Remember that wedding you went to recently? Everyone was dressed up and looking great, with the photographer snapping away at the frightened bunnies happy couple, and you wondered about the camera. Okay, maybe it wasn’t a wedding; perhaps it was a cricket match, rock concert or surfing competition. All (or at least most) of the photographers you see at these events have large cameras and even larger lenses. The cameras are not just big because they offer more complex and daunting shooting controls, but also because they are what we call “Full Frame” (or “FF”)
Full frame cameras (Such as the Canon EOS 1Dx and 5D Mark III or the Nikon D800 and D3) have sensors which measure 24mm x 36mm. For those playing at home, this is the same size as (35mm) film. Most other DSLR cameras at the entry and consumer levels have what we call a “cropped” sensor, meaning that their sensors are smaller than their Full Frame counterparts.
Cropped sensors have their plus points; the cameras are smaller and lighter, the lenses too are smaller and lighter and able to cover plenty of zoom distance. The other great thing about crop sensors is that if you put a lens designed for Full Frame on them you actually get more zoom from the lens. Because the sensor is smaller, you are essentially cropping out the edges of what the lens can see, and as such get closer to your subject with clarity. The easiest way is to calculate what your equivalent millimetres would be is to take the focal length and multiply it by 1.5 (or 1.6 if you are a Canon user). The drawback is, of course, that you don’t get nearly as wide at the back end of your zoom range. For example if you want to use my favourite lens, the 24-70 f2.8, on a cropped sensor it is really closer to 35-105mm. This is great if you want to photograph wildlife, not so wonderful if you are in to landscapes.
So, why do people choose to shoot Full Frame? Primarily it is the image quality. Those who have spent any time in a darkroom know that the more you try to enlarge an image the more detail you lose, but this is lessened if you use a larger negative to begin with. This basic physics principle still applies when working with a digital sensor; a larger sensor provides a greater area for the light to fall on and as such offers more detail. The larger sensor also produces less grain in low light situations, meaning you can shoot on a much higher ISO and still retain clarity in your shot. Say, for example, you have two cameras which boast 14 Megapixels. One with the cropped sensor has all of the pixels grouped together, whereas the full frame has larger pixels which are spread apart, providing a cleaner image. This means that if you were taking photos in low light and require a higher ISO (as in, for your sensor to be more sensitive) you get better results than if you were to use the same ISO on a cropped sensor. In short, larger sensor=less noise (in general. As with all rules, there are the occasional exceptions).
Full Frame cameras also offer a wider focal length, which is perfect for shooting landscapes and architecture. Remember, full frame also provides finer detail which can be crucial to architectural work. A Full Frame camera can also be extremely advantageous to those wanting to shoot with available light as again, you have a wider range of ISO options.
Until the end of 2012 many people considered FF cameras to be too expensive and too complicated for general use, despite the benefits. That was until Nikon and Canon brought out their new DSLR cameras; the D800 and 6D. These are FF cameras designed with all of the image quality benefits the large sensor brings, but in a smaller body with easier controls and even some Automatic features. In short, they are professional camera quality in an enthusiast body. They do still require the lenses designed for full frame, and yes some of these lenses are huge. But not all of them are, especially if you take a look at Prime lenses such as a 35mm or 50mm.
In sum, the line between professional cameras and consumer cameras is becoming more indistinct - you don’t need to have a full-on professional camera to take exceptional images. Of course, training and practice is paramount (the most important part of the camera, after all, is the photographer), but professional technology is now more easily available to more people in a user-friendly format. The best thing to do is always keep reading, keep practicing, keep taking pictures and learning what you need to use to achieve the effect you want. But most importantly, keep taking pictures.