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1/4" CCD Single chip
3.6mm-72mm zoom F 1.4
NP series battery
1 pound 15 oz with battery
8mm CCD camcorder
The CCD imagers used in most of today's camcorders, are naturally sensitive to I.R., but most electronics manufacturers see this as a disadvantage, rather than a feature. In part, this is because we do not ordinarily see infrared, and this changes the relative brightness, and color of the recorded scene, giving it an unnatural look. Infrared, also has a different point of focus than visible light, and it's detection will give an image a blurry look. The usual solution for this problem is to add an infrared filter to the filter pack. CCD units do not react, even to visible colors, in the same way that our eyes do, so all CCD equipped cameras (including still cameras) have a filter pack over the sensor to compensate. Sony has taken advantage of the infrared sensitivity of The CCD imagers in it's camcorders, to introduce it's Nightshot system. Though this is trumpeted as a new feature, it is a potential common to all CCD imaging units.
When Nightshot is activated, the camera removes the I.R. filter from the filter pack. It also opens the aperture all the way, and sets the shutter speed to a constant 1/60th of a second. This is great for night scenes, though it makes shooting infrared for effect, difficult during the day. Filters, or pinholes could be used for daylight shooting, though the best approach is to disable the fixed shutter speed. I will not explain how to do this, because I wish to be responsible for no ruined camcorders (other than, possibly, my own). Suffice it to say that, for those with the skills and the interest, the modifications required may be found on the web. With Nightshot activated, the scene is rendered in a green monochrome. This is similar to the look of a scene in a classic NVD, and a Sony camcorder, with the Nightshot system activated, can probably be thought of as the equal of a gen0 (WWII era) NVD. The Sony Nightshot units have built in infrared light sources, effective out to about thirty feet (the claimed distance is ten feet). More powerful, external I.R. lights are available.
One interesting thing I noticed, is that the Sony units are more sensitive to I.R. than my first generation night scope, though the camcorder is nowhere near as sensitive to visible light. This would make the Sony unit a better I.R. unit, than a first generation scope out to the range of the I.R. source, though a first generation NVD scope would continue to be a better, general purpose unit. This only applies to the first generation NVD's; the second and third generation units vastly out perform the Sony units, even in I.R. sensitivity. Even the first generation scopes will vastly out perform the Sony units, if no I.R. source is used. Of course, the Sony units have a built in I.R. source, located at the front of the unit, just under the microphone. I made the comparison between my first generation Safari unit, and the Sony TR517. The comparison was completely subjective. I simply looked through both units with an external I.R. source, and noted that the picture in the Sony unit seemed brighter. With the I.R. source switched of, and the built in I.R. illuminator of the Sony blocked, The camcorder screen went blank, while the view through the Safari dimmed somewhat, but was still clear enough to be usable. The Sony unit is rated at 4 lux, for visible light, while most gen 1 NVD scopes are rated at about .05 lux. Some second and third generation NVD's are rated at .001 lux, and below.
The CCD unit in the Nightshot cameras, is able to detect Infrared emanations down to about 1cm. This is standard performance for infra red scopes. The Sony scopes, in common with NVD units, can not really detect thermal radiation. Thermal image units are able to detect radiation down to about 3 cm. It is possible to get some thermal imaging out of these sensors, but an object needs to be nearly red hot for it to be emanating in the 1cm band. There are some myths surrounding these units though. One of these is the "X-Ray" vision, said to be possible, when proper I.R. only filters are used. There is some basis in fact here, but the cameras may have to be modified in order to get this effect. It is said that certain models are able to see through clothes, by detecting the infrared reflection, and radiation given off by the human body. This is due, in part, to the fact that certain types of cloth are somewhat transparent to 1cm radiation. This is actually possible with certain older models, but only works with the proper filter in place, and the camera modified somewhat so that the auto exposure is still active during Nightshot shooting. This "feature" will not work at all on the newer models; they have had their filtration packs modified.
Virtually the entire line of Sony camcorders uses the same CCD sensor, filter pack, and Nightshot system. This is a 1/4" sensor, with 460,000 pixels of resolution, or a 1/6" CCD with 270,000 pixels. Generally, only 250,000 of these pixels are recorded on the image, whichever CCD unit is employed. The other pixels are used to stabilize the image. Though Sony states that the sensors can record images under 0 lux of illumination, this is only with an infrared light source. To record by ambient light, 4 lux, the actual sensitivity of the sensor, are required. One of the features of the series is the hybrid optical/digital zoom. These can give zoom ratios of 300-400, or more. The problem with this is that at the higher zooms, the images can be very pixelated.
My particular unit is the bottom of the line TR-517. This is a Hi-8 unit, which is what Sony now calls it's line of analog camcorders. The Hi-8 designation indicates somewhat increased resolution over the earlier versions of their cameras. Sony calls this system XR (Extended Resolution). I can find no exact specs on how much more clarity or resolution this new system has over the old one; it is simply stated as being "improved". The camera has, what have become, all of the standard features. These include titling, a variety of AE settings, autofocus, fader, and some special effects. There are also the options to use manual exposure, and manual focus.
Without supplemental lighting, the Nightshot is not really good at any
distance outdoors. It is probabaly at it's best inside of dimly lit places, or at very close range outside. The two photos shown here are captures of a Night shot being used indoors. They are both taken down a dark hallway. One is with Night shot on, the other is with it off. For use outside, a good I.R. light based upon a high intensity flood, or an efficient diode array would seem to be recomended.