But if the camera was looking along the street, not side to it, this car would be moving towards or away from the camera, and its motion wouldn't be so rapid. The car driving 100km/h is a very fast object. So another question is, what is the best setting for recognizing people, cars, plate numbers ect.? It all depends on what lens you have (wide or tele) and what scene you are looking at. Basically, setting SHUTTER parameter is always a compromise between image clarity and motion blur. At shorter exposures noise starts to creep in, but there is less motion blur. The longer the exposure, the less noisy the image is but also more prone to motion blur. At 1/30s the image sensor will grab 100 times more light than at 1/3000s. If so, than why not setting the camera to 1/100000s exposure for all time? Because reducing exposure time also reduces amount of light available for the camera.
At 1/3000s it should be almost perfectly sharp. If you change shutter speed to 1/300s, the car will move by 10cm and so there will be much less blurriness. This whole meter of motion will be captured by the camera on a single image and so the car will look like blurry trail. During 1/30s time, the vehicle will move by almost 1meter. Now imagine a car doing 100km/h (62mph), perpendicularly to the axis of your camera. And so, at night NTSC cam will use 1/30s exp., PAL will use 1/25s exp. If there is no such frame rate available, it will use its highest frame rate, like 15fps or 20fps. By default all NTSC cameras are set to 30fps, while PAL ones to 25fps. This sentence is true only when considering longest available exposure for a given framerate.Īt factory settings your camera will use shutter speed as slow as possible dictated by framerate. I'm mentioning this, because once I've seen a thread, where a person claimed that the more fps you have in your camera the sharper the image will be. This is by the way one and only relation between framerate and shutter speed. If you use slower shutter, you will lose framerate. So there is no way to use longer exposure than 1/30s at 30fps. If you multiply 1/30s by 30fps you get exactly 1s. In this example 1/30s is the longest exposure available, because we've set a frame rate to 30. This is what is called the exposure time (in camera settings it is called SHUTTER). It can "look" at the scene for as long as 1/30 second or as short as 1/100000s. For simplicity it can be described like this: for every frame the camera "looks" at the scene through the lens and saves the image. If you set its frame rate to 30 frames per second (fps), it captures 30 images per second which are then combined into a video file. Your camera captures a given amount of frames (images) every second.
Motion blur is a result of exposure time (shutter speed) being too long in respect to motion of an object. The image looks great on factory settings, but all moving objects at night are blurry and I can't identify anything." Leaving factory settings is not a good idea. Many times on this forum I've seen posts like: "I bought a set of cameras recently. This is probably the most common issue, new camera owners run into.
Shutter encoder gif how to#
1.Here is a quick guide to what might go wrong with the image of your cctv camera, and how to fix this.
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