Telephoto lenses

Having spent a great deal of money on a big telephoto lens it makes sense to get as much use out of it as possible, writes Guy Edwardes.

But how many of us bother to put up with its weight and bulk when out shooting landscapes? We should, as it can be very effective at providing a unique perspective, especially when working in much-photographed locations!

Focal length
Lenses up to 200mm are quite commonly used for landscape photography, so here we are dealing with telephotos of 300mm and more. I frequently use my 600mm lens for landscape photography, often combined with a 1.4X or even a 2X extender. When I’m using the 7DmkII that’s the equivalent of a 1344mm lens, delivering roughly 27X magnification! With such a narrow field of view these lenses are great for picking out and isolating distant details within the wider landscape. These scenes often go unnoticed by the naked eye as they form such a tiny part of the landscape as we see it.

Composition
Landscape photographers need to learn to “see” like their lenses, in all the different focal lengths, in order to find interesting and effective compositions. Training your eye to see like the long telephoto lens is perhaps the most difficult. Because of this it can be useful to use a pair of binoculars to help spot potential compositions way off in the distance. When shooting with long lenses you need to search for simple uncluttered compositions. Patterns within the landscape such as intersecting dry-stone walls, hedgerows and meandering rivers can all work well. It is still useful to have a focal point if possible, but a good pattern can sometimes be strong enough on its own. Long lenses are particularly useful for shooting layers of receding hills or mountain ridges, especially in misty or hazy conditions when the effect of recession is amplified.

Depth of field
You might think that as telephoto lenses exhibit shallow depth of field you might need to use a small aperture when shooting landscapes, but this is not always the case. Ok, if your scene includes elements that are both distant and considerably closer you’ll obviously need to stop well down if you want them both to be sharp, but in many cases everything in the scene will be distant, in which case a relatively wide aperture can often deliver sufficient overall sharpness. I often find myself using a telephoto lens whilst shooting from a high vantage point picking out details in the valley below. In this case a middle aperture of f5.6 or f8 is often sufficient to capture the whole scene sharply. This also has the benefit of allowing you to use a faster shutter speed to combat vibrations.

Ensuring sharp images
Now for the tricky bit! If you thought it was hard to make sharp images of wildlife with the big telephoto lens you could be in for a shock … with landscapes it can be even more difficult! The problem is two-fold. Firstly you have the physical mass of the lens combined with the magnification. This means that the slightest breath of air can make the whole set-up vibrate like a tuning fork. The solution to this is to create the most stable support possible, which is not necessarily a tripod. The best way to support a big telephoto lens when shooting landscapes is to place one beanbag under the camera body and a second one under the lens hood. The beanbags must be filled with something substantial like rice, corn, birdseed or polypropylene balls (not lightweight polystyrene). This provides a really stable support without restricting the focussing ring. However, this only works where you have somewhere to set up two beanbags, such as a wall, gatepost or car roof. At other times you may have no option but to use a tripod. In this case use the sturdiest tripod you can get your hands on, preferably a video style tripod with twin-tube legs, as they are designed to minimise the effects of the wind-induced torsional vibration – which is the bane of long lens landscape photography. If all else fails it’s simply a matter of supporting the lens as best you can and using the fastest shutter speed possible, perhaps in combination with Image Stabilisation or Vibration Reduction (which should be set to Mode 1 or Normal). Resting your arm across the top of the lens will also help to dampen some vibrations.

Atmospheric conditions
As if that wasn’t enough, the second issue with long lens landscape photography tends to be the atmospheric conditions. A phenomenon know as “atmospheric shimmer” or “atmospheric refraction” disrupts the speed at which light passes through the atmosphere, making objects appear rippled or un-sharp. Viewing these objects through a high magnification lens makes the effect all the more apparent and can make the resulting images look soft and distorted. The effect tends to be at its worst on hot sunny days in the middle of the day, but it can occur at any time of the day or time of the year. Thankfully, as landscape photography tends to be done early and late in the day when the light is more favourable, the effects of atmospheric shimmer are often minimal. However, there will be occasions when the atmospheric conditions won’t allow you to use a long lens and there will be no option but to return another day.

So, using a long telephoto lens for landscape photography can be very challenging, but in my opinion the resulting images are usually well worth the effort!