Copyright Michael Karbo, Denmark, Europe.
Chapter 28. Multi shooting
Most cameras can take more than one exposure at a time. You hold the release down while the camera shoots one image after the other. This technique can be used in a number of different ways and gives a photographer a whole lot of new possibilities.
Figur 108. A series of images taken in a few seconds can enable you to catch different expressions on your mother-in-law’s face!
You can, for example, let the camera take three or five pictures, where the exposure is altered a little bit every time (bracketing). This is really smart in situations, where you are not quite sure of the lighting. Another possibility is just shooting five exposures in less than 2 seconds – this is very effective when taking shots of children or in other situations, where you want to catch a particular face expression.
Serial recordings in several ways
The whole idea of serial recordings is for the camera to take three, four, five or more images immediately after each other (the individual exposures are called frames). The newer the camera is, the better the serial recordings will probably be because they require a lot of work from the camera’s image computer. Serial recordings are also called continuous recordings or motor function. A serial of images can be taken in a number of different ways, each of which fulfilling its purpose:
Continuous recording. Here, for example, five images are taken in rapid succession, as fast as the camera can. Just hold the release button down, and let the camera snap away. After the recording it will take a few seconds for the images’ data to be saved on the RAM card – then you can shoot a new serial.
Top 5. Here the images are taken in an unending stream but it is only the last five that are saved from the moment you let go of the release.
Bracketing. Here the exposure parameters are altered for every shot in the serial. It might be the exposure, the white balance or the focus, which is set a little differently for every new shot in the serial.
Best Shot Selector. Here the camera’s image computer itself selects the best picture in the serial.
These functions are found in several variants but they are very alike. The biggest difference from camera to camera is the speed and the capacity for serial photographing. Some cameras, for example, are so fast at processing the images that they can continue taking and saving images in serials as long as there is room in the RAM card. But most models can only take a handful of images in a serial.
Figur 109. This table shows examples of different cameras’ capacity for continous shooting.
Figur 110. Nikon has a special system called Best Shot Selector. Here you let the camera itself select the best of, for example, five exposures (left). The selection can be done on the basis of the image computer’s analysis of the image’s areas of light (Highlight BBS), shadow area (Shadow BBS) or the histogram.
Selecting drive mode
If you take several shots of the same subject, then the chances for ”a perfect shot” is much bigger. Which is why serial photographing is an unbelievably brilliant aid, which, at the same time, is easy to operate.
The function is activated with a little press button, where you can see several frames or small camera icons on top of each other:
When you press the button, you can choose between the different types of drive modes the camera in question has.
Serial recording is a really good function – especially if you have a big RAM card. If you are photographing a group of people, you can ask them to move about a little from side to side while you take a serial recording in rapid succession. One or two of the exposures are certain to be much better than the others, which can easily be deleted in a computer.
With Top 5, Final 5 or Last 5 the camera shoots away as long as you hold the release button down. Only the last five exposures are saved on the RAM card when you let the release go. This is really smart if you are waiting to photograph the pack in the Tour de France, which is coming closer at a lunatic speed …
In the menu system above there are several versions of serial recording. The difference between them can be whether the focus, exposure values and white balance can be locked with the values the camera finds in the first frame. If everything is locked, then the serial can be taken very quickly. With a so-called AF serial things happen rather more slowly because the auto focus might change from frame to frame. This is a rather flexible menu for serial photographing. (Olympus 5060Z)
Bracketing is a smart variant of serial photographing. When you activate it, the camera takes three or five exposures every time you press the release. The point is that the camera’s settings are changed a little bit with every exposure. Typical variations are:
These functions are fine tools for getting a perfect exposure.
Figur 111. Here are three exposures taken with bracketing. The exposures are respectively underexposed and overexposed corresponding to one whole diaphragm step. You can choose the best exposure of the three yourself and delete the other two.
Better chance for good lighting
Every image has both light and dark areas. The dark areas reflect very little light and are, therefore, the areas where the image sensor isn’t exposed well. On the other hand, the subject’s light areas reflect lots of light, which gives a powerful exposure on parts of the image sensor’s surface.
In an ideal image, we can see details in both the darkest and the lightest areas. In practice, it is very difficult to achieve this. It’s a little bit like parking a big car in small parking lot – there doesn’t have to be very much imprecision before you hit one of the sides.
Figur 112. The bracketing here gives three variants of the same image with 2/3 diaphragm’s difference in the exposure. The difference isn’t very big, but it is there!
Very often the images are either a little overexposed so that details disappear (burn out) in the light areas. Or else the image is underexposed so that details in the dark areas disappear. Use the histogram here as an aid when you assess the exposure. But if you seriously want to feel sure, then the camera’s exposure bracketing is a brilliant aid.
With exposure bracketing the camera takes three or maybe five exposures with varying lighting. These will be a little underexposed, normal and a little overexposed. You can determine yourself how much the deviation should be from exposure to exposure. Bracketing with 1/3 or 2/3 EV (exposure values corresponding to diaphragm steps) give three or five good exposures, where you can easily (maybe with support from the histogram) select the perfect lighting.
Bracketing can be a great help in achieving the ”perfect” photo.
Figur 113. Settings for exposure bracketing. You have to select an EV value; the exposure has to vary from (1/3, 2/3 or one whole diaphragm step). In the menu system on the right, you can also determine if the bracketing should be made with three or five exposures. (Fujifilm og Olympus)
Better focus or white balance
Focus bracketing works in a completely different way. It is especially used with macro exposures (photographing of objects only a few centimeters away). It can be very difficult to get a camera to focus sharply here. So you take three or five exposures, where the object is focused on a little differently. There is a much better chance that one of the exposures has the right focus.
Finally, the more professional cameras often have white balance bracketing, where three or five exposures are taken, where the colour temperature, for example, is altered with 200 degrees for every shot. This is really a great idea, if it is important to get a required colour tone exactly.
Please note, however, that both the exposure and the white balance can be adjusted after exposure, if you take photographs in a RAW format. This makes these bracketing functions somewhat superfluous. Not the focus bracketing, however; if an image isn’t sharp, nothing can alter that.
The technique behind serial photographs
In cameras from the olden days, you could get a motor to pull the film reel quickly through the camera body so that you could take 36 exposures in a period of a few seconds. Sports photographers used this method earlier, when they wanted to catch a Laudrup in the right position, just before he scores. The photographer probably had to take about 15 images to get the right one.
But a digital camera works in a completely different way; the individual exposures have to be, so to speak ”developed” immediately. At least they have to be processed and stored on a RAM card, and this takes time.
Taking the individual images functions without problems. The image sensor can take 10 or more images in a second and it can go on as long as there is enough power in the camera. The limits are in the processing.
Every image fills quite a lot in the camera’s RAM and they have to be processed in the image computer before they can be stored on a RAM card. All this takes time.
Serial recording is a technological area, which is being strongly developed. Purely technically the camera is equipped with a big RAM buffer, as it is called. This is a very large portion of internal RAM (up to 1 gigabyte), which functions as temporary storage for a serial of exposures. The larger the buffer is, the more exposures the camera can take in one go.
When the buffer is filled up with frames you have to wait a while before you can take a new serial. The image computer has to edit the existing data and reproduce it as image files in the RAM card.
Figur 115. The image sensor can continue taking one image after the other. The problem is processing the exposures.
The images are first collected in a so-called buffer, which has enough room for perhaps five images. The images are then sent from the buffer individually to the image computer, which ”digests” them and spits the processed image files out again onto the RAM card.