How To Use A Wide-Angle Lens
Here's my friend Heidi photographed at the spectacular Paradise Harbour in Antarctica. Heidi was a customer on a November 2010 Aurora Expeditions photography tour I co-ran with my friend and colleague David Burren.
After slugging my way to the top of the hill I had 2 remaining goals in mind. I wanted to photograph the spectacular landscape and I wanted to be able to create a lasting visual record for some of my new friends of their visit to this amazing location.
So, as well as some more formal portraits of folks, it was great to have the opportunity to photograph Heidi as she made her way down the slope in the best way possible. And let me tell you, it was a hoot and a whole lot easier than the track upwards. As I was one of the last up the hill perhaps it's time I thanked folks, by which I mean their derriere's, for making by own path back down nice and smooth.
How to Use a Wide Angle Lens
The trick to using a wide-angle lens is to first understand the potential compromises associated with wider focal lengths. Let's summarize, in my preferred language (i.e., simple speak), some essential aspects associated with wide angle lenses used on today's DSLR cameras.
- the shorter a lens's focal length (e.g., 24 mm as opposed to 200 mm) the wider the angle of view displayed within the camera's viewfinder/frame and, as a consequence, the more of the scene that's recorded
- the larger the camera's sensor the more of the scene (i.e., top, bottom, left and right) that's included within the frame
- the shorter the focal length the smaller and further away distant subjects (e.g., mountains) appear
- the shorter the focal length the larger and more dominate the near foreground becomes
So the lesson is, wherever possible, to include an important focal point (i.e., subject) in the near foreground whenever you're making photos with a wide angle lens. Move a few steps back and that subject appears significantly further away and, as a consequence, looses its importance.
As a case in point the above photo was made with a Canon 24-105mm f4 zoom lens, at 24mm, on a full frame Canon 5D Mark II camera. Back in the day a 24mm focal length was considered, by many, as a classic wide angle lens. That's no longer the case when that lens is used on most modern DSLR cameras.
Do You have the Right Camera for Landscape Photography?
These days most DSLR photographers use APS-C sensor cameras. The physically smaller nature of these sensors, when compared to full frame sensors or 35mm film-based cameras, changes the effective focal length of the lens attached. Most Nikon and Sony DSLR cameras have a sensor that's half the size of a full frame camera. That means you are effectively recording your image onto a much smaller canvas than would be the case with a full frame DSLR or 35mm film-based camera. As a consequence a significant amount of the surrounding scene (top, bottom, left and right), that would normally have been part of your composition when photographed with a full frame or 35mm film-based camera, is cropped out by the smaller APS-C sensor camera.
By the way most Canon DSLR cameras have a sensor that is slightly smaller again, albeit only by a tiny amount.
But the goddess of photography is not entirely cruel. In fact, while she gives with one hand, she takes with the other.
Oh Joy, It's Maths Time
To obtain the same framing, when standing in exactly the same place as I did to make the above photo with my full frame Canon 5D Mark II (or an equivalent full frame Nikon or Sony) camera, Nikon and Sony folks employing an APS-C sensor camera would have to use a 16mm focal length. That's 16mm x 1.5 to arrive at 24mm, a 50% increase in effective focal length.
As the cropping factor associated with Canon APS-C sensors is 1.6x a slightly wider lens would be required to achieve the equivalent 24mm focal length.
How Does this Effect You
As most lenses are still made with full frame and 35mm film-based cameras in mind the actual focal length of the lens, when attached to a common APS-C DSLR camera, is no longer relevant. What you need to be concerned with is the effective focal length that eventuates as a consequence of the in-camera cropping that occurs on all cameras incorporating APS-C sized sensors.
The reality is that most folks don't realize this is even happening because the image they see in their viewfinder closely matches the image that is recorded onto their camera's sensor. It's only when they compare camera views or final images, side by side, that this significant difference in coverage is evident. Just remember that a significant amount of the scene, that's projected through the lens, is being cropped (i.e., cut) from the image that's recorded onto an APS-C sensor.
How Do You Feel Now?
Now I'm sorry if, after reading the above explanation, you feel anxious, annoyed or down right disappointed. Please, don't be angry with me. I'm just the messenger. I didn't create the problem, but am working hard to help make sense of it for you. And remember, the goddess of photography deals out the cards equally. With an APS-C type camera you, potentially, both win and lose.
There's no doubt a large viewfinder image makes critical composition easier. It also makes it easier to see, in the case of a portrait, that your subject has a pleasing expression and/or open eyes prior to you tripping the shutter.
Yet Hope Remains While the Company is True
You do loose on the wide angle end with APS-C size sensors, however more and more lenses are being manufactured to help overcome this problem. Take the kit lens that comes with most APS-C DSLR and mirrorless cameras. Perhaps it's an 18-55mm focal length. Now that number refers to the lens's actual focal length, but you need to do the math (e.g., maths for folks from Australia and the UK) to determine its effective focal length on your camera. Let's stay with Nikon and Sony, as the math is easier.
The 1.5x cropping factor associated with your 18-55mm kit lens produces an effective focal length of 27mm to 82.5mm (approx). Now, what does that mean. Well, again, you lose on the wide angle end. What was a very wide angle lens actually produces an angle of view similar to that associated with a general purpose (i.e., 28mm) wide angle lens on your APS-C camera.
Now, before the tears flow, here's the good news. By cropping out a significant amount from the edges of the scene the APS-C sensor provides the impression that you're lens is, in the case of Nikon and Sony APS-C sensor cameras, 50% more powerful than it actually is. In this case the 55mm focal length gives the impression that you've photographed with a 82.5mm (and it's OK to round that off to 80, 82, 83 or even 85mm approx.) lens. So you see, while you lose on the wide angle side of the ledger, you definitely win on the telephoto end.
So there's no silliness regarding brands it's important to understand that with the slightly smaller Canon APS-C sensor you loose a little more on the wide-angle end and, therefore, win slightly more on the telephoto end of the scale than with its Nikon or Sony APS-C counterparts. But, as these differences are slight, I wouldn't be basing a camera purchase on the difference in size between APS-C sensors.
What Does This Mean To You?
If most of your photography is conducted with wide angle lenses (e.g., landscape and architecture) you're probably better suited with a full frame camera. If, on the other hand, you photograph predominantly sports, wildlife and candid portraiture you'd likely enjoy the benefits associated with the impression of increased magnification associated with a common APS-C sensor camera. Just remember, when employing an APS-C sensor camera, that the image projected through the lens is being cropped. There is no actual optical magnification associated with the smaller sensor cameras.
At the end of the day the camera that most folks buy is determined, at least in part, by budget. The sensor is, by far, the most expensive component of a DSLR camera. The smaller the sensor the cheaper the camera is likely to be. It's this fact that has seen a steady decline in the price of most modern DSLR cameras and, together with the other advantages associated with digital photography, has resulted in a proliferation of enthusiast photographers worldwide.
Just be aware that, if you're looking to specialize in one particular area of photography, your ability to make the images you want to can be adversely affected by the camera you purchase. Therefore, as part of your purchase decision, it's important to understand the benefits and potential compromises associated with APS-C and full frame cameras alike.
I have a major publication designed to help you with the purchase of a DSLR or mirrorless camera. It will be available, through this site, in the next few months.Stayed tuned!