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I thought I knew a lot about photography, but I was completely taken by surprise when some photographers started talking about pancake lenses. What is a pancake lens? Jessica, Jeju Island.

Photographers are strange people. Sometimes photographers like big lenses, sometimes they like the smallest possible lenses. The smallest lenses available are commonly called pancake lenses because they’re flat, like a pancake.

For quite a while, pancake lenses had fallen out of favour in photographic circles. A little while ago Olympus released a pancake lens for its new DSLR cameras. That kicked off a surge in renewed interest in pancake type lenses.

Why are they so popular? Well, the biggest reason is that they’re small. One benefit of their size is that the lenses are light and easy to carry. However the biggest benefit is that the small, flat lens makes the camera much more discrete.

Pancake lenses are popular amongst street photographers for this very reason. A long lens is quite obtrusive. Pointing it at someone can attract their attention or make them aware of the camera. Since photographers want to capture people in natural situations, a big lens is too noticeable. A pancake lens makes the camera appear much smaller and less obvious. It allows a photographer to remain unnoticed while taking photos of people.

Pancake lenses are usually short range prime lenses. Most pancakes are between 35 and 50mm in length and around f1.8 to f2.8 maximum aperture. These apertures are important and one of the biggest benefits of prime lenses - because it means the lens is fast and sharp.

Often, pancake lenses will be manual focus, due to their small size - autofocus pancakes are rare indeed.

The other important aspect is image quality. Short prime lenses are a playground for bokeh; out of focus area. Bokeh is important to photographers because it determines the aesthetics of any area beyond the camera’s depth of field settings. If a lens is poorly designed, it will not render out of focus areas very well. The bokeh will look harsh and flat. A good prime lens will produce great bokeh, much better than most zoom lenses.

The resurgence in popularity has resulted in a number of companies developing pancake lenses. Nikon and Canon both have new pancake lenses hitting the market. Panasonic and Olympus have already released lenses with various mounts. There are also a number of third party lens makers who have pancakes; the two most popular being Zeiss and Voigtlander.

The only real downside to pancake lenses is their price. Usually, a pancake will be two or three times the price of a similar standard prime lens. The higher cost is due to the engineering required to make the technology work in a ‘flat’ lens.

With photography’s recent surge in popularity, camera makers have been outdoing each other to make newer and better equipment. This will probably result in companies also developing many more lens types. Nikon have already released tilt shift lenses to appeal to architect photographers. It’s likely that there will be more pancake lenses on the market in the next few years.

For now, it’s probably not worth owning a pancake lens, unless you want to practice your manual focusing. Save your money and invest in some good standard prime lenses, such as a 50mm f1.8.

Happy shooting!

David Smeaton

I’m having a lot of difficulty understanding depth of field. Can you explain it more clearly? Peter, Seoul.

Depth of field (DoF) is difficult to explain without diagrams and charts. It’s more about math and physics than it is about photography. However, I can give you some starting information, which is enough for most photographers.

DoF, simply, is the distance between the nearest and farthest objects which appear to be in focus. This is quite a subjective concept, because it’s difficult to always define the focal range. Further, all photographers have different views regarding the use of DoF.

However, DoF is extremely important to photography and film.

Focal range is controlled by the camera’s aperture. A small aperture (eg f22) will have a very wide depth of field. A small DoF will result in large elements of the photograph appearing in focus. Conversely, a wide aperture (f2.8) will have a much smaller depth of field. As a result, the out of focus area will be quite big. Yes, it’s ironic that these concepts seem inverse (small aperture - wide DoF, wide aperture - small DoF).

When it comes to understanding what parts of the photo will be in focus, there’s a two thirds rule applied to DoF. One third of the area in front of the focal point will be in focus, but two thirds of the area behind the focal area will appear to be in focus. So it’s important to know that much more of the focal range is behind the focal point, not in front. It’s not evenly split (50/50) around the focal point.

There are a few other factors which can make the focal range either larger or smaller.

Firstly, as stated, small apertures give wider DoF.

Second, shorter lenses also create a wider DoF. A 50mm lens will give a much wider DoF than a 200mm lens, if the same aperture and settings are used.

Finally, the greater the shooting distance, the greater the depth of field. This one is logical really. If photographing mountains, DoF can be read in kilometers. If photographing bugs (macro photography) DoF is mere milimeters. So the further away your subject, the longer the DoF.

Generally, photographers have two approaches to controlling DoF. In most cases, photographers prefer short DoF and large areas which are out of focus. This helps control the viewer’s attention by blurring the foreground and background elements, while keeping the subject in perfect focus. Portrait photography is a good example of this. Most portrait photographers use longer lenses and wide apertures.

Small DoF also creates more ‘bokeh’ which is one of photography’s most important attributes.

However, there are many times when a wide DoF is desirable, such as in landscape photography. A good landscape photo should appear to have everything in focus, from mountains at the back to rocks in the foreground. This can be achieved with wide lenses, small apertures and focusing to infinity (which all cameras can do).

Those are the basics to depth of field. The important thing to remember is that DoF is easy to control because the aperture, lens length and focal length all play a simple part. Combine them well and you can be a master of controling DoF, producing great photos with very high impact.

Happy shooting!

David Smeaton

I’ve heard a lot of people talking about prime lenses, but I’m not really sure what they are. Are prime lenses better than other kinds of lenses? Mitch, Pusan.

There are two types of lens, primes and zoom lenses. Zoom lenses have a minimum and maximum focal distance and you can zoom between those distances. For example, a zoom lens might be 18mm - 70mm. Therefore the lens can capture any focal length between 18-70mm. This is very convenient for photographers, because you can get close to your subject without having to stand too near. Sometimes it’s impossible to walk right up to your subject. A zoom will help get closer to the action.

Zoom lenses cover various ranges. 12mm - 24mm would be considered a wide angle zoom. 70mm - 200mm would be considered a telephoto zoom. So the type of zoom is defined its range.

Prime lenses are much more simple. Prime lenses have a fixed focal length. So there’s no zoom in the lens. The only way to zoom is with your feet! For example, a common focal length is 50mm.

While it may seem that primes are far less useful than zooms, both types of lens have their advantages. So many photographers keep a combination of primes and zooms in their camera bag.

Thanks to the laws of physics and the wonders of engineering, primes have a few benefits that make them worth using. The first benefit is that prime lenses are often lighter than zooms, because they require less glass and mechanics inside. For the same reason, primes are usually cheaper.

However there are two more important reasons to consider using primes. The biggest reason is that prime lenses have wider apertures. Most zooms (the expensive ones) have a maximum aperture of f2.8. However, it’s easy to buy a prime lens with f1.2, f1.4 or f1.8.

Actually, the 50mm f1.8 lens is one of the most popular lenses that photogrpahers buy. This lens is very sharp and fast. It works well in low light situations and creates wonderful ‘bokeh’ by exploiting the shallow depth of field that results from using wide apertures.

Prime lenses tend to take higher quality photos than zooms. The trade off with zoom lenses is the engineering compromises picture sharpness. Primes are much sharper. Zooms tend to also be less good at bokeh and blurring the out of focus areas. This is also something primes do well.

However, these days zoom lenses are almost on par with primes in both bokeh and sharpness.

It’s worth using both types of lenses, because they give different benefits. Most photographers use a zoom as their base lens (for walking around) and switch lenses for shooting different purposes. I have one prime lens in my kit, a 50mm f1.8, but I’ve chosen to use zooms because as a traveler I need to get more range with fewer lenses.

But every photographer should definitely have one fast sub-f2 prime lens in their kit. It’s a great investment and it usually becomes the photographer’s favourite lens.

Happy shooting!

David Smeaton