Photographs can tell a whole story that we reporters need hundreds of words to explain. A single frame can capture the pinnacle of an emotion and one of the best examples of this is a shot known as The Falling Soldier by revered photojournalist Robert Capa.

The iconic image, of a Spanish Republican militiaman being shot for his cause right in front of the lens, is just one of more than 150 stills from six different conflicts that form This Is War! Robert Capa At Work, the core of a three-stranded exhibition at east London's Barbican Centre.

Capa was, in fact, was a Hungarian named André Friedman who worked during the first half of the 20th Century and who adopted the Westernised moniker as a way to better market his photographs.

Possibly fatigued by today's ubiquitous colour paparazzi pictures, I found his black and white images captured startling clarity, texture and depth, whether it be the scree on which Spanish Republican soldiers are poised, the smoke rising from an artillery explosion, or the blood spreading across the floor from the still-warm body of an American machinegunner shot dead moments earlier.

The way Capa framed and lit his subjects is a compelling feature of his work and in many photographs, whether by sheer luck or ponderous consideration, he seems to have struck the perfect, and often bleak or upsetting, balance.

That said, sometimes just being on the spot to take a particular photograph is what counts, and this aspect of the craft is apparent in Capa's famously blurred Second World War series documenting the DDay assault.

In an age where images are digital and disposable and anyone with a mobile phone can be a photographer, being able to study the original prints, and resultant magazine spreads, meant I could appreciate the real hands-on work involved in publishing a photograph at this time: having to think about each shot (so as not to waste film), taking the picture and sending home the rolls of film in order to have the picture desk develop them, crop them (by hand) and set them on to the page.

This Is War! not only pays testament to the legendary lensman's commitment - sticking it out to the last to get THE shot - but shows that aside from peering avidly through his viewfinder, Capa was a highly receptive stickler for detail who provided his paymasters with lengthy, precise captions from the front line.

The other two sections in the triple-header exhibition are Gerda Taro: A Retrospective, which showcases photographs taken by Capa's lover and collaborator, German-born Gerda Taro, and On The Subject Of War, comprising displays of images, documentaries and video installations from four contemporary artists exploring the impact of the wars in Iraq and Afghanistan.

Overall, this hugely interesting exhibition is a fascinating way to learn about Robert Capa, a celebrated and progressive photographer who you may have never heard of but whose work you at some time have probably seen and admired.

**This Is War! Robert Capa At Work, Gerda Taro: A Retrospective and On The Subject Of War run side-by-side at the Barbican Art Gallery at the Barbican Centre, east London, until January 25 2009. Tickets £8/£6 concs and advanced bookings. The gallery is open daily from 11am, closing at 8pm on Sat, Sun, Mon & Fri, 6pm Tues/Wed and 10pm Thurs.