This director needs to apologize

Chapter 99: Motion blur swarms over
Of course Sang Ping and Paul knew about the "time freezing" technology. After Chen Yiming explained it briefly, they deduced the general effect on their own.

Basically, when the truck "overtakes" the squirrel, the camera freezes frame by frame as the squirrel's head rotates, ultimately showing the dynamic effect of the squirrel and the truck chassis above it rotating together.

The movie is shown at 24 frames per second. Assuming that the "freeze" time of the intersection of the squirrel and the truck is set to 1 second, that is 24 freeze-frame images.

In fact, it is not necessary to collect 24 frames, because the human eye itself has a motion blur function. As long as a minimum number of key frames are retained, the human brain can complete the motion trajectory on its own when receiving information.

Paul has more experience in mobile shooting, so he immediately raised a question. Squirrels can indeed be made with CG. Trucks and dirt roads always have to be shot in real life. How to fill in the detail changes during freeze-frame rotation?
Paul's question involves the essential difference between a video camera and a camera.

Both are actually derived from the principle of reflection imaging, except that the camera is a static single-frame exposure, while the camera is a dynamic frame-by-frame continuous exposure.

For the same scene, the camera takes a photo, and the camera takes a video, but the length of the video is only one second, and the camera needs to be exposed 1 times continuously at intervals of 24/24 seconds.

If you extract these 24 frames and develop them into photos, and then compare them with the photos taken by the camera, you can clearly see the difference between the camera and the camera, especially when shooting moving objects.

The 24 photos taken by the camera are different, not only the object itself, but also all elements in the viewfinder such as background, light, color, angle, etc.

These 24 photos are combined together to deliver the "motion blur" effect to people's eyes.

The reason why it is 24 comes from repeated trials at the beginning of the invention of the camera. Only a "playback" speed of 1 frames per second is the most comfortable for human eyes.

It can be seen that the achievement of dynamic blur effect is the result of the interaction between the camera and the human eye.

This also determines that the camera cannot perfectly simulate motion blur through the "continuous shooting" function.

Specific to "time freezing", the camera array can indeed achieve continuous shooting and multi-angle freeze-frame at the same time, but it is only suitable for green screen shooting, that is, all variables that cannot simulate changes such as background, light, color, etc. are removed.

Therefore, when time is frozen in movies, large close-ups are often used to blur the background.

Paul's doubt lies in this point. The squirrel is simulated using CG technology, so it can naturally be mounted on a camera array. Anyway, it is all done through computer virtual modeling.

However, the truck chassis passing above its head and the receding dirt road are all real scenes. How to deal with this part?

Chen Yiming could explain this problem, but he still asked Xiangrui to call Zhao Lu, the team engineer from Jushi Workshop.

He arrived yesterday. After following the car to the location today, Chen Yiming couldn't find anyone. He was probably looking around for the scenery.

Seeing Chen Yiming's confident attitude, Sang Ping and Paul stopped asking further questions.

After hanging out together for a month, the two of them already had some understanding of Chen Yiming, and knew that this was not a person who just talked nonsense.

Many doubts about Chen Yiming are just the instinct of experts out of technical confidence.

As for how to shoot the squirrel, which is invisible during the actual shooting, how to move the camera, and how to follow the focus, both of them are experts and there is no need for Chen Yiming to tell them.

This is just like a reporter asking how actors can act as actors during green screen shooting. It is a small problem that is difficult for those who don’t know how to do it, but not difficult for those who know how to do it.

If you're not too particular, an infrared transmitter, a pair of infrared glasses, and a few dozen dollars together can solve the problem.

In less than 5 minutes, Zhao Lu followed Xiangrui.

He was sweating all over from running. The zipper of his long down jacket was open, revealing the classic programmer skin underneath. He wore a plaid shirt with jeans.

The only thing that doesn't fit the coder's style is that he clearly looks to be in his thirties or forties, but his hair is still dark and thick.

After hearing Chen Yiming's request, Zhao Lu immediately assured that whether it was a CG squirrel or a "time-freezing" special effect, Boulder Workshop could get it.

Zhao Lu said that as long as there is no water environment or a background with too large a depth of field, "Freeze Time" can perfectly simulate it.

What needs to be simulated in today's scene is only the chassis of a truck and a temporary dirt road. The textures are not complicated. The camera position simulated by Sanpei just now has not even a few grasses in the viewfinder, so there is no problem at all.

As for the production of CG animals, technology has improved again last year, and the hair that was the most difficult thing to do in the past has been basically solved. However, this is a delicate job, which requires a lot of time and labor, and the cost is relatively high.

After listening to it, Sang Ping and Paul no longer had any objections to the modifications, and the new plan was finalized.

After adding "time freezing", this scene is equivalent to another hidden editing point. The so-called long shot opening is actually shot in three parts.

The first paragraph is from the squirrel to the truck, the second paragraph is from the truck to the driver, and the third paragraph is from the driver to the protagonist.

The three of them discussed it and decided to shoot in the order of 321, difficult first and then easy.

Because the first two segments are almost completely empty shots, there are no requirements for performance, but strict requirements for the scene; while the third segment is just the opposite, because it requires a large number of group performances, the requirements for performance are strict, and the scene only needs to ensure that there are no gangsters.

If the third segment is delayed, and it is delayed until the evening when there is a gust of wind or rain, the scene will probably be completely different the next day, and the first two segments will be shot in vain.

Chen Yiming's instructions were quickly conveyed to various departments through Li Mingliang, and the entire crew was running quickly.Following the instructions of Assistant Sang Ping, the engineering team that followed the team dug a trench that was 1/3 the length of the vehicle body and 1/4 the width of the vehicle body on the impoverished road.

Then, at the end of the trench in the direction of travel, dig a break line to lead the trench to one side of the dirt road.

This is the walking channel reserved for Paul.

Due to the addition of a low camera position, the camera cart could no longer be used and had to be mounted on a Steadicam.

Starting from the truck and entering the woods, until you reach the edge of the trench, there is the next editing point.

This will be a continuous "extremely" long shot, and Paul will have to move the camera nearly 100 meters.

After 15 minutes, all departments were ready.

Xiangrui held up the microphone and announced that the camera crew, recording crew, and all the actors were in place to go through the scene without any interruption.

Chen Yiming gave an order, and Sang Ping received the instructions through the earphones and began to operate the control keyboard to "shoot the squirrel."

According to Zhao Lu's professional advice, the squirrel's trajectory was chosen to be relatively easy to synthesize later, along tree branches, tree trunks, forest land and the center of the dirt road.

Sang Ping's first assistant was responsible for the infrared instructions. It was a rare opportunity for him to direct his boss, and his expression was quite eager to give it a try.

When the camera moved to the edge of the woods, Sang Ping's assistant issued an order. Soldier A, who was on standby in the truck behind the foot of the mountain in the distance, stepped on the accelerator, drove the liberation truck and turned around the foot of the mountain and rushed over.

The camera movement speed and the speed of the truck were tested and rehearsed in advance to ensure that the latter would just meet the squirrel at a speed of 45 kilometers per hour.

The vehicle speed was set based on Professor Sha's opinions. It was faster than the vehicle speed of our army's logistics units during the Peninsular War. However, considering the setting of the vehicle body being on fire, it was not exaggeratedly fast.

The squirrel was in position, the camera assistant gave the order again, the driver stepped on the brakes, and the old Jiefang groaned and slid and rubbed on the dirt road, leaving two conspicuous ruts.

Then, we crossed the photography ditch and stopped too far!
"Click!" Chen Yiming stopped directly.

The length of the ditch only leaves the driver with a margin equivalent to one tire diameter. Stopping too early or too late will cause Paul to be unable to move.

The drill is meaningless, start over!
The camera car and truck were reset, the stage manager directed the engineers to smooth out the ruts, and the second rehearsal began.

This time there were no further problems with the driver, and the truck stopped perfectly above the ditch.

He opened the door, jumped out of the car, twisted around and ran towards the back of the car.

Paul had already turned on the engine. He accurately caught the moment when the driver's feet coincided with the rear tires, firmly held the support rod with both hands and began to move laterally.

First move the lens, then pan. The lens attracts the driver's feet like a magnet, shifting the perspective to the side and rear of the car.

Soldier A followed Zhang Weining's instructions, turned around and jumped to the fender of the rear compartment. He stepped on the lower edge of the car with his right foot and grabbed the fender with both hands. Then he decisively let go and fell to the ground on all fours.

Xiangrui directly covered his eyes, and it looked like he had fallen hard this time!

Paul, who was closer, was unmoved. He seized the opportunity to push the mirror, and while holding the support rod steady, he hunched over and turned into the horizontal trench, stepping on the earthen steps to move to the ground.

At this time, Paul needs to move while adjusting the focus, and also needs to stabilize the relative position of the camera while changing his body posture.

Through the monitor, Chen Yiming could clearly observe the irregular shaking of the camera. It seemed that the focus was too much.

However, he didn't say "Ka", hoping to go through the entire process first to expose more potential problems.

On the other side, when the camera assistant sent instructions to the driver, Zhang Weining also received the signal at the same time.

When he saw the truck turning around the foot of the mountain, he directed the engineering group to charge toward the dirt road from the woods.

The timing of the appearance of the extras does not have to be as precise as the driver's braking, but it is only allowed to be slightly delayed by a few seconds. If it is any later, the taste of the rescue will not be right.

Paul finally left the ditch and stepped onto flat ground. He held the support rod in an arc and moved directly behind the truck. At the same time, he switched the camera to the driver's over-the-shoulder subjective perspective.

Behind him is his assistant, carrying other components of the F35B.

The second and third photography assistants followed and jumped out of the ditch. They carried a long cover like a stretcher and turned around to cover it on the ditch.

The cover plate just clicks into the grooves on both sides of the trench, and is buckled up to fit tightly. The upward side is painted the color of the dirt road. As long as it is not a close-up, there is no risk of it being worn.

The two assistants quickly moved away from the truck, and the extras just arrived and swarmed them.

(End of this chapter)