Basic photography – manual settings in a nutshell.

If you are content to point and shoot with an automatic camera, you will these days usually do just fine. But let’s say you are looking for a bit more, with some manual control over the settings. That’s where most amateur snappers tend to take fright. They think it’s all a bit technical. Actually, it’s not. It’s all essentially about ‘exposure’, which is basically the brightness or darkness of a photo, and this comes down to three settings – aperture, shutter speed and ISO.

The aperture is simply a set of blades which widen and narrow to control how much light enters the camera. Aperture sizes are measured by f-stops, with a high f-stop (say f/18 or f/22) corresponding to the aperture being quite small (less light entering the camera), and a low f-stop (say f/3.5 or f/5.6) meaning that the aperture is bigger (more light). The aperture also controls what is known as the depth of field, which is an indication of how much of the picture is sharp and how much is blurry. So if you want a figure in the foreground to be sharp and the background blurry, you would want a shallow depth of field (low f-stop, wide aperture). If you want the entire field sharp (for example, a mountain range) you are looking for a high f-stop (small aperture). In summary, a wide aperture (low f-stop, say f/5.6) gives you a brighter photo but a shallower depth-of-field, while a small aperture (high f-stop, say f/18) gives you a darker picture but more depth of field.

The shutter speed is simply a measure of how long the shutter is open, so a slow shutter speed (say 1/60 of a second) allows time for more light to enter, producing a brighter picture (but more blur if objects are in motion), and a fast shutter speed (say 1/800 of a second) produces a darker picture but less blur. In summary, a fast shutter speed (say 1/1000) produces a darker picture, but will be susceptible to less blur, while a slow shutter speed (say 1/80) produces a brighter picture but is susceptible to more blur.

The ISO controls the exposure a different way, thrugh software in the camera that makes it extra sensitive to light. In particular, a high ISO (say 1600) will produce a brighter picture than a low ISO (say 200). A high ISO is consistent with more digital noise in the picture, however, which tends to make the photo look a bit more grainy. In summary, you would select a higher ISO for a brighter photo, but that opens you up to a ‘noisier’ (more grainy) picture, while a lower ISO will give you a darker (but less grainy) picture.

The art now is in combining these settings to give the best overall effect. For example, say you want to take a photo with some movement in it, so you decide to select a fast shutter speed (say 1/800). But the picture comes out darker than you’d like as a result. So you try to compensate by opening up the aperture (to say f/3.5), although this reduces the depth-of-field, blurring the background. Still, the blur doesn’t concern you too much as it’s what’s in the foreground that is the subject of the picture. It’s still a bit darker than you’d ideally like, though. Finally, you turn to the ISO setting and increase that to brighten the picture, while being careful to balance this with your desire to avoid too much digital noise.

By manually and independently setting the aperture, the shutter speed and the ISO, you now have the picture pretty much as close as possible to how you wish it to come out. The automatic mode will often do a good enough job, but using the manual settings allows you to have that bit more control over the final product. You can also use ‘aperture priority’ mode, where you set the aperture and the camera automatically sets the shutter speed. Or else use ‘shutter priority’ mode, where you set the shutter speed and the camera sorts out the f-stop.

That’s photography using manual settings in a nutshell. I hope it’s been of some help.