With his wavy hair streaming in the wind, the famous tourist sailed along the Dutch coast. A whale that was "100 fathoms" long had reportedly been washed ashore, as he noted excitedly in his diary. He was determined to sketch this monster.

But when the ship reached the beach in question on Dec. 10, 1520, the animal had been washed away.

Nonetheless, this date is widely thought to be a turning point in the life of Albrecht Dürer. Soon after this journey, he was plagued by fever and fainting spells. On one sketch, he points to his spleen: "That's where it hurts." It went on like this for years. When he died, he was "dried out like a bundle of straw," according to a contemporary.

Until now, researchers were certain that Germany's greatest painter was suffering from malaria. The theory was that he had contracted the deadly parasite in the swamps of the north.

But is the theory true? Microbiologist Hanns Seitz from the University of Bonn has conducted an initial analysis of all historical notes on the artist's symptoms and pains. He has concluded that the previous diagnosis was "clearly" wrong. During the winter, the risk of transmission from infected mosquitoes was virtually nonexistent -- even back then.

But this begs the question: What was Dürer really suffering from? What weakened him? Was he perhaps ravaged by syphilis, which he so feared?

Achieving Perfection

And, more importantly, what kind of man was this genius, who brought the Renaissance over the Alps 500 years ago and used a brush made of guinea pig hair to paint his finest strokes? The man from the southern German city of Nuremberg stands like a titan at the dawn of the new age. He emerged from the darkness of the Middle Ages like a god of color.

Dürer strove to reproduce every detail, from a hare's whiskers to the pistil of a wildflower. To achieve this perfection, he obsessively studied anatomy and nature. Nobody could better paint skin pores or the luster of a single hair.

But how did the master work? To shed more light on this secret, the Germanisches Nationalmuseum in Nuremberg has launched an exciting project. Ahead of an exhibition of Dürer's early works, which runs from May through September, more than 20 oil paintings were X-rayed and examined using infrared spectroscopy. It is the biggest ever exhibition of the painter's early works with more than 200 oil paintings and drawings on display.

The rays penetrated the layers of paint to provide a direct view of the canvas.

Toiling at His Easel

For three years, the team traveled from the Prado in Madrid to museums as far away as New York and Washington. In Florence, the sleuths were even allowed to remove "Adoration of the Magi" (estimated value: €100 million; $132 million) from its frame. This examination revealed preliminary sketches, with center points from compasses, and dogs and buildings painted over later on. The artist sketched some of his works completely, in charcoal or ink.

The X-rays show for the first time how this man toiled at the easel -- how he planned, tested and discarded his ideas. Sometimes he slapped thick paint on the canvas and worked it with the tip of his brush handle. On other occasions, he painted with his thumb and the ball his hand.

When he painted "Salvator Mundi" in 1504, he struggled and pushed himself to the brink. The oil painting depicts Jesus Christ with a glass sphere in his hand. Now, an infrared examination has revealed the remarkable plan that the master originally pursued.

The frame and crossbars of a window were to be mirrored on the left-hand side of the glass sphere, and reflected once again on the other side of the ball, before subsequently casting a pale reflection on the messiah's robe. The painter even wanted to take into account the refraction in the glass and the fold in the fabric.

But he failed. "Salvator Mundi" was never completed.

Outdoing Himself

"Dürer differentiated between hastily made cheap art, works of good quality and those where he brought to bear his complete range of skills," says curator Thomas Eser, as he sums up the results of the high-tech examination.

When it came to his finest canvases, this creative mind spared no expense. He put ultramarine made from lapis lazuli on his palette, along with a crimson red paint made from Polish scale insects. He used gold leaf and purple pigments made from Brazilwood.

In the year 1500, he outdid himself. After more than six months of work, he created a self-portrait, wearing a fur collar coat with his hair in a mane of curls. Hundreds of individual beard hairs were painted in detail. The painting seemed so deceptively realistic that his own dog supposedly barked at it.

Why go to so much effort? Self-portraits of the highest quality were created in the studio of this exceptional artist. None of them were ever sold.

The researchers at the Germanisches Nationalmuseum have presented an explanation to this puzzle: The up-and-coming head of the atelier needed samples of his work to attract customers. He wanted to dazzle and beguile them with his talent. Later, he hated this "fiddly work," as he called it. It brought him fame, but meager earnings.

He really raked in the money, though, with his copperplate prints and woodcuts. His images entitled "Apocalypse with Pictures" from 1498 were so bold and novel that the Christian world lined up to buy them.

Astonishingly Modern

This gifted artist was called a "genius" and a "teacher of worlds." The 19th century romanticized him as a devout German craftsman with a long beard.

Total nonsense: Dürer was astonishingly modern. He had already begun painting in the open air and signed his works with a monogram -- the beginning of the copyright. Agents sold his woodcuts, which were reproduced on presses, to customers as far away as Spain and England. He was widely famous even during his lifetime -- the art world's first international star.

The artist seemed amazingly close to the present in many other ways, too. No one before paid such homage to his own self, and no one broke so many taboos. In 1493, he sketched a naked whore -- the first nude north of the Alps. In 1517, he ventured a detailed depiction of a scrotum -- a pioneering act in the West.

Some of Dürer's drawings are so suggestive that researchers kept them secret for years and locked them away in the closet. One example is the drawing "Youth with Executioner." It shows an executioner, armed with a sword, who is stroking a half-naked young man, who voluptuously acquiesces. Other sketches also show naked men's bodies.

What desires drove this man? Recently, the doyen of Dürer research, Matthias Mende, 74, broached the taboo issue and identified in the work of the "most German of all German artists" -- as the Nazis called him -- a "sexual background noise" that tends toward "sodomy."

During the late Middle Ages, this category also included anal sex.

Austere Early Days

Contrary to what was long believed, he wasn't much of a cosmopolitan. True, the British Museum has praised him as "truly international," and he is said to have traveled as a young man to Holland and Flanders, and visited the Italy of the Quattrocento, or 15th century.

But in reality this speculation is highly doubtful. Recent studies show that Dürer didn't dare travel abroad at first. Instead, he thrived among the taverns and sausage stands of his home region.

This lack of traveling, however, doesn't necessarily mean a provincial narrowness. Nuremberg was the second largest city of the Holy Roman Empire. A population of 45,000 lived behind the town's walls. The neighborhood surrounding Dürer's atelier on Burgstrasse was home to doctors, historians, globe makers and merchants who traded with foreign countries.

The boy grew up in these surroundings. First, he was an apprentice with his father, a goldsmith. He made his first self-portrait at the age of 13, and proudly wrote along the edge: "I used a mirror to paint this image of myself."

At the time, rich merchants liked to commission portraits. The bourgeois ego cult was only just emerging. Dürer wanted to take part in this boom. In 1490, he got started and painted his parents as a test.

The recent infrared examination has divulged how sparing the apprentice had to be with materials. For the portrait of his mother, he used a threadbare piece of cloth made of flax. "It looks like an old towel," says Oliver Mack, who works as a restorer. Researchers would be only too happy to find out more about these austere early days, but the source information is patchy.

Setting Out on a New Journey

What is clear, though, is that Dürer went wandering at the age of 18, and his travels took him to Alsace and Basel.

Whistling a happy tune, with his rucksack and his hiking stick -- that's how the Romantic Movement imagined the teenage Dürer. In reality, he frequented whorehouses. A self-portrait from this period shows him looking downcast and emotionally distraught, like van Gogh.

Finally, the vagabond returned home. His father had arranged for him to marry a patrician's daughter. They were wed on July 7, 1494. But shortly after the wedding, the newlywed husband set out on a new journey.

What was going on here? Until now, art historians have explained the hasty departure as follows: Dürer is said to have traveled to Italy to immerse himself in the world of the Renaissance, just as author Johann Wolfgang von Goethe and archaeologist Johann Joachim Winckelmann did centuries later. The artist's destination was supposedly Venice.

Radically Different Interpretation

This theory, however, is apparently not true. Sure enough, the lagoon city was at the height of its glory. The fragrances of Indian spices wafted from the port. Pagan antiquity was enjoying a renaissance here, as well: 11,000 prostitutes offered their services.