Chapter 62 Extracting Fingerprints


Chapter 62 Extracting Fingerprints

Fingerprint identification and analysis should be said to start from fingerprint collection.

The quality of fingerprint collection fundamentally determines the difficulty and probability of success of fingerprint identification analysis.

Lu Chuan has completed collecting the fingerprints on the frame.

This time, Lu Chuan did not use ordinary silver powder or rarely used copper powder, but used the magnetic adhesion method to collect it.

This is because the picture frame is made of composite boards pressed from broken wood and then painted.

Compared with several commonly used fingerprint collection methods, magnetic adhesion to collect fingerprints on the surface of this carrier has the best effect and causes the least damage to fingerprints.

At the same time, due to the twisting of fingers during the transportation process, many fingerprints on the frame have scratches.

This kind of fingerprint collection is also suitable for magnetic adhesion.

“Master, the fingerprints on the frame are mixed. There must have been multiple fingerprints left behind during the transportation back and forth. It’s hard to say whether there are fingerprints of the suspect in it.”

Liu Guodong nodded.

I just heard from the action team that the artist who signed the painting has been found, but the other person said that he had never painted the girl in the waves of wheat.

So, it is currently impossible to identify who the murderer is.

"The focus now is on the fingerprints on the paint and the fingerprints on the skin. You will be in charge this time. If we need our cooperation, you will arrange it."

Lu Chuan nodded: " I’ll try it first. There are still some things I need to communicate with Shen Yan.”

Lu Chuan had a way to collect fingerprints on the paint, but collecting fingerprints that may exist on the skin would most likely require destroying the resin pigment on it.

This will have an impact on the skin itself, which naturally requires the consent of a forensic doctor.

In the laboratory, Lu Chuan turned off all the lamps, used an ultraviolet portable lamp, and observed the paint inch by inch.

Oil painting is different from Chinese painting. The pigment itself has a grainy feel. During the painting process, the painter can also use lines of different shades to reflect the changes in space.

So, oil paintings look more realistic, the contrast between light and dark is stronger, and the sense of space is stronger.

However, this is not a good thing for fingerprint collection.

The wheat waves in the picture seem to be really dancing in the wind.

During the ups and downs, Lu Chuan has discovered some fingerprints.

However, these fingerprints have many breakpoints, and basically every line has a breakpoint.

In addition, the pigments in this oil painting are minerals and contain elements such as sodium, iron, and copper.

Therefore, in this case, ordinary physical and chemical methods will fail.

This time, Lu Chuan still needed to use a variable frequency laser spectrum analyzer to develop fingerprints.

However, unlike developing fingerprints on paper, the wavelength of the laser required for development on oil paintings varies.

Fortunately, among the intermediate fingerprint collection skills, there is a reserve of experience in this area.

Lu Chuan only needs to constantly adjust the wavelength to develop fingerprints on different pigments, and then piece together the developed fingerprints from each section through photos to complete the collection.

In the dark laboratory, Lu Chuan was constantly adjusting the laser frequency of the instrument, and segments of fingerprints kept flashing.

Liu Guodong cooperated and recorded every fragment of fingerprints with a camera.

While Lu Chuan was extracting fingerprints from the paint, the investigation of Operation Two was also underway.

However, the effect is far from ideal.

Zhang Bin, the person in charge of the exhibition hall.

"I really don't know where this painting came from."

"You have just seen the specific information. The painter is Liang Song, a local grassroots painter in Haizhou. You should ask him."< br>
The person in charge of exhibition arrangement in the exhibition hall. "These paintings are all donated. Except for a few more expensive paintings that are on loan for the exhibition, the others were invited by the painters to contact us or we invited them to be displayed in the exhibition hall."



“You don’t have any review mechanism for exhibition paintings?”

"Yes, there are, but there are not many painters in Haizhou, and there are even fewer excellent paintings. As long as they are similar, we will put them in the exhibition."

"The level of this cultural and art exhibition is not high. Gao, although Liang Song is a grassroots painter, he is actually quite famous in Haizhou City.”

“Then how did this painting get into the exhibition hall? Who moved it from where?”

"On Thursday, the exhibition installation was completed just the day before yesterday. We have a professional moving team, and we sent people directly to Mr. Liang Song's studio to move the paintings..."

Action Group Responsible inquiry indoors.

Liang Song is a man in his fifties with a mustache and the temperament of an artistic uncle. In the interrogation room at this moment, there is no nervousness or fear in his eyes like ordinary people.

Sun Jun could tell that Liang Song seemed curious and kept looking at everything around him.

"Mr. Liang, you don't seem nervous at all?"

Liang Song stopped looking and looked at Sun Jun: "Why should I be nervous?"

"There are not many people who are not nervous after entering this place."

"That's because they committed a crime. I didn't do anything illegal, so of course I'm not nervous, but..."

Liang Song changed his tone: "When I go back, I can make a picture based on my experience in this inquiry. Painting is called... it's called freedom. What do you think? "

Freedom?

Sun Jun was dumbfounded: "Mr. Liang, I think it is better to lose freedom."

"Okay, let's talk about your painting."
< br>

Liang Song shook his head: "I told you in the car, that painting was not painted by me."

"Although I often paint wheat waves and some rural-themed works, the girl in the wheat waves you are talking about , it’s really not my painting.”

“But the painting is signed by you, and according to the explanation from the exhibition venue, this painting was shipped from your studio.”

Liang Song frowned deeply: "Officer Sun, I really don't know what's going on."

"I know about this art exhibition. They sent me an invitation letter."

“I also agreed to exhibit my paintings for them, and to be honest, I also hope they can exhibit my paintings.”

“As a grassroots painter, I don’t have a teacher, so I paint by myself. "

"So, I cherish this exhibition opportunity."

"Furthermore, from the photo of the painting you showed me in the car, I knew that the painting was by Mai Lang. It’s really good, but the painting is really not mine.”

“The painting I gave them was called Dry Well Next to the Wheat Field.”

“In the reply to the exhibition hall, there is the name of the painting.”

“If you don’t believe it, you can go to my studio to see it. If there are any mistakes, then the painting of the dry well next to the wheat field should be restored. In my studio."

"In addition...as for whether this painting was painted by me, you can also ask some famous painters to identify it. It is not difficult..."

Afternoon. Six twenty-eight.

In conference room No. 1, Qin Yong presided over the first case analysis meeting.

"The action team, the investigation team, and the forensic scientists have all talked about what progress has been made now?"

(End of this chapter)

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