by more than a few degrees is difficult if not impossible.
All shots need to be exposed at the same settings of aperture and speed. Therefore you need to switch the camera to manual. If your camera has no manual setting then there is a trick explained further on.
Since you turn over 360º you will have some shots directly into the sunlight and others away from the sun. The best exposure is some average. To get the right exposure, I set the speed & aperture for a shot that is at 90º from the sun.
Shots away from the sun will then be underexposed and those towards the sun overexposed, but not by any significant amount.
getting the average exposure
(never mind the funny landscape, I don't know where it is ;-)
Don't try to make a panorama at all if the lighting changes fast (e.g. moving clouds). Whatever the virtues of PhotoShop, it is nearly impossible to adjust colour balance for different lighting exposures.
If you want a good vertical angle of view, hold the camera vertically (portrait). This needs more shots to get around 360º, but as we are not using a tripod there will be differences in aiming, pointing slightly up or down, and those will lead to some cutting off anyway, therefore a great vertical angle is good. You will then need at least 12 pictures.
If you want good vertical view then also use the widest angle your camera allows.
Once the exposure is set, choose a direction to start from. This will usually be the direction that you want the viewer to see when the panorama is opened. This "pan" angle can be set to a different angle during construction of the final panorama file, so it is not important. The next point is much more important, so ignore a good starting view in favour of a good start object.
Observe very well some object in the start view. You will have to turn through 360º and come back to this point. If you make a few extra shots it's not important but if you lack even just a little overlap at the end, then the panorama cannot be turned fully. Therefore it is important that you remember exactly where you started.
Take your first shot, pointing at eye level or at the horizon. Take note of an object that is in view and close to the right edge of the frame.
Turn so that object at the right edge is now at the left edge. I.e. turn to your right. Be sure to stay with your feet on the same spot. Take the next shot.
Continue doing this until you see the object you started from again. Always turn the full 360º, do not worry that bystanders may think you are crazy to take multiple shots of that blank wall in the back or whatever "uninteresting" parts there may be. Do not worry too much about things moving in the scene. But don't hesitate, just keep clicking and turning.
You are now Finished.
Set the camera back to automatic.
I think that if you re-read this, it will all be very straightforward and the rules follow logically from the desired result.
Ultimately the number of shots and the turn angle between shots depends on the lens angle used, but it is usually at least 8 photos, and at least 12 if portrait.
Consider overlap: you need some, but not too much either. Say something like 10% to 20% of the width of the viewfinder. Having no overlap in just one pair is lethal: the panorama will not turn 360º. More or too much overlap is much less of a problem. My Salzburg panorama had much more overlap than 10%, in one case there was so much that an entire picture could be removed from the series.
The sequence must fit to a cylinder and you can understand why. I have with great pains corrected conical views on badly taken panoramas, but it needs a lot of PhotoShop work.
Ideally also the camera should turn around the centre of its lens (where the pinhole would be if it were a pinhole camera). But as you are holding it to your head and our heads have a finite diameter, the camera is turning around a point that lies some 10 or 20cm behind that point. This is not important for a landscape but becomes very important for an indoor panorama. In the case of a panorama withmany objects close by, try to keep your head back (this looks funny again to bystanders, but never mind them) so that the camera turns around its center.
Summarised recipe
OK, let's repeat this:
Look around for danger.
Set the camera to manual.
Decide on the zoom angle and whether to use portrait or lanscape.
Set the exposure for a shot at 90º from the direction of the sun.
Pick a start position and remember an object in that position.
Take successive shots:
remember an object at the right side of the frame,
turn to get that object at the left side of the frame (having an overlap of approximately 10% of the frame)
always point horizontally, use the horizon or the eye level of people far away.
don't tilt the camera sideways.
Continue until you see the start object again and take that as the last shot.
Set the camera back to automatic.
Trick for cameras with no manual exposure setting
On small consumer cameras you can always fix the exposure by pressing the shutter release half-way down. That way you can set the exposure again in between two shots by again pointing 90º away from the sun. That is a very tedious way to get the same exposure for each picture but it does work. It also taxes your memory because you have to remember the objects etc. between the real shots and the aim to fix the exposure.
