So let's come back to your dream “money no object” photographic system and contemplate the dilemmas and conundrums that rear up when we consider choosing and using long focal length lenses.

In Part 1 we looked at medium focal lengths and found difficult compromises to be considered between size, weight, portability, speed, performance, zoom range, cost and durability.

Tough decisions had to be made. And now considering the heavy artillery those choices get tougher as all the factors we considered previously become more extreme.

We need to get back to basics; why do we use long lenses? Simple; to fill the frame with distant subjects, catch action, and for the perspective effects of a narrow viewing angle. For sports and wildlife photographers super long lenses are vital tools of the job. For the rest of us it's not quite so clear-cut.

A misty dawn in the Blackmore Vale from Bulbarrow Hill, near Okeford Fitzpaine, Dorset, England. Canada. Canon 1Ds mkIII, 70-200mm f2.8 IS L lens @150mm, 1/5 sec @ f16, ISO 100

When I purchased my first SLR, an Olympus OM10, life changed and photography became an obsession that shows no sign of dissipating some 30 years later. Immediately I wanted to expand my system and the first and foremost desire was to obtain a telephoto lens; and the longer the better. In my inexperience I just assumed that was the way to go. I and I suspect most of us in our fledgling photographic days were seduced by the notion of “beaming in”. I thought I could watch from the fringes of life and make stunning shuts by simply bolting on a Big Long Lens and adopting a distinctly dodgy voyeuristic approach.

Of course I soon learnt; great pictures come about by getting stuck in, kneeling down amongst the rotting vegetables and immersing yourself in the situation, be it a bustling market in Yunnan or tranquil morning in Dorset. Reality dawned; in most cases a medium focal length lens is much more useful than an extreme one. And the notion of being a fly on the wall was soon dispelled; it doesn't matter how long a lens you've got, those peasants in Lijiang will know you're there.

There's no getting round it, you've got to take the occasional flak and get in amongst the action, making pictures come to you. Excess equipment, especially long lenses can get in the way; in the market in at Wasel a 300mm f2.8 lens will be more of a hindrance then a help. In amongst the prawns and sharp elbows a neat fast nimble 100mm is just the job for tight shots of faces, hands, simmering noodles and shiny fish. It's also a focal length that's a staple for landscapes, portraits, details; virtually all forms of photography really. So let's start by looking at medium telephotos.

The market at Wasel, near Lijiang, Yunnan, China. Nikon F5, 70-200mm lens

Straight away the zoom vs prime and speed vs portability debates rear their heads again. Take for example one endlessly useful zoom lens I'd never be without; the 70-200mm. I think with a modest 3x zoom range the optical performance is inseparable in the real world from prime lenses right through from 70mm to long. I use Canon's f2.8 L lens that has image stabilisation, excellent crispness and a price tag to match, but in this focal range there are many alternatives from all the major manufacturers and independents; you're spoilt for choice.

As with Nikon's similar offering it is a fast workable versatile tool, a mainstay of most pros. With lens hood fitted it's a fair lump though, and if size and portability are your key criteria a slower optic may answer well. Backpackers and landscapers who don't need fast apertures may well be tempted by an f4 variant, which is much smaller, lighter and cheaper. Working off a tripod the fast aperture and image stabilisation become redundant, so why not?

Trouble is most of us are opportunists; the hunter-gatherers of the photographic world, and a lens in this range is by definition a general-purpose tool. We may think of ourselves as predominately landscapers, macro types or whatever, but who's going to turn down the opportunity of an impromptu travel portrait, hand held in the fading light? There is no doubt an f2.8 lens with IS/VR is a more flexible tool then a slower one without the whirling internal motors. But it's less portable and more expensive. So we're back to square one again.

A local in the market at Tarabuco, Bolivia. Canon 5D mkII, 70-200mm f2.8 IS L lens @150mm, 1/250 sec @ f2.8, ISO 500

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