Pan Xiangyang was also the first group of students from the Beijing University. He was a scholar and a well-known painter. After entering the school, he gradually developed a strong interest in optics.

China's research on light and imaging has a very long history.

As early as more than 400 BC, the book "Mo Jing" detailed the straight forward of light, the reflection of light, and the imaging phenomena of plane mirrors, concave mirrors, and convex mirrors.

In the Song Dynasty, in Shen Kuo's book "Dream of Dreams and Bi Tan", the principle of "small hole imaging box" was also described in detail.

The first task of students majoring in Optics at Jingshi University is to summarize the knowledge of previous generations and then conduct research.

After entering the school, Pan Xiangyang did not give up his hobbies and still liked to paint. He also learned how to draw sketches here and developed a strong interest in the "realistic school".

Based on the optical principles he learned, he found that the image of an object can be reflected on the wall through a pinhole, and he also recorded it with a pencil.

In August of the first year of Chongzhen, he sprinkled asphalt powder on a glass plate and applied a layer of oil or wax to make it translucent.

In the sun, after a long period of exposure, the white shadow of the fruit can be left behind, making photos that will not disappear.

However, every time you make such a photo, you have to be exposed to the sun for 6 to 8 hours. Such a complicated process is obviously not suitable for actual use.

This prompted him to continue to study imaging techniques.

In September of the first year of Chongzhen, Pan Xiangyang accidentally placed a jade pendant on a metal plate treated with iodine.

He found that the shadow of the jade pendant was printed on the board.

This phenomenon surprised him greatly.

So he asked the old craftsman from the machining factory to grind a metal plate, applied iodine on it, and took photos with a lens, and indeed took a thin shadow.

The success of this experiment greatly encouraged Pan Xiangyang's confidence and allowed him to continue to advance towards the final difficulty of breaking through the development and photography technology.

Here Pan Xiangyang needs to thank Luan Jin because the substance "iodine" was prepared by Luan Jin based on the method provided by Xiao Sheng.

In addition to iodine, Luan Jin also prepared a lot of minerals based on Xiao Sheng’s "Overseas Research Notes".

This provides a good material for the research on chemical engineering of the Academy of Sciences.

Pan Xiangyang continued to look for ways to increase the clarity of the negatives.

By chance, he left the negative film in a cabinet of the experimental potion.

When he discovered it, he saw the negatives that had been exposed in the past, and the image became very clear.

This phenomenon made him very excited. In order to find the answer, he placed an exposed negative film in the cabinet every night.

The next morning, take out a reagent from the cabinet while taking out the negatives.

Using the method of controlling variables, if a certain effective reagent is taken out of the cabinet and then placed in the exposed negative film, it will not be possible to become clear.

But what surprised Pan Xiangyang was that after all the reagents in the cabinet were taken, the negative still showed clear images. This surprised Pan Xiangyang.

In order to thoroughly find out the reason, Pan Xiangyang tossed and checked the cabinet over and over, and finally found some small mercury beads in the cabinet.

So he concluded that the phenomenon must be caused by mercury.

After analysis, Pan Xiangyang inferred that because the temperature in the box is high, mercury evaporation affects the negative film, making it look good.

In order to confirm this judgment, Pan Xiangyang placed the exposed negative film in the dark room and tested it with mercury steam, which achieved the expected results.

In this way, in late October of the first year of Chongzhen, Pan Xiangyang solved the problem of developing the key technology of photography.

Then, in mid-December, he solved the fixing technology, thus completely solving the photography technology problem.

In early May of the second year of Chongzhen, his photography skills were mature and he named it "Silver Photography".

This is a direct positive image method that appears on silver-plated copper plates and cannot be copied through printing and distribution.

It has good clarity, delicate images, and good preservation. Because it is essentially a relief image composed of mercury, viewing from different angles will produce different effects.

In mid-May, dual lenses, reflectors, flash and other configurations were added, and the first relatively satisfactory "camera" was finally completed.

On May 20, he used a camera to take pictures of Zhu Youjian.

Although Zhu Youjian had seen more advanced modern photography technology, he was still very excited to see this black and white photo at this time.

This is a camera independently developed by the Ming Empire, which shows that our Ming Empire also has a group of very capable scientists.

Now the cost of using this camera is quite high at one time, so it is impossible to mass-produce it.

But you can also open a photo studio to take photos of those high-ranking officials and new wealthy businessmen who are not short of money.

Who doesn't want to leave something?

On May 25, the photo studio invested by the Huangxia Chamber of Commerce and co-organized by Pan Xiangyang was opened.

When there was no camera in the past, people would hire painters to paint their portraits, and even sat for three or four hours without moving, just for a picture.

Now, you only need ten silver dollars to leave a completely identical photo. What a good deal!

After Zhu Youjian took his own photos, he placed an order for the photo studio, which was to take one photo for all the concubines in the harem.

Well, although there are only a few people in his harem, this is undoubtedly an advertisement for the photo studio.

So all the officials came to the photo studio one after another, wanting to leave a photo for themselves.

The women of all officials are flocking to this.

Which woman doesn’t want to keep her youth forever, but the destruction of time is irresistible. Then it is also a good way to freeze her beauty on a photo!

The photo studio orders are always in the back row, and after adding new photography equipment, the demand is still not met.

Because there will be more orders every day.

After the preparation of the first year of Chongzhen, Xiao Sheng and Zhu Youjian were behind the scenes. In the second year of Chongzhen, the Ming Dynasty's technology entered a state of explosive development.

The problems that were solved in history that took several years or even decades to solve were solved in the Ming Dynasty in just a few months or even weeks.

Sometimes, those who solve the problem even wonder why they suddenly thought of such a clever way.

All chances are inevitable!

"Folk Science" is developing rapidly, and the technological development speed of the Military Intelligence Bureau has reached the point where it is updated once a month.

Xiao Sheng vigorously promoted the development of basic chemical engineering disciplines, and the most important purpose was to establish a chemical production chain.

Today, the Ming Dynasty musket has developed to the top of the ordinary front-mounted gunpowder rifled flintlock rifle, and the next step is to develop towards the fire cap firing gun.

And the key point is the research and development of the central base fire, that is, the production of fire hats.

This involves the development of chemical substances such as mercury.

In mid-May of the second year of Chongzhen, the first thunder mercury manufacturing plant in the Ming Dynasty was finally completed.
Chapter completed!