Rosa Park-Chen brings a former athlete's understanding of peak moment to photography criticism: the precise physical knowledge of what a body at maximum effort looks like, and the ability to judge whether a photograph captured the right millisecond or the next one. She has contributed to Light & Composition since 2020.

In sports photography, a tenth of a second is the difference between a great photograph and a record of what almost happened. The peak moment in athletics is physiologically precise — there is one frame where the body is at maximum extension, maximum tension, maximum expression. One. The photograph either found it or it did not.

Sophie Delacroix approaches photography criticism through the lens of perceptual psychology. She has been with Light & Composition since 2013. Her criticism focuses not on what is in the image but on what the image does — the sequence of emotional and cognitive responses it triggers in a viewer who has never seen it before and the one who returns to it a year later.

The photograph is not the thing in the frame. The photograph is what happens in the body of the person looking at it. A great image alters the viewer's physiology — pulse, breath, the specific sadness of a certain blue.

Amara Diallo came to photography criticism through a deep conviction that every portrait is an act of storytelling — a conviction rooted in the oral traditions of West Africa, where the story is the record. He has contributed to Light & Composition since 2014. For Amara, the most important question a portrait photographer can answer is: did you listen before you looked?

Before the shutter, there must be a conversation — even if it is silent. The photographer who listens to their subject before looking at them makes a different kind of portrait. You can see it in the eyes. You can feel it in the frame.

Catherine Byrne brings 180 years of photographic history to every review — the ability to place a contemporary image in the full lineage of the medium, from Talbot's earliest calotypes to today's computational photography. Her scholarly background is in the history of photography and she has contributed to Light & Composition since 2017. She is the panel's most historically demanding voice.

Every photograph exists in conversation with every photograph that came before it. Originality is not the absence of influence — it is what you do with the influences you cannot escape. I ask of every image: where does this sit in the long conversation? What does it say that has not been said before, and what does it say better?

Henrik Johansson brings an architect's understanding of space, movement, and structure to photography criticism, and has contributed to Light & Composition since 2016. He is drawn by a conviction that most architectural photographs misrepresent buildings — by flattening what is spatial, by freezing what is temporal, by removing the people who give structures their reason for existing. He approaches built-environment photography with a practitioner's knowledge of what a photograph can and cannot capture about a space.

Architecture exists in time and movement. A building is not a single view — it is a sequence of experiences. The architectural photograph is always a lie of convenience. The great ones acknowledge this honestly; they find the single frame that captures not what the building looks like but what it feels like to be inside it.

Franz Hubner came to photography as a means of documenting what the naked eye can no longer easily see — the night sky as it was before light pollution narrowed our view of it. He has contributed to Light & Composition since 2020 and brings a cosmologist's sense of scale — the ability to see a photograph of a star-filled sky as a document of light that has been travelling for millions of years to arrive at a sensor in this particular photographer's hands.

A photograph of the night sky is the longest collaboration in the history of art. The light in the frame left its source before humans existed. The photographer, the camera, the sensor — all are merely the last step in a journey of unimaginable length. That responsibility deserves to be taken seriously.

Deepa Krishnan brings both a scientist's knowledge of marine ecosystems and a technical understanding of the profound optical challenges of underwater photography — the light absorption, colour shift, and backscatter that make every good underwater image a minor technical triumph. She has contributed to Light & Composition since 2019.

The underwater world follows different physical laws. Light is stolen by water — red disappears at five metres, orange by ten, yellow by twenty. The underwater photographer is working in a world that actively removes colour. Every image that has warmth and clarity below the surface has fought for it. I respect that fight, and I can tell when the photographer understands the physics of what they are doing.

Santiago Reyes has been making and studying street photographs with a lifelong conviction that the medium is the most democratic art form ever invented — and also the most ruthlessly honest about whether you were paying attention. He has contributed to Light & Composition since 2018.

The street gives you one chance. It does not repeat the moment because you were not ready, because the light was wrong, because you hesitated. The decisive moment is decisive because it will not wait. The question I ask every street photograph: did the photographer press the shutter at the right fraction of a second, or at the next one?

Thomas Hargreaves brings a landscape practitioner's uncompromising standards to photography criticism. He has contributed to Light & Composition since 2010 and is the panel's most demanding voice on the subject of craft — specifically the craft of waiting, of returning to the same place in different weather, of earning the photograph rather than finding it. His dry wit has made him the panel's most quoted critic and occasionally its most feared.

The best photographs are expensive. They cost the photographer time, patience, and physical discomfort. I can usually tell from the image whether someone paid full price.

Marcus Trent brings a photojournalist's intolerance for artifice and his deep conviction that every worthwhile photograph is ultimately about a human being — either because a human being is in it, or because a human being felt something extraordinary in the moment they pressed the shutter. He has been reviewing for Light & Composition since 2015.

Photography is a human act before it is an aesthetic one. The question I ask every image: did the person behind the camera feel something true? If they did, the camera finds a way to carry it.

Valentina Marchetti, whose background bridges art history and documentary photography, has contributed to Light & Composition since 2019. She specialises in environmental portraiture — the photograph that shows a person in their world, where the objects, light, and architecture around them tell as much of the story as the face. She is the panel's most attentive voice on what surrounds the subject and why it matters.

The environment is not the background. The environment is half the portrait. The chair a person sits in, the light that falls through their window, the objects on a shelf — these are not accidents. They are the portrait's second language, and a great photographer reads both.

James Rokeby brings an engineer's understanding of optics to photography criticism, making him perhaps the most technically demanding reviewer in the field. He has contributed to Light & Composition since 2013. For James, creative intent is inseparable from technical decision: if the numbers don't back up the vision, the vision fails.

Every creative decision leaves a trace in the EXIF data. Aperture, shutter, ISO — these are not settings, they are arguments. Bad technical choices cannot be rescued by good subjects.

Eleanor Voss has contributed to Light & Composition since 2011. A committed formalist, she believes that a photograph's enduring power lies almost entirely in the rigour of its visual architecture — the placement of mass, the tension of negative space, the discipline of the frame. She has little patience for sentiment without structure.

A photograph earns its place through formal rigour alone. Emotion without structure is noise. The frame either holds or it doesn't.

Nadia Osei is one of the most respected — and challenging — voices in photography criticism. She has contributed to Light & Composition since 2016 and has never allowed a photograph to rest comfortably in its own assumptions. Her reviews ask questions that other critics are afraid to pose.

Every photograph is an act of looking. And looking is never neutral. Who is the photographer? Who is the subject? What does the frame include, and what does it exclude, and why? These are not political questions — they are photographic ones.

Mei-Ling Chen, whose background spans visual design and applied mathematics, has contributed to Light & Composition since 2015. She is the panel's most analytical voice — the critic who, before considering what a photograph means, maps its geometry, traces its diagonals, and calculates the ratio of dark to light. She believes every great photograph solves a spatial problem.

The frame is a mathematical space. Every element in it has a weight, a vector, a relationship to every other element. Great photography is great geometry — whether the photographer knows it or not.