Still got your camera on the auto white balance setting? Make the change to see your subject’s true colours – you won’t believe your eyes...

 When I first considered switching to using a DSLR camera for my professional work, some years ago now, I came across the term white balance and wondered what on earth it meant. It didn’t take me long to realise that white balance was something I’d been doing with my film photography for years; it was simply the terminology that had changed. In order to fully understand the purpose of white balance (WB) it’s necessary to know a little about the science of light. Human beings can see only a fraction of the light waves that exist, which we refer to as visible light. (Others, such as Ultra Violet and Infra Red are invisible to humans but may be detected by certain cameras and photo sensitive materials.) Because of the way our brains work we see all visible light as a neutral white, irrespective of its source or colour temperature. For example, look at the light from a household light bulb compared to sunlight: both light sources appear to have the same ‘colour’ – white. However, this is only because our brain uses a biological white balance control to make all light appear as neutral white. In reality, that’s not the case. Depending on the source and external factors such as weather, time of day and the season, the colour temperature of light varies. If these variances aren’t compensated for, then colour casts may affect your images.

Continuing his series of articles looking at taking control of your DSLR camera, Chris Weston explains the role of digital ISO and its relationship to noise

Anyone who was involved in photography in the period BC – that is, before computers – will be familiar with the acronym ISO. The letters stand for International Standards Organisation – the world body governing all international standards - and refer, in this case, to a standard measurement of the sensitivity to light of photographic film. For example, we have two Fuji Provia films, one rated at ISO 100 and another at ISO 400. The latter is four times as sensitive to light as the former.

In digital photography we use the same acronym and numbering system (ISO 100, ISO 200, ISO 400, etc.) in relation to the photo sensor. However, unlike film, here ISO relates to amplification rather than sensitivity. For example, when set to ISO 400 the light signals that are detected by the sensor are amplified twice as much as when ISO is set to 200.
In a nutshell that’s the difference between the two media in relation to light. Film is more or less sensitive depending on the size of the silver halide crystals used in its manufacture, whereas the common sizes of the photo detectors in a digital sensor remain fixed but the light signal is increased (amplified) with each upward increment in ISO rating. Fortunately for photographers, and to make life easy, the terms have been kept consistent to the extent that they are, to all intents and purposes, interchangeable.

Take Control is a series on getting to know your DSLR that appeared in some of the first issues of DSLR User magazine – designed to help people stop using the Program mode, the series was incredibly popular and was eventually produced as a booklet on its own. Now, for the first time, all the sections are available online – kicking off with this first installment that focuses on Exposure...

Introduction

We are all aware of the increasing level of sophistication of modern cameras. Indeed, a Digital SLR camera is effectively a fully functional computer, complete with a processor, RAM, semi-permanent storage, a monitor and even a rudimentary keyboard. All of this technology has, in many ways, made photography easier. Programmed auto-exposure (AE), auto-focus (AF), auto-white balance (AWB), auto-bracketing and auto-processing (as used in JPEG mode), to name but a few, have left the photographer little to do other than press the shutter. Or have they? 

Of course, the problem with all these automatic functions is that it is the camera and not the photographer that is making all the decisions. And the problem with this scenario is that the camera has no idea what it’s doing artistically. It is merely following a set of instructions programmed in a laboratory. Sure it can give you a technically perfect exposure based on a set of averages but the problem with averages is that they lead to average photographs.

So do you want to be an average photographer or do you want to mix with the best? Because competing with the best means doing what they do. It means eschewing all those pre-programmed functions and taking control of the camera. That’s what this new series of regular features is all about: teaching you how to use the technology in your camera to create the images you want.

In a sentence it’s about making pictures as opposed to taking them, so that next time someone says, “That’s a great photo, you must have a really expensive camera” you can reply “Sure. And Monet owned some really expensive brushes”.