By Steve Gosling
The popularity of long-exposure photography shows no sign of abating. The Live Bulb function on Olympus cameras helps to take any guesswork out of the process. Here’s how to use it.
Long-exposure images have become very popular in recent years, particularly in the field of landscape photography. Static elements (trees, buildings, fence posts and rocks, for example) contrasted against moving features such as water or windblown clouds and foliage during an exposure of several seconds can create ethereal, moody images. They can transform a relatively mundane scene into an evocative photograph. However, there is a danger that long-exposure photography is becoming a cliché – technique for technique’s sake; a reflection of current fashions or the photographer’s obsessions, not something chosen to reinforce the message they want to convey about their subject. This is true of any technique that’s used blindly, without thought given to its appropriateness to the subject.
Using a technique with a specific aim in mind is the key to success. For example, using a long exposure to accentuate contrasting textures – the rough texture of stones, rocks or wood (jetties, fallen trees) against the smoothness of blurred water – or to create a sense of energy and dynamism in an image. The landscape is rarely static – it constantly changes over seconds, minutes, weeks or years, and a long exposure can convey that sense of restlessness by capturing movement in one frame.
Subtlety is also important. Not every image requires an exposure of several minutes – sometimes an exposure of a few seconds can convey a sense of movement more effectively. This is particularly true of waterfalls, for example – a very long exposure will turn the water into a substance resembling cotton wool, whereas a shorter one gives a sense of movement but also retains the texture of fl owing water.
One of the attractions of long exposure photography is that the resulting images record a dimension of the world we can’t see with the human eye. Our brain takes a snapshot of what we see and is not capable of recording a scene as it evolves over seconds or minutes.
These images are difficult to pre-visualise; it’s hard to predict exactly what the camera can see. This can be one of the great attractions – it adds an element of luck or chance to the final image. For example, windblown clouds can provide unpredictable shapes or patterns in the sky to enhance the mood of the finished photograph. But this uncertainty can also prove incredibly frustrating. Particularly when it comes to exposure. Taking a four-minute exposure at dusk (when there’s usually little chance to repeat the shot) only to discover that a six-minute one was required can be exasperating to say the least.
Not any more, though, thanks to a unique feature introduced by Olympus to its OMD range of cameras – Live Bulb and Live Time.
WHAT IS LIVE BULB/LIVE TIME?
This feature gives a regular update on the exposure as it is progressing, while the shutter is open. So the photographer is able to see the image ‘develop’ in-camera and stop the exposure once the shutter has been open for sufficient time to give a correctly exposed photograph (see Step by Step guide).
The interval of the update can be set from 0.5 seconds to 60 seconds with the timing set by the photographer depending on the total length of exposure. So, for example, with an exposure of eight seconds you might require an update every two seconds, whereas with an exposure of two minutes a 30-second update may be more appropriate.
In Live Bulb mode, the shutter remains open for as long as the shutter is depressed. In Live Time mode, the shutter release has to be pressed once to open the shutter and then pressed again to close it.
Live Bulb/Live Time appeared on the first OM-D – the E-M5. However, this gave only an updated view of the image. On subsequent OM-Ds (the E-M1, the E-M10 and most recently the E-M5 II), the histogram was added. This useful addition is far more reliable than trusting only the image view on the camera’s rear display panel (the panel will view differently depending on the lighting conditions, and the brightness of the screen also influences how the image appears).
With the E-M10, Olympus also introduced Live Composite Mode (subsequently added to the E-M1 and included with the E-M5 II at launch).
Live Composite mode also takes long exposures, but several of them, and only adds new light sources to the final picture. It’s great for capturing star trails or firework displays.
Image noise is always an issue with long exposures – the longer the shutter remains open, the hotter the sensor gets and the more digital noise becomes apparent. To get the best image quality, it is important to use a low ISO setting and to turn on the Long Exposure Noise Reduction feature. This will double the exposure time, but leads to higher-quality files.
It’s worth noting that long exposure noise is more of a problem with the Olympus OM-D E-M1 than the other cameras in the range. This is the price paid for its more sophisticated autofocusing system.
READING THE HISTOGRAM
To make the most of the Live Bulb feature, it’s important to understand the histogram – what it is and how you use it to best effect.
Most simply, the histogram shows the distribution of tones in an image from pure black (on the left-hand of the display) through shades of grey to pure white (on the right-hand side of the display). If possible, it is important to adjust the exposure to avoid the loss (or ‘clipping’) of both highlight and shadow detail – that is, to make sure that the distribution is not so far over to the right or left that information is lost.
If you’re shooting Raw files (as opposed to JPEGs) it is also important to remember to ‘expose to the right’ – that is, to bias the exposure towards the highlight end of the display without losing detail in the highlights. This will give the best-quality information to work with when processing the image. So in practice, when using the Live Bulb/Live Time features of the Olympus cameras, keep the shutter open until the histogram display moves across to the right hand side and close the shutter just before highlight details are lost.
Successful long-exposure photography (with the Olympus range or any other camera) requires good technique and some additional bits of kit.
A good quality tripod and head are a must. Even the smallest and lightest of cameras will need to be mounted on a solid support. A cable release will allow for the shutter to be fired without touching the camera and thereby avoid the risk of causing camera movement. And if your camera has a mirror then use mirror lock-up to prevent any possible vibration caused as it moves out of the way at the start of the exposure.
Finally, if you want to take long exposures in brighter conditions then a neutral-density (ND) filter will be required. Lee Filters (among others) makes varying density (2, 3, 6 and 10 stop) filters for this purpose.
STEP BY STEP – HOW TO TAKE CREATIVE LONG EXPOSURES WITH THE LIVE BULB FEATURE
1. Select the Live Bulb function in the Menu (Menu> Custom Function E>Live Bulb).
2. Select the Live Bulb interval required for the particular exposure. In this case the interval has been set to 8 seconds. Next, turn the Exposure Mode dial to M for Manual.
3. Adjust the shutter speed beyond the longest timed setting, i.e. 60 seconds, and the Live Bulb setting will be found.
4. Open the shutter using a cable release. The Olympus release has a lock setting which is useful for very long exposures.
5. Watch the histogram move to the right as the exposure ‘develops’ and end the exposure before highlight details are lost, i.e. before the histogram moves off the right-hand edge of the display.