Bayswater Power Station, Bayswater, NSW. Please note that it is NOT smoke coming out of the stacks, it is steam.

"Please note that it is NOT smoke coming out of the stacks, it is steam" ... Bayswater Power Station in NSW. Photo: Jonathan Carroll

Where there's smoke, there's fire in the bellies of readers. Several times in past months the Herald has used photographs of steam rising from power station chimneys with captions or subheads intimating that the steam was a polluting pall.

The most recent example was on the cover of BusinessDay on April 17. The photo, taken at Bayswater power station in July last year, shows funnels of dark steam silhouetted against white clouds and a blue sky. It is an arresting image, so much so that several readers suggested it had been manipulated. A subhead was placed on it which said ''Up in smoke''. One picture, three words, dozens of complaints.

An example: ''This is clearly a digitally enhanced photograph but, because it focuses on smoke, it has nothing whatever to do with the story below it, which is about government policy regarding global warming, which relates to greenhouse gases such as carbon dioxide, not smoke. Worse, there is no smoke in this photograph. If there was going to be smoke, it would come from the two narrow chimneys in the centre of the photograph. What is inferred to be smoke is actually steam, coming from the two cooling towers on either side of the chimneys.''

Another reader suggested it had been shot at sunset ''when everyone knows that objects become blacker and more two-dimensional''. And another, who described the image and subhead as ''an egregious deception'', added: ''An old trick, been done many times before, and hardly appropriate for a serious section of a serious newspaper.''

First, the photographer did not manipulate the image in any way. He says he shot a series of four in the middle of the day using F22, which means a small aperture made the images razor sharp. And the reason he stopped to take the pics on the way to another job was because the scene looked so unusual. He presumes the darkness of the vapour was because it was heavy with moisture.

Second, and for me the most galling, is that the photographer had clearly written in his attached caption: ''Please note that it is NOT smoke coming out of the stacks, it is steam.''

Many readers feel the Herald and The Sun-Herald do not publish enough alternative opinions and stories on climate change and global warming, that they have formed an opinion and will stick with it. If you read the Herald's editorials, there appears little doubt that it has accepted the scientific consensus on the effects of carbon pollution on climate: there has been a gradual warming of the planet. The Sun-Herald leans that way, too. So when those who question the climate-change science see what they consider examples of the ''old trick'' referred to by the reader, they feel their concerns are justified.

The decision to use the image with such a misleading subhead was a poor one, and one which drew a message from the editor to ensure it did not recur. Although it was not the first time it has happened, hopefully it will be the last.

On a related matter, the Herald's decision on April 18 to publish without a warning the Pulitzer prize-winning shot of a shocked young girl standing amid bodies after explosions at a Shiite shrine in Kabul in December last year disturbed several readers. From one: ''I know it can be argued we should see this, that we must see this, in order to understand the nature of this brutality. However, many people, and particularly people with a history of post-traumatic stress, could be traumatised by this picture. Ultimately, I believe we must have a choice about whether we want to (or can) look at images of graphic violence and its aftermath.'' This was prefaced by, ''Thank you for publishing the photo …''

However, another could find nothing to justify its publication: ''Just because it won a Pulitzer prize is no excuse. If they were dead Australians, children or otherwise, you would not print it. Why are Afghans any different?''

I was surprised there was no warning about the confronting nature of the pic. There was a perfect opportunity to include one in the page one pointer, which showed the girl's anguished face with a few words about the image. It could easily have added: ''Warning: this photograph may disturb some readers.'' Despite that, I agree with the editors' decision to publish, which was made after much discussion.

April 18 was the day after the Prime Minister had announced Australia would withdraw from Afghanistan next year. It was a timely reminder of where Australian troops are, what they face there and what the Afghan people will continue to face.

readersed@smh.com.au; twitter: @smhreadersed