What do we mean by exposure compensation?

What do we mean by exposure compensation?

For all that our cameras are capable of rendering the world in glorious Technicolor, their light meters are remarkably simple: they can only 'see' in shades of grey. When a light meter attempts to judge the correct exposure for a scene, it does so under the assumption that the scene's average brightness is middle grey (18% grey), which is exactly half-way between absolute black and bright white.

Exposure explained

Exposure explained

As a photographer one of the first things that you need to understand is exposure, or how to control light to create an image. If you're new to photography or have just picked up a camera with manual control for the first time, we suggest that you start here. Learning how to manipulate light to achieve the shots that you want is a life-long project, but these are the foundations.

Dare to stray into bulb mode

When setting your shutter speed, have you ever wound the adjustment wheel so far into long exposure that you've gone past seconds and found 'B' or 'Bulb' on your screen? Or maybe you've noticed that you have a 'B' option on your mode wheel, somewhere between Manual and Custom settings? This is bulb mode, and it allows you to control the duration of the exposure for precisely as long as you would like. It's perfect for exposures in excess of the 30 seconds that most cameras have as their longest shutter speed, or for when you need to be in control, for example if you're practising high-speed photography. First, a quick word on why it's known as 'bulb' mode. Haje has a much more thorough explanation here, but it doesn't have anything to do with light bulbs. It's from back in the day when you could control your shutter speed using an air bulb connected to your camera.

'B'? What the hell does that do? (Picture thanks to Triggertrap.)

When your camera is in bulb mode, you open the shutter by depressing the shutter release button; as soon as you raise your finger off of the button, the shutter will close. Seeing as it isn't terribly convenient to stand with your finger on your shutter release button for minutes or even hours on end—and it's not fabulous for camera-shake, either—most people use bulb mode in conjunction with a remote shutter release. And a tripod, but that's probably quite obvious.

Plenty of remote shutter releases come with a locking mechanism, so that you don't need to hold your finger down there, either. However, if you go for something such as our much-beloved Triggertrap, you can select from a variety of different modes to control your super-long exposure, including a timed release that lets you set the duration of your exposure down to fractions of a second, a star-trails setting, and even a bulb-ramping option to fine-tune exposure during very long time-lapse recordings.

Late night in East London

Even if you're shooting at night, your camera's sensor will be able to detect far more light than you think it can, especially with a very long exposure. Consequently, using a small aperture is recommended. If you're photographing during the day, you might benefit from a neutral density filter to prevent unavoidably over-exposing your images, too.

It is worth bearing in mind that using bulb mode can drain your battery enormously. Don't set off to capture star trails with a less-than-fully-charged battery. Take a spare if you have one, too. It's a complete waste to maroon yourself in the middle of nowhere with limited light pollution only for your camera to keel over halfway into the exposure.

Waterfalls, shot using bulb mode. (Picture thanks to Triggertrap.)

Now that you know what bulb is, what can you do with it? Perhaps you'd like to try some long exposures of landscapes? Or maybe capture some smooth, milky-looking water tumbling from a fall. You might want to try your hand at a star trail, or have a go at light painting. You could even grab a flash adapter and have a crack at some high-speed photography and burst some water balloons. So many options presented to you with so much time from bulb mode!

Back to basics with a pinhole camera

A few weeks ago I was contacted by Elvis Halilović, the man behind the ONDU Pinhole camera company, asking me if I'd like to try out one of his handmade, wooden pinhole cameras. It's not the sort of offer I'm likely to decline. Last week my entirely gorgeous 135 Pocket Pinhole arrived through the post. On Monday I took advantage of glorious sunshine and the flourishing abundance of the allotment and headed out with a few rolls of film to see what the camera could see. Today I collected an envelope of developed images from the shop in town. One ONDU 135 Pinhole camera, with an approximate focal length of 25mm

How did they turn out? Actually not all that brilliantly. The film was expired, which has resulted in all of my photos having a rose pink cast. Despite the very useful exposure guide provided by ONDU, judging shutter speed was a very hit-and-miss affair that was counted in pink elephants and almost everything is over-exposed. My little Lollipod stand is a perfect match for the ONDU pinhole, but I've not mastered opening the shutter without disturbing the camera, and of course the longer exposures means motion blur, so everything is hazy. And without a viewfinder, you're guessing at just what the camera can see, so what's in the frame isn't necessarily what I'd anticipated would be there.

Proof of the pinhole

But the truth is, none of that matters. What matters is that I'm proud of these pictures and that I had fun taking them. I enjoyed experimenting with exposure times and attempting to determine what the camera could see. I recalled the anticipation of my childhood, when I'd send films off to be developed and have no idea what would be sent back to me. It was, in fact, the most fun that I've had with a camera for a very long time.

I won't deny that I had a few frustrations, but they weren't enough to deter me. The ONDU requires you to tape the film onto the receiving spool and count one-and-half rotations to wind on between frames. Loading the film was a bit tricky and I succeeded in breaking one roll with a heavy-handed winding action. There were a couple of unintentional double-exposures, too. No one said this was going to be easy, or indeed fast, though.

The ONDU pinhole in action

Perhaps the best tip that I have is to head out with a notebook when you're shooting, to record the lighting conditions and exposure time for each frame. When I go out next time, if the lighting conditions are similar, I'll know to open the shutter for a fraction shorter duration. If the conditions are different, I'll be making more educated guesses. Whatever the light, I'll be having more fun.

Pinhole photography itself is intuitive, with the requirement to judge and estimate and guess. It's also visceral and plays on your emotions of surprise and vexation. The more that you practise it, the better you'll become, not just at pinhole photography, but at the general discipline of photography. It pulls you back to the founding principles of expose and compose: a simple concept but with a nuanced practice.

The opportunity that a pinhole camera gives you is to play with light in a box: photography in its most deceptively simple form. If that doesn't intrigue and inspire you, and remind you what's wonderful about taking pictures then I'm not sure what will. Get hold of a pinhole camera and go back to basics; you won't regret it.

Struggling to understand the exposure triangle? Try thinking of it as a glass of water


There are three things that affect an exposure: speed, aperture, and ISO. They work in a triangle to achieve an exposure.

When you give with one you take with another to ensure that you don't over- or under-expose your shot. In your early days of setting your exposure manually, it can be a bit tricky to remember how they fit together. But if you think of exposure as a glass being filled by water from a tap, it might help. Here's how it works.


Think of aperture as how much you open the tap. The wider you open it, the more water flows into the glass. Open the aperture wider and you let more light into the camera.

Shutter speed

If aperture is how far you open the tap, shutter speed is how long you open the tap for. If you open it for a long time, a lot of water comes out. If you open it only briefly, just a little water comes out.


The final control in the exposure triangle is ISO. From the perspective of our water-glass analogy, ISO could be described as the size of the glass. At a low ISO, the glass is a large one. At a higher ISO, the glass is smaller. In effect, if you are shooting with a high ISO, you need less water to fill the glass.

Equivalent exposures

Much like filling a glass with water, getting an exposure can be achieved quickly or slowly, but you'll get there in the end. You can use a trickle of water—so that would be a small aperture—for a very long time, and the glass will eventually be filled. Alternatively, you can open the tap all the way—the equivalent of a large aperture—very briefly, and the glass will be filled.

The same is true in photography. Two different exposure settings can result in the same amount of light being recorded inside the camera.

Sunset beer

Okay, it's a glass of beer. But that's much more fun than water.

How, then, do you put this into practice? It depends on what you want to achieve with your photo. If you're looking to secure a particular depth-of-field you'll set your aperture accordingly and then adjust the shutter speed and ISO to complete the exposure. For a long exposure shot you'll need to think about whether it needs a small or a large aperture and a low or a high sensitivity.

Drink up!

More unusual ways of looking at things and remembering rules are in my lovely book, The Rules of Photography and When to Break Them. Available in print from Amazon UK and US.

For those days when you need to be in several places at once: multiplicitous images

Multiplicity, or the art of creating images containing several yous, or anyone elses for that matter, isn’t a digital discovery. It’s something that people have been doing for decades: it's remarkably easy to achieve with film. You set up your shot and either you don’t wind on your film before re-exposing the frame with your subject positioned anew in the scene; or you wind on your film and then wind it back again in between shots. The important thing here is to slightly under-expose all of your shots in the sequence to ensure that your final image isn’t an over-exposed white mass. That might look like me, but actually it's my Ma

If you don't happen to have a Holga lying about (they're great for creating multiple exposures), you can do it with a digital camera, too. Depending on the camera you have, you've a few options for creating a multiplicitous image. Quite a few come with a multiple exposure setting now: you determine how many exposures you want to make and the camera will re-expose the same 'frame' in-camera and adjust your expose settings accordingly to ensure that you don't end up with a too-dark or too-light image. Marvellous... if you have a camera that can do that. If not, you'll need to make friends with Photoshop, or a Photoshop-esque editing package.

Before we go any further, it’s important to remind you that achieving a great final image relies on producing a good image in-camera first. It doesn’t matter how ginormous the barrage of editing you’re going to subject your photo to, it’s got to be good from the get-go. This is just the same for a multiplicity image as any other.

When you set out to create a multiplicitous image, your starting point is your concept. Think of the story that you're trying to tell and what you need to tell it. Having a clear plan makes it so much easier when you're shooting the images because—unless it's a distinct element of the story—you need consistency in your images: furniture can't move between shots, the light needs to be coming from the same direction, and you don't want to be flapping around.

When the scene's arranged, set your camera on a tripod, adjust it's exposure settings and focal point, and shoot a 'plate' image. This is a base photo, devoid of the story's characters, onto which you'll build your final creation.

Now you can shoot your series of images containing your subject in as many different positions as your composition merits. I've found it useful to go for more rather than fewer photos; it gives you more flexibility when you compile your final image.

[gallery ids="6703,6704,6705"]

When you've shot your images, import those you think you might want to use into Photoshop using the Load Files in Stacks option (File>Scripts>Load Files in Stack), which should import your images so that they are perfectly layered one on top of the other.

Importing made easy

Next apply a layer mask to each of the layers, barring the background image, which should be the ‘empty’ plate.

Using the eye icon on the Layers Palette, toggle off all of the layers from view except Layer 1. Now brush your subject, along with anything like indentations in the chair where she or he is sitting or shadows, out of the image. It's those small details which add credibility to the unbelievable, which is what makes them important to the final composition. And while it might seem counter-intuitive to brush your subject out of the image, it isn't really.

Brush out your subject - it makes sense, really

When you’ve disappeared your subject from the scene and you’re happy with the refinement of the edges, invert your selection by pressing Cmd+I on a Mac or Ctrl+I on a Windows machine. The subject will miraculously reappear and the superfluous background will disappear.

Do take care when you're areas where overlapping occurs, because it's here where your image will succeed or fail in its realism.

Repeat this process for each of the layers, toggling them on and off as necessary to decide on which placements you want to keep, and which you wish to discard. I’d recommend saving the image as a PSD file with all the layers intact, which will allow you to revisit it and re-edit as often as your Dr Jeckyll needs to meddle with your Mr Hyde.

Three wise monkeys? Or something like that

When you've settled on a final version, delete the layers that you don't want, save it as a PSD file, and then flatten it and export it as a JPEG image. Ta-dah!

Christmas is coming: zoom bursting!

The twinkling lights and glittering decorations of our Christmas tree are always far too good a photographic opportunity to pass up. Last year they were my testing ground for a Pentax X-5 that I had to review. This year, I decided to play around with zoom bursting, to make it appear as if the lights are bursting out of the image. While the abstract motion effect of a zoom burst might look as if it's a pain to achieve, it actually isn't that hard. You definitely need a zoom lens on your camera and preferably a tripod; then you just need a bit of patience to get it right.

Compose your frame and focus on your subject. It's actually one occasion when centre-focusing really does work and doesn't leave your composition feeling flat and dull. But of course, it's whatever works for your photo. You'll probably find it easiest to zoom in as close as you can and then lock your focus or set it manually.

In order to achieve the motion effect you'll need a slow shutter speed, so that you have sufficient time to turn the zoom ring on your lens. If you're not confident using full manual control, do flick your camera into Shutter Priority (S or Tv) mode. For this series of photos I experimented with exposure times ranging from one-and-half seconds to ten seconds. The optimal speed seemed to be five seconds, but of course it is going to to vary depending on your subject.

Christmas is coming

I kept the aperture fairly small and the ISO relatively low. Being a long exposure shot, there was a strong possibility that it would come out over-exposed if I adhered precisely to the camera's meter, so I under-exposed by a stop-and-half. If I'd been shooting in Shutter Priority mode, I would have achieved the same effect by applying exposure compensation.

When you're ready, depress your shutter button, or use a remote release to help avoid camera shake, and then steadily zoom out throughout the course of the exposure. If you'd like to ensure a little more definition for your subject, don't begin to move the zoom ring immediately, but let it rest for about a quarter of the exposure time and then start to move it.

In most cases, you will probably want to zoom out to give the impression of the subject bursting forth from the image. I also played around with zooming in and rather liked the effect. It's all going to depend on what works for your photo.

Once you have the basics down, it'll be a case of playing around to see what looks best. Have fun!