A high-speed camera is a device capable of capturing moving images with very low exposures and thereby creating frame rates in excess of 250 frames per second in the range of thousands of frames at different resolutions that can be set on modern day cameras.
A normal camera captures images at 24 or 25fps as set by television standards. It is a fact that there are events that happens lot faster than these standard frame rates. To see those events, changes, in between happenings we need to capture at the fastest possible frame rates.Modern technology on CMOS provides this break through with cameras available at thousands of frames capture speed.
Problem in high speed capture would be requirement of Light (as the capture happens in a very low exposure of the sensor) and also storage (to receive and store the frames or video in the same speed in storage devices). Watching the high speed while capturing is also an issue as display devices may not be capable to refresh at those frame rates.
Focusing the objects is also an issue as fast capture and play back from storage may not happen in real time to do focus or light adjustment in the high speed cameras.Most of the high speed cameras are provided with built in memory with proprietary or standard architecture to store the captured video and then play back. There are also RECORDERS with Solid State Hard drives to receive the video from high speed cameras and store them in compressed or uncompressed format for future use.
Most of the applications using high speed would be offline processing or viewing in slow motion to follow the phenomenon or take only the interested frames and work on. Obviously high speed camera capture would demand high power lighting and high intensity to capture with low exposure times. Many of the high speed cameras now provide an optional normal TV standard or VGA standard or HDMI or HDI outputs to view and do the focusing and all related adjustments before going to real capture scenario.The storage capacity in High Speed Cameras is limited to seconds or less than a minute.
This may be a bottleneck at times as the stored video would be over written if seconds are extended. To overcome these specialized high speed DVR s are available. This means the high speed cameras should provide an output that caters to a standard like 3G/HD SDI or GigE or Camera Link, USB 3 or Camera Link HS or Coaxpress . The DVRs are created to record real time and storage can be added according to the need of the time of recording. These DVRs will accommodate the maximum resolution and Frame rates supported by the above given standards.There is software available to capture these high speed video ( at a reasonable resolution and frame rates) to the PC memory and then dump the same into HDD of the host system.
Applications that require only 300 to 500 fps at resolution less than 1 megapixel or so can easily be accommodated in to this needless to say PC should have a high configuration of 16GB or more memory, Solid State Drives, i5 or above processor etc.High speed cameras are used in Scientific applications like Bubble analysis, track events involving fluid flow, air flow, learning about characteristics of tiny organisms that has high speed movement etc.
In defense ,tracking the missiles etc., in space tracking the rocket launch, in industries check quality at high speed in moving parts, detect flaws in machinery where parts move at high speed etc., in cinema and broadcast capture high speed movements in sports actions, wild life capture etc.PIV (Particle Image Velocimetry) is another application where high speed cameras find a place to capture events driven by Laser lights etc. We can see more on this PIV in our next coming blogs. Now, there are high speed cameras available with direct PCI Xpress connectivity to transfer the video captured at high speed directly to PC storage.