How to choose the right camera
So which camera to choose for a certain application? It is clear that the thermo vision cameras have their special applications while
the high-speed cameras are used to acquire short triggered snapshots where we need extreme video rates to capture crashes,
explosions, and other fast events.
The decision between a good camcorder and a medium speed camera is not that easy. The main difference between these types of
cameras and the high-speed ones is that with the medium and low-speed cameras we can continuously store video stream to the
disk until we run out of disk space. We can also use software triggering on the video to reduce the amount of data or perform the
online compression.
However, the system needs to have a good performance to stream video. We will need high-performance hard disks and a very well
built system, as we might still run to the limit of performance. We have to know that the typical VGA size image takes 300 kB. If we
have 100 frames per second, we need to store 30 MB/s for one camera.
Clearly, if we want to make a high-speed video, we need to use either
.
has a slightly higher speed (120 FPS in VGA).
compresses the picture in camera and we can achieve 600 FPS in VGA mode.
A big advantage of both camera types is that they can be triggered from the analog card and therefore the data and video are
perfectly consisted. If 25 or 30 pictures per second are enough, we might consider using a camcorder. I would suggest progressive
scan cameras, so as not to have interlaced pictures. Web cameras are usually low price/low speed/low quality but are an extremely
helpful tool to document the experiment. We had lots of feedback from customers telling us that a simple, even poor picture helped
them to understand the recorded data much better.
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