How to block the surveillance camera

1. If it is a radio, use a radio jammer.

2. If it is wired, it is a bit more troublesome. You must either cut the wire directly or use a relatively strong magnetic field to interfere with the wire.

Monitoring principle:

1. Use the monitor to control exposure

First adjust the monitor to a relatively standard state, and adjust this state at any time during shooting. The high-definition monitor has a waveform chart, which is very useful for controlling exposure and distinguishing details between light and dark parts. It has practical significance.

2. Automatic aperture control exposure

At this time, the automatic aperture is used as a light meter. The photographer must have a particularly clear understanding of the dynamic range curve of the surveillance camera.

3. Zebra crossing control exposure

Zebra crossing is usually specified at 90%-95% of the signal level. At present, high-definition surveillance cameras are designed with two levels of zebra pattern. The first level is set at 70%, which is 60%-65% of the 700 millivolt video signal level. The other is 100% zebra crossing, 70% corresponds to the gray area in the image, and 100% is the bright part.

In 2006, the number of movies shot with digital equipment reached 110, accounting for 1/3 of the country's total production. The technical differences between digital movies and film movies in actual shooting are mainly differences in tone, tone, exposure control, etc. The shooting process is also different.

The exposure link of digital movies. Lens - Spectroscopic filter - CCD - A/D analog-to-digital conversion - Black spot correction - Gain adjustment - White balance - Stray light correction - Detail adjustment - Color array - Inflection point adjustment - GMA adjustment - White cut and black cut. Film film is controlled by a light meter. Some digital photographers also use light meters. Generally, digital cameras have equivalent sensitivity. For SONYF900, at 3200K color temperature, shutter speed 1/48 second, and 24P mode, it is equivalent to 320 degrees. Light meters are rarely used in digital cinema because light meters are set based on the photosensitive characteristics of the film emulsion. Film is more sensitive to blue light and ultraviolet light, but unlike film, digital is relatively sensitive to red light.