All about photo.com: photo contests, photography exhibitions, galleries, photographers, books, schools and venues.
Last Call to WIN A Solo Exhibition this December! Juror: Ed Kashi
Last Call to WIN A Solo Exhibition this December! Juror: Ed Kashi
Jim Ferguson
Jim Ferguson
Jim Ferguson

Jim Ferguson

Country: United States
Birth: 1954

Recently I "remerged" back into the fine art photography world, but this is my second round of showing and selling work. Years back I received a BFA from San Francisco Art Institute and MFA from the School of the Art Institute of Chicago. After getting my BFA, I started contacting galleries. I was successful from the very start with three galleries representing my work and acquisitions by major museums and numerous private collections.

In the fall of 2017 I re-emerged into the fine art world full time, introducing my work again to galleries and museums. Since "reemerging" I’ve had a number of successes. I was in an exhibition at Catherine Edelman Gallery and am represented in their Chicago Project. I’ve been included in exhibitions curated by April Watson, Elizabeth Houston, Douglas Beasley and Robert Klein. I’ve also had a One Person exhibition at Workspace Gallery, and was selected for the Top 200 in Critical Mass 2018.

Wide Range Statement
Traveling through the Southwest for the first time I was photographically hot. My imagery gelled into the beginning of a body of work. This first trip was truly life changing. The Southwest appealed to me so much that I moved to Albuquerque. It served as home base for travels in the West; thus beginning my Wide Range series.

I call this series Wide Range because of the open range nature of the American West and the wide variety of subjects I choose to photograph. Man's isolated impacts on the environment stood out more in the broad expanses of the landscape. I sought not to highlight the negative impacts but to utilize the man-made objects to create my images. The juxtaposition of these man-made objects vs. dramatic backgrounds allowed me to visually compact space into layered unity. This series began the visual journey I've traveled with my photography.

Unfamiliar Places Statement
Unfamiliar Places is a body of autobiographical memories that have been altered by the passage of time rather than by a proactive chemical or digital process. The images were stored on undeveloped film for 20 years, resulting in the degradation of the "latent" image. This work reflect the serendipity that is unique to working with the analogue process and highlights its inherent materiality. The unique process of the degradation of the film over 20 years mirror the historical content of the images.

The images are a result of my photographic journey, the degradation of the emulsion in the negatives and the layering of history with the film wrapper's film numbers and dots. They were taken in France Mexico and the U.S.

Over the past two decades I continued to photograph, standing guard against the instinct for gratification and instead allowing the pictures to rest peacefully in a dark place. It is now thrilling to finally see that the choice to wait offers its rewards: here are the both subtle diminishments and vital revelations in the aging process. Time has left marks on these images just as the events of a life do.
 

Inspiring Portfolios

Call for Entries
AAP Magazine #54 Nature
Publish your work in AAP Magazine and win $1,000 Cash Prizes
 
Stay up-to-date  with call for entries, deadlines and other news about exhibitions, galleries, publications, & special events.

More Great Photographers To Discover

Agata Vera Schiller
Agata Vera Schiller was born in 1980 in Inowroclaw, Poland. Grew up in the countryside surrounded by loving family and beautiful nature. She has graduated at the Faculty of Journalism in Poznan in 2003. Lived for several months in Scotland, spending time drawing and taking pictures of landscapes with her first camera Zenit. In 2006, she has made Masters at the Academy of Fine Arts in Poznan, drawing workshop. Moved to Warsaw and began postgraduate studies at the Department of Interior Architecture at the Academy of Fine Arts in Krakow, which she graduated in 2009. Worked for several years as an interior and furniture designer. In 2010 she moved to Beijing for 3 years, working, living and taking lifestyle pictures. In Beijing began her journey in darkroom focused on discovery old techniques of classical photography such as wet plate. Beijing is also a place, where was held her first solo exhibition „Sol oriens” in 2011 at the Polish Embassy in Beijing, and then at the Chaoyang Culture Center in Beijing. She took part in several collective photo exhibitions in Poland. Her photography is not only a lifestyle photography looking for a beauty in simplicity of Scandinavian interior style and magic of everyday life. But the closest to her heart are nostalgic portraits of women, found somewhere between the worlds, living in a dreams. Agata’s fine art photography is characterized by tension between sensual experience and intellectual construction. Agata currently lives and works in Warsaw as a freelance photographer.
Charlie Lieberman
United States
1945
Charlie Lieberman is a photographer and cinematographer based in Southern California. Best known for his work on the TV show, Heroes, Lieberman has also been developing a body of photographic work since the 1960s. His current practice seeks out humble landscapes, avoiding the iconic in an effort to impart a sense of memory, contemplation, and awe. Lieberman is currently an Active Member of The American Society of Cinematographers. He has been represented by Freed Gallery since 2014 in Lincoln City, Oregon. Statement Whenever I take a photograph, I want you to feel like you are there with me. Whether it is looking through a windshield blurred by rain or standing beside a stretch of weathered, empty highway, I want to impart a sense of memory, even if you have never been to that particular place before. Photographs, like memories, have an elusive power to document experiences that approach each of us in different ways. My work is an attempt to reconsider the preconceptions one might have about landscapes and how we move through them, to direct your eye to experiences that often go unnoticed or taken for granted. By avoiding the iconic, I try to reconnect with a past beyond my own, to a kind of humble, primordial existence where one can converse with the world in solitude. When I do enter the urban landscape, it is always through the impact of light and weather, reminding us of the nature we all inhabit. I document what I consider to be a shy world, a world where stillness and contemplation enable us to walk together and share a common experience imprinted upon the landscape even if the human figure is absent in these photographs. It is this absence I hope to capture with my photography, to allow room for our memories-both real and imagined—to inhabit us with renewed appreciation and awe. Exclusive Interview with Charlie Lieberman
Violeta Sofia
Violeta Sofia is a photographer, artist and activist whose journey is as rich and diverse as her artistic portfolio. Born in Cameroon and raised in Spain from a young age, Violeta's multicultural upbringing deeply influences her work, which often explores themes of identity, diversity, and human connection. From a tender age, Violeta exhibited a passion for the arts, nurtured by her father, a photography enthusiast. At just eight years old, she picked up her first camera, embarking on a lifelong love affair with photography. Despite facing challenges and discrimination during her school years. Violeta persevered, fuelled by her parents' unwavering support for her creative talents. After studying media studies in university, Violeta found herself drawn back to her first love: photography. Her first photography jobs was freelancing in makeover and model agencies, where she developed model portfolios and gained confidence in posing and communicating with subjects. This experience laid the foundation and the confidence to work with high-profile clients, including celebrities, where she often had mere minutes to establish a connection and capture their essence. As a fine artist and portrait photographer, Violeta has made significant strides in the art world. Her work has been exhibited at prestigious institutions such as the National Portrait Gallery and Christie's, showcasing her ability to blend creativity with a powerful narrative. Additionally, she has graced the covers of renowned publications like Elle Italia, Deadline Hollywood, and The Telegraph, cementing her status as a prominent figure in the industry. In addition to her artistic pursuits, Violeta is also a passionate activist, advocating for female inclusivity and representation in the arts. Through her photography, she seeks to challenge stereotypes and highlight the diverse experiences of women, particularly those of colour. Today, Violeta's work transcends mere portraiture; it serves as a powerful tool for storytelling and self-expression. Through her lens, she seeks to bridge divides and celebrate the beauty of human diversity. Whether she's capturing the vulnerability of a celebrity or the authenticity in her fine art photography, Violeta Sofia continues to inspire and challenge perceptions through her art and activism. Statement: In my artistic journey, whether capturing the essence of a celebrity or exploring the complexities of identity through fine art, I am guided by a profound sense of gratitude for the path I've traveled thus far. My photography is not merely a visual expression, but a conduit for protest to fostering connection and understanding. With my conceptual art, my ultimate goal is to contribute to a more inclusive and equitable society. Through the sharing of untold narratives and diverse viewpoints, I strive to dismantle stereotypes and foster a world grounded in diversity, compassion, and positive change.
Nanna Heitmann
Germany/ Russia
Nanna Heitmann is a German/ Russian documentary photographer, based between Russia and Germany. Her work has been published by TIME Magazine, M Le Magazine du Monde, De Volkskrant, Stern Magazine and she has worked on assignments for outlets including The New York Times, TIME Magazine, The Washington Post and Stern Magazine. She has received awards that include the Leica Oscar Barnack Newcomer Award, the Ian Parry Award of Achievement. Nanna Heitmann joined Magnum as a nominee in 2019. Hiding from Baba Yaga "Vasilisa was running faster than she had ever run before. Soon she could hear the witch, Baba Yaga's mortar bumping on the ground behind her. Desperately, she remembered the thin black cat's words and threw the towel behind her on the ground. The towel grew bigger and bigger, and wetter and wetter, and soon a deep, broad river stood between the little girl and Baba Yaga. Vasilisa threw the comb behind her, and the comb grew bigger and bigger, and its teeth sprouted up into a thick forest, so thick that not even Baba Yaga could force her way through. And Baba Yaga the witch, the bony-legged one, gnashing her teeth and screaming with rage and disappointment, finally turned round and drove away back to her little hut on hen's legs." From time immemorial people have sought protection and freedom on the banks of the Yenisei and the adjacent wild taiga. For a long time, the banks of the Yenisei have been pervaded by nomadic peoples. The Russians, coming from the west, chased by the greed for valuable fur, did not reach the river until 1607. Criminals, escaped serfs, apostates or simply adventurers, joined together in wild rider associations and expanded ever deeper into the vast wild Taiga. The life of the settlers in Siberia was free and self-determined for the time. Old believers settled on lonely banks of the Yenisei to escape the persecution of the Tsar and later the Soviets. With Stalin the Yenisei became a place of exile and forced labor. The Soviets not only chained the native peoples, but also the Yenisei. With two giant dams they created lakes of almost 400km length. Villages sank in the water, the climate changed. A dense fog swept over the river. The USSR is history. Today, most people are drawn to big cities like Moscow or St Petersburg. Therefore the Yenisei turns more and more into a space for dreamers and loners to escape the worldly world. Not far from the banks of the Yenisei lives Yuri, who has built a small hut on a landfill. Here he can find food for his 15 former street dogs, here he lives freely. Nothing keeps him in the city, where thick coal dust covers the white snow in winter. "All my friends are in the cemetery. Drugs or alcohol." Following the stream of the Yenisei north one encounters Valentin. An self claimed anarch ecologist - a former officer, traumatized by war missions. Today he lives on his small property in the forest. Even at minus 50 degrees, he sleeps outside by the fire. From endless wars he has enough. "All the people of this world, live together in peace and protect your forests." Only to those who threaten the Siberian forests he declares war. "We have a wonderful forest. How many tress grow here. But we need more forests to breathe. Humanity destroyed our forests. These must be revived immediately. " Not far from the source of the Yenisei, Vaselisa lives in the village of Old Believers. Her parents are both deaf and the only heathens in a village that lives strictly to century-old rituals. She doesn't like the children in her village. Her only friend lives in the village of Sissim. While summer holidays the Yenisei and a walk separates them from each other. Encountering all this different people, there is a bond which connects them with each other. The seek of freedom, protection, imprisonment and isolation. The Yenisei and its woods become a metaphor of a dreamscape: Loneliness, unfulfilled dreams, death, abandoned hopes shape people as much as the vast nature, which at the same time gives so much freedom and places of retreat.
Maia Flore
France
1988
Maia Flore was born in 1988, in France. She is currently living in Paris. Graduated from Ecole des Gobelins in 2010, she joined Agence VU' in 2011. Her approach fits into a research of coincidences between reality and her imagination. Her world is a complete fabrication in form of touching and enchanting narrations, even surrealistic. This is in Sweden she begins her first series "Sleep Elevations", a journey that indulges in childhood memories. During the summer of 2012, while her first residence in Finland, Maia Flore explores new methods of representation and narration. These researches will then continue at the Arts Center of Berkeley, California. Resulting two series (Situations and Morning Sculptures) that continue to explore the feelings of confusion in which the photographer places her characters as her audience. She is exposed for the first time in February 2011 at the festival Circulation (s) of the Young European Photography in Paris. More recently, as part of a White Card from Atout France and the French Institute, Maia Flore depicts the French heritage through her dreamy world in the series "Imagine France – Le voyage fantastique" exposed in Bercy Village until September 2014. In 2015, she wins Le prix HSBC pour la photographie. Source: Agence VU Situations (2012) In the Situations series, a girl runs through varyingly weathered landscapes donning a striking red outfit. In search of a sublime freedom, she travels to find fleeting moments of communion with nature. Draped in red, she catches the light of the sun or buries herself in the fog. As though she were attempting to rediscover this space, she roams on land-locked clouds that evaporate into the landscape upon the return of the sun as it chases away their mystery. Like a game between reality and fantasy, the clash between clairvoyance and a moment of madness, the girl is amused by her emotional confusion. Sleep Elevation (2010) "Those who dream by day are cognizant of many things which escape those who dream only by night," Edgar Allan Poe. This is how these girls, carried away in the air by objects, let themselves travel through boundless landscapes. Flying towards dreamed lands, making real a complete attraction between the character, his ideal universe and the world they live in: that is where these girls lead us. Their contorted movements are merging with the shape of the one revealing their passion. Mix of an imaginary realism and childhood memories, these beings in levitation invite us to dream, limitlessly.
Martin Munkácsi
Hungary
1896 | † 1963
Martin Munkácsi (born Mermelstein Márton; Kolozsvár, Hungary, May 18, 1896; died July 13, 1963, New York, NY) was a Hungarian photographer who worked in Germany (1928–34) and the United States, where he was based in New York City. Munkácsi was a newspaper writer and photographer in Hungary, specializing in sports. At the time, sports action photography could only be done in bright light outdoors. Munkácsi's innovation was to make sports photographs as meticulously composed action photographs, which required both artistic and technical skill. Munkácsi's legendary big break was to happen upon a fatal brawl, which he photographed. Those photos affected the outcome of the trial of the accused killer, and gave Munkácsi considerable notoriety. That notoriety helped him get a job in Berlin in 1928, for the Berliner Illustrirte Zeitung, where his first published photo was a race car splashing its way through a puddle. He also worked for the fashion magazine Die Dame. More than just sports and fashion, he photographed Berliners, rich and poor, in all their activities. He traveled to Turkey, Sicily, Egypt, London, New York, and famously Liberia, for photo spreads in the Berliner Illustrirte Zeitung. The speed of the modern age and the excitement of new photographic viewpoints enthralled him, especially flying. There are aerial photographs; there are air-to-air photographs of a flying school for women; there are photographs from a Zeppelin, including the ones on his trip to Brazil, where he crosses over a boat whose passengers wave to the airship above. On March 21, 1933, he photographed the fateful Day of Potsdam, when the aged President Paul von Hindenburg handed Germany over to Adolf Hitler. On assignment for the Berliner Illustrirte Zeitung, he photographed Hitler's inner circle, although he was a Jewish foreigner. In 1934, the Nazis nationalized the Berliner Illustrirte Zeitung, fired its Jewish editor-in-chief, Kurt Korff, and replaced its innovative photography with pictures of German troops. Munkácsi left for New York, where he signed on, for a substantial $100,000, with Harper's Bazaar, a top fashion magazine. In a change from usual practice, he often left the studio to shoot outdoors, on the beach, on farms and fields, at an airport. He produced one of the first articles in a popular magazine to be illustrated with nude photographs. His portraits include Katharine Hepburn, Leslie Howard, Jean Harlow, Joan Crawford, Jane Russell, Louis Armstrong, and the definitive dance photograph of Fred Astaire. Munkácsi died in poverty and controversy. Several universities and museums declined to accept his archives, and they were scattered around the world. Berlin's Ullstein Archives and Hamburg's F. C. Gundlach collection are home to two of the largest collections of Munkácsi's work.Source: Wikipedia
Andreas Franke
Andreas Franke is in the business for more than twenty years. For Luerzer‘s Archive he is among the 200 Best Photographers. He worked for great brands like Ben&Jerry's, Coca-Cola, Ford, General Electric, Gillette, Heineken, Nike, Visa or Wrigley‘s. His still lifes and his surreal effects are famous. In his pictures every little detail is planned precisely. There is no space left for fortuity. Andreas Franke is a traveler. He travels through the world and between the worlds. His job frequently leads him to several countries on several continents. So does his passion the scuba diving. In his pictures Franke crosses the borderlines between fantasy and real life.With his project “The Sinking World“ Andreas Franke brings a strange, forgotten underwater world back to life and stages realms of an unprecedented kind.The pictures engender extreme polarities: the soft, secretive underwater emptiness of sleeping shipwrecks is paired with real, authentic sceneries full of liveliness and vigor, thus creating a new world, equally bizarre and irresistibly entangling. The resting giants at the bottom of the sea do not only form fascinating and unique backgrounds for Andreas Franke’s sceneries. They also constitute the best exhibition sites imaginable. These spectacular underwater galleries make divers fall under their spell and display the work of the ocean itself. During the weeks and months under water the ocean bequeaths impressive, peerless traces to the pictures. It adorns them with a certain, peculiar patina, endowing them with the countenance of bizarre evanescence and transfiguring them into rare beauties.
Carl De Keyzer
Belgium
1958
Carl De Keyzer (27 December 1958) is a Belgian photographer. Major subjects in his work have included the collapse of Soviet Union and India. He became a full member of Magnum Photos in 1994. De Keyzer has exhibited his work in many European galleries and has received several awards, including the Book Award from Rencontres d'Arles, the W. Eugene Smith Award and the Kodak Award.Source: Wikipedia Carl de Keyzer started his career as a freelance photographer in 1982 while supporting himself as a photography instructor at the Royal Academy of Fine Arts in Ghent, Belgium. At the same time, his interest in the work of other photographers led him to co-found and co-direct the XYZ-Photography Gallery. A Magnum nominee in 1990, he became a full member in 1994. De Keyzer likes to tackle large-scale projects and general themes. A basic premise in much of his work is that, in overpopulated communities everywhere, disaster has already struck and infrastructures are on the verge of collapse. His style is not dependent on isolated images; instead, he prefers an accumulation of images that interact with the text.Source: www.carldekeyzer.com Magnum photographer Carl de Keyzer was born in Kortrijk, Belgium, in 1958. In his early work he focused on social groups outside of the mainstream. The God, Inc. series explores the various sects of Christianity in the United States and the drastically different and often extreme ways in which people communicate with God. Currently de Keyzer is tackling large-scale projects and general themes relating to overpopulated communities, disasters, and infrastructures. He prefers to work with an accumulation of images that interact with text, and in a series of large tableaux he has covered India; the collapse of the Soviet Union; and modern-day power and politics. His photographs have been published in The Guardian, LIFE, El País and Le Monde, and de Keyzer’s works are held in collections including the J. Paul Getty Museum and the Fotomuseum in Belgium. He also is a recipient of the W. Eugene Smith Grant for Humanistic Photography.Source: International Center of Photography Carl De Keyzer tackles large-scale themes through an accumulative, expansive approach. He builds up narratives through collected images, which often interact with text (taken from his travel diaries). In a series of large-format prints, he has covered India, the collapse of the Soviet Union and – more recently – modern-day power and politics in North Korea. His seminal project, God, Inc., captured religious life on the margins of American society. A basic premise in much of his work is that, in overpopulated communities everywhere, disaster has already struck, and infrastructures are on the verge of collapse.Source: Magnum Photos
Advertisement
AAP Magazine #54 Nature
Win a Solo Exhibition this December
AAP Magazine #54 Nature

Latest Interviews

Exclusive Interview with Ghawam Kouchaki
American photographer Ghawam Kouchaki brings a sharply observant and introspective gaze to the streets of Japan’s capital. Based in Los Angeles, he approaches Tokyo with the distance — and curiosity — of an outsider, allowing him to uncover the city’s subtle contradictions, quiet tensions, and fleeting gestures that often go unnoticed. His series Tokyo no no, selected as the Solo Exhibition for December 2024, explores the hidden undercurrents of urban life: the unspoken rules, the small ruptures in routine, the poetic strangeness found in everyday moments. Through muted tones, instinctive timing, and meticulous framing, Kouchaki reveals a Tokyo that exists somewhere between reality and imagination — both intimate and enigmatic. We asked him a few questions about his life and work.
Exclusive Interview with Tommi Viitala
Tommi Viitala, winner of AAP Magazine #44: Street, is a Finnish photographer celebrated for his striking and cinematic street photography. With a keen eye for atmosphere and composition, he captures fleeting urban moments that reveal the poetry of everyday life. His work often explores the tension between solitude and connection within contemporary cityscapes, blending documentary realism with artistic sensibility. Viitala’s photographs have been exhibited internationally and recognized for their strong visual storytelling and emotional depth. We asked him a few questions about his life and work.
Exclusive Interview with Robert Mack
Robert Mack is a California-based visual artist, photographer, and filmmaker. His fine art photography and films have been exhibited widely in the United States and Europe, with major shows at the Baltimore Museum of Art and the Reiss-Engelhorn Museum in Mannheim, Germany. Both institutions hold his work in their permanent collections. Working across different media, Mack has built a career exploring the complexities of human presence and representation. In 1981, while living in Baltimore, he produced The Perkins Project: Not Guilty by Reason of Insanity, a rare photographic and film study inside Maryland’s hospital for the criminally insane. These stark yet compassionate black-and-white portraits remain one of his most powerful and controversial bodies of work.
Exclusive Interview with Alan Schaller About Irys
Alan Schaller is a London-based photographer best known for his striking black-and-white street photography and as co-founder of Street Photography International, one of the largest online communities dedicated to the genre. With years of experience both behind the camera and in building platforms that give visibility to photographers, Schaller has now turned his focus to creating a new digital space for photography itself. His latest venture, Irys, is a photography app designed by photographers, for photographers, with the aim of offering a dedicated platform where images are respected as works of art rather than treated as disposable content.
Exclusive Interview with Guillaume Bonn
With his latest book Paradise, Inc., celebrated documentary photographer Guillaume Bonn takes us deep into the heart of East Africa, where the promises and failures of wildlife conservation collide. Far from offering a romanticized vision of nature, Bonn’s work confronts us with urgent realities: the tensions between local communities and conservation policies, the sacrifices of rangers on the frontlines, and the long-lasting impact of human activity on fragile ecosystems. Spanning more than two decades of fieldwork, the project blends powerful imagery with investigative depth, raising difficult but necessary questions about transparency, accountability, and the Western-led models that dominate conservation. Enriched by the voices of those too often left out of the conversation—including a preface by Maasai leader Ezekiel Ole Katato and an introduction by journalist Jon Lee Anderson—Paradise, Inc. is both a stunning visual journey and a call to action. In the following interview, Guillaume Bonn reflects on the making of Paradise, Inc., the ethical dilemmas at the heart of his work, and the urgent need to rethink our approach to conservation in East Africa and beyond.
Exclusive Interview with Sander Vos
Sander Vos is a fine art photographer based in London whose work seamlessly blends elements of Surrealism with portraiture. Drawing inspiration from his background in design, Vos embraces light and contrast to sculpt striking, graphic compositions. His photographs invite the viewer into a world where revelation and concealment coexist, leaving space for imagination and interpretation.
Exclusive Interview with Tomasz Trzebiatowski Editor-in-chief FRAMES Magazine
Founded in 2020 by photographer, publisher, and classical pianist Tomasz Trzebiatowski, FRAMES Magazine has quickly established itself as a thoughtful space for photography lovers who believe that powerful images deserve to live on paper. Known for its beautifully printed quarterly issues and dynamic international community, FRAMES bridges the gap between tradition and innovation in the photographic world. As editor-in-chief, Trzebiatowski has created not only a publication but a platform that celebrates diverse genres, nurtures dialogue, and champions the tactile experience of print in a digital age. In this interview, he reflects on the journey from founding FRAMES to building a global membership, the challenges of independent publishing, and the future of photography in both print and digital forms.
Exclusive Interview with Manuel Besse
French photographer Manuel Besse is known for his compelling black-and-white imagery, which blends portraiture, documentary, and poetic narrative into a singular visual voice. With a career spanning several decades and continents—from the gold mines of Serra Pelada to the Arctic Circle—his work reflects a deep commitment to authenticity, human connection, and the preservation of cultural and natural landscapes. His series Macadam, winner of AAP Magazine #41 B&W, offers a contemplative look at fleeting urban encounters, rendered in his signature monochrome style. We asked him a few questions about his life and work.
Exclusive Interview with Matthew Portch
UK-born photographer Matthew Portch brings a quietly cinematic eye to the overlooked landscapes of suburban and rural America. Now based in Arizona, his photographic journey reflects a long-standing fascination with the cultural imprint of mid-century America—filtered through a distinctly outsider’s perspective. His series Lost America, selected for the September 2024 Solo Exhibition, captures an eerie stillness in the built environments of the American West, where nostalgia, silence, and isolation converge.
Call for Entries
Win A Solo Exhibition in December
Get International Exposure and Connect with Industry Insiders