best camcorders zoom image
Q. My friend needs a "photo-taking device" for a trip she is taking. She's going to be photographing, but may be 300 ft away from them. Should she get a camera with high megapixels and less zoom than a camcorder, or a camcorder with high zoom and less megapixels? She is only allowed to take one?
Answer
my suggestion
go to yahoo shopping
digital cameras
digital camera GUIDE
be sure to check titles on the left side
the guide should answer your questions
my suggestion
go to yahoo shopping
digital cameras
digital camera GUIDE
be sure to check titles on the left side
the guide should answer your questions
Is it possible for a camcorder to have 100x optical zoom? Would it be possible to use even with a tripod?
Jake
My cousin has a camcorder with 70x optical zoom and it works fine.
I recently saw one that had 78x optical zoom, it was Panasonic.
Why do people say it wouldn't be possible to have 100x optical zoom?
78x optical zoom isn't that much less than 100x.
Answer
optical zoom over 20x is not very practical. megazoom is a result of using very tiny CCD imagers. for a 1/4 inch format CCD, the normal focal length is 4mm, 20x is 80mm which is 3 inches a rather reasonable size lens for a plam held camcorder. 100x would be 400mm or 15 inches, that is a lot of glass to hang in front of a 1 inch thick camera. then there is the problem of light gathering. for reasonable pictures in daylight, the lens needs a minimum iris opening of f4. the "f" factor is the ratio of focal length divided by lens diameter. so for 400mm to achieve f4 it would need to be 100mm diameter or 4 inches. But you might realize that the biggest problem is stability, to prevent blur, OIS is usable to 20x. That prevents blur but it does not control bounce or similar unintended movement, that is you will have sharp images of something that is bouncing. Here is where a tripod is needed. Television sports cameras use 40x to 50x lenses from Center field at baseball, or stadium top for football. But that camera is mounted on a $250,000 vibration supression mount, not a simple tripod. The megazoom may be something of value for still digital photos where the effective shutter speed can be increased to get a clear single frame. CCDs are getting down to 1/8th inch size with would reduce the example numbers in half. but then you have to cram the 12 elements used in a normal servo zoom (one that tracks focus) into minimum thickness of 2mm. that is why the flip cameras don't have optical zoom. and the funny thing is, all the sports people want to put "baby death" super fisheye lenses on their cameras, just the opposite of megazoom.
optical zoom over 20x is not very practical. megazoom is a result of using very tiny CCD imagers. for a 1/4 inch format CCD, the normal focal length is 4mm, 20x is 80mm which is 3 inches a rather reasonable size lens for a plam held camcorder. 100x would be 400mm or 15 inches, that is a lot of glass to hang in front of a 1 inch thick camera. then there is the problem of light gathering. for reasonable pictures in daylight, the lens needs a minimum iris opening of f4. the "f" factor is the ratio of focal length divided by lens diameter. so for 400mm to achieve f4 it would need to be 100mm diameter or 4 inches. But you might realize that the biggest problem is stability, to prevent blur, OIS is usable to 20x. That prevents blur but it does not control bounce or similar unintended movement, that is you will have sharp images of something that is bouncing. Here is where a tripod is needed. Television sports cameras use 40x to 50x lenses from Center field at baseball, or stadium top for football. But that camera is mounted on a $250,000 vibration supression mount, not a simple tripod. The megazoom may be something of value for still digital photos where the effective shutter speed can be increased to get a clear single frame. CCDs are getting down to 1/8th inch size with would reduce the example numbers in half. but then you have to cram the 12 elements used in a normal servo zoom (one that tracks focus) into minimum thickness of 2mm. that is why the flip cameras don't have optical zoom. and the funny thing is, all the sports people want to put "baby death" super fisheye lenses on their cameras, just the opposite of megazoom.
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