We all know about Photoshop and the dissimulation of truth. A picture taken recently of an armed Syrian fighter with a rifle in his hand contained an unexplained video-camera in the bottom left hand corner. So the photographer, in the interests of clarity, deleted the intruding camera in favour of some grainy trench wall.

The AP — quite rightly, as the offending photographer agreed – told the man it would no longer accept his work. Back in 2006, a Reuters picture of Beirut ruins after an Israeli air raid included some whisps of smoke ‘added in’ by the Lebanese photographer. He was told his work was henceforth banished by Reuters, which then typically refused to discuss the matter.

But for years now, a far more insidious practice has crept into the world of both newspaper and television journalism: ‘generic’ pictures of war which do not actually show what the reader or viewer believes he or she is looking at. The pictures are real enough. They haven’t been doctored or ‘touched up’. But they do not historically belong in the context in which they appear.

More than three decades ago, I noticed in a London paper an Imperial War Museum photograph of Royal Navy escorts fighting off U-boat attacks on an Allied convoy travelling from the US to Britain during the Battle of the Atlantic in the Second World War. Yet only a few months later, precisely the same picture appeared with a caption telling me that the warships were protecting an Allied convoy – carrying arms to Stalin’s Russia - on the perilous Arctic route to Murmansk.

No harm was done, you may say. The warships were British, the convoy was Allied, the North Atlantic only a thousand miles or so from the Arctic. But the historical moment – and I believe that the ocean in the picture was actually the Atlantic – was lost. Those warships and their convoy were real. So were the unseen men risking their lives aboard. But their heroism was reshaped by newspaper sub-editors, who decided that these seamen and their vessels should be moved to a different theatre of war – in order to better illustrate a story. The picture was not invented or photoshopped. It was real.

The same can be said of the wonderful Great War series by Colonel Jeremy Paxman – General Paxman’s diminutive rank of ‘Colonel’ was insultingly given him by the Radio Times – which has just begun on the BBC. In 1914, Paxman tells viewers, British, French and German troops became locked into miserable trench warfare. There were stunning shots in the first film of the series depicting the retreat of the British Expeditionary Force from Mons, and their subsequent stalemate in the trenches. But then two clips of footage showed British soldiers – in the context of the year 1914 – wearing steel helmets. And as any World War One buff knows – General Paxman included – steel helmets were not issued to British Tommies until 1915. Indeed, they were not worn in any great numbers by British troops in France until 1916.

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Again, no great problem. A British soldier in a trench in 1914 suffered pretty much the same as his successors in the same waterlogged ditches in 1915 and 1916. But yet again, the direct contact with those real soldiers we saw had been lost. Men who may have been killed in the 1914 trenches were represented by still-living soldiers in 1916. The pictures were, after all, ‘generic’. Does this matter?

Let me explain why it does. Some 20 years ago, I made a series of documentaries on the Middle East under the title From Beirut to Bosnia. During the course of our filming, we shot footage of Palestinian youths throwing stones at Israeli soldiers in the Gaza Strip in protest at the destruction of dozens of homes by Israeli forces. Some hours later, I was watching a news report on CNN on the return of the Palestinian delegation from fruitless peace talks with the Israelis. In this same report, the very same Palestinians – I recognized them individually – were seen throwing the same stones. But the report said they were ‘protesting’ at the peace talks. They were not, of course. But when I asked the CNN Bureau Chief in Jerusalem to explain the pictures, he said that Palestinians disapproved of the way the talks were going and that the pictures of the protestors were ‘generic’.

The implication, of course, was that the Palestinians usually protested, and protested with stones; indeed, that Palestinians were generically violent people. Yes, Palestinians did throw stones at Israeli soldiers. And these Palestinians were throwing stones at Israeli soldiers. But they weren’t throwing stones at them for the reasons stated in the report. ‘Generic’ footage was being used to illustrate a story that did not even touch on the reasons for the violence we were actually watching on the screen.

Feature films often use clips of documentary footage out of historical context. The movie Pearl Harbour, for example, includes real film of Luftwaffe aircraft bombing London during the Battle of Britain – but the movie scene in which the footage is used is set in 1941, the year after the battle ended. And gun-camera footage taken from RAF fighters in the Battle of Britain have been used out of context in any number of feature films.

But the practice of using so much film as generic – and thus as ‘wallpaper’ rather than illustrative of specific events — is growing more widespread. It worries me. It dishonours the dead and the survivors. One day, Stalingrad can be transposed for Kursk, or Alamein transposed for Tobruk. I fear they already are. What next? Beirut for Baghdad? Hama for Kabul? Anyway, aren’t those Muslims always fighting each other?

Irish put the word out on unwanted phrases

I shall mention, for the last time this year, The Irish Times – the best “Times”, by the way, on either side of the Atlantic.

Readers, all after my own heart, have been invited to contribute “phrases we could live without” to the paper’s letters page.

A few choice examples: “fulsome” (as in “fulsome applause”, “fulsome breakfast”); “power outages” instead of “blackouts”; “stand out” instead of “outstanding”; “as and from” rather than “as from”; “valued customer”; “have a pleasant and comfortable journey” and “as I see it”.

But they keep coming: “in living memory” – a close relative of “since records began” – and “has all the hallmarks” (of al-Qa’ida, usually, although hallmarks are meant to be a sign of value), “team player”, “am I alone in thinking” and “your call is important to us”.

I would add a few more of my own: “major player”, “ballpark figure” (almost always used by people who know nothing about American baseball), “guesstimate” and “war clouds were gathering” (in an article which always concludes with “the guns fell silent”).

Stop press. This weekend’s catch in that venerable Dublin newspaper includes “window of opportunity” and “not thought to be life threatening”.

My favourite is straight from the local Irish headlines: “Loose cows on the road”.