When I was first handed the task of co-ordinating user-generated images for Reuters, I was inundated with pictures of people and their pets and newborn babies. They werent exactly the pictures we were striving for when we launched You Witness News.

Now, I am pleased to say, I am seeing some high-quality images from major news events and global sports stories.

What I wasnt expecting was an insight into a secret society such as North Korea. Images by aspiring photographer Nora Stribrna raised the bar on user-generated content.

Nora, a Czech native and air stewardess on a private jet of a member of the Saudi royal family, tells the story behind the pictures:

North Korea opens its border twice a year to showcase its Arirang Mass Games, where it celebrates its military might and communist ideology. My ex-boyfriend is a photographer and he alerted me to this opportunity to visit the isolated nation. After applying for visas for us both at the North Korean embassy in Prague, he attended the mandatory How to behave in North Korea lessons that the embassy held for upcoming visitors. As I was not in the country, I missed hearing first hand all the useful tips, like what to wear (long sleeves and no shorts) and how not to be extravagant.

So we flew to China and were off: 23 foreigners on a 26-hour train ride into North Korea. The train was poor, devastated and dirty but we all expected it. When we reached the Chinese-Korean border, we all became scared. Nothing was allowed to be brought in, so we all left our mobile phones and computers in China, all books and weird items as well. Every person was searched properly, bag by bag, person by person, and many questions were asked by immigration officers. After being searched and questioned for six hours, we had some time to kill.

My first shock: everybody in green, gray and black uniforms, nobody spoke, heads down, silence, few bicycles, dark atmosphere, everywhere guards and police, barking dogs, fear. But there was revolutionary music playing, trying to make people happy.

We traveled with three official escorts, who were there to observe, control, listen to and ask us a lot of questions. One of them even spoke Czech to be sure they could understand what we said to each other.

Pyongyang, the capital, is made for the world to see how rich North Korea is. There are some buildings, airports and a few hotels. There are no shops or supermarkets. People are given vouchers for food, and are given few clothes a year. All uniforms. There are no other clothes.

We traveled to the north and south and saw indescribable poverty, peasants taking care of rice, guarded by police and military, just to make sure nobody would escape. Everything is black, gray, brown. People never put their head up.

One of our guides quizzed me on the members of our group: asking what is their occupation, their purpose for coming to North Korea and what the journalists in our group were planning to publish. I was asked to tell them to publish only good things about the regime.

After five full days, our initial laughter had passed. All except one of us had lived in communist states and we all remembered those similar days. Nobody really spoke on the plane back to Beijing. I only remember, we all got very drunk that night back to China. And we were very grateful for water and electricity. Very. We could speak! And we could say whatever we wanted.

You can see more of Nora’s pictures from North Korea here

There are many types of photograph that fall into the category of the marmalade dropper or the ‘cornflake dropper’. The phrases refer to astonishing pictures, or stories, that cause the reader of her/his morning newspaper to drop the marmalade or cornlflakes in mid-bite. More often than not it is the unexpected nature of the subject matter within the photograph that causes the extreme reaction. There are lots of examples, but the ones that always catch my eye are the photographs that combine luck and skill, resulting in an image that appears both familiar and yet unfamiliar at the same time.

By its nature a photograph is two dimensional, and gives the impression of a third dimension through light/shade and perspective. But sometimes the everyday elements within the frame come together to create something unfamiliar, creating, in my view, a fourth dimension in the image, almost an optical illusion, stopping us in our tracks and enticing us to take another look and another.

These photographs are quite rare, because in order to work they have to be perfectly composed. Given the scale and scope of the Reuters picture operation I was able to find three such photographs shot within a 24 hour period.

The first photograph, by Denis Balibouse, shows US golfer Paula Creamer marking her ball in the 14th women’s Golf Masters in France. We immediately recognise what we are looking at, but the more we look the less familiar the image becomes.

The photograph of Barcelona’s Thierry Henry, by David Moir, diving for the ball in Edinburgh makes us look twice as his head appears to be replaced by the ball.

Synchronized swimming always makes striking images, and in this photograph by Daniel Munoz the legs of the U.S. team competing in Rio de Janeiro create an interesting pattern.