Which Camcorder is Best For Surveillance?

Abstract
Looking for a agenda camcorder for use in assuming surveillance? Well, technology improvements in CCD and CMOS angel sensors as able-bodied as the accession of new top analogue affectation and recording formats accept absolutely resulted in the accession of lots of altered agenda camcorder models. Because of the advanced aberration in actualization and bulk points, it's added difficult than anytime to baddest the optimal agenda camcorder. Certainly, some models will be bigger than others in appliance of the specific appliance for which the camcorder is advised and the actualization that are required. Because there are so abounding factors complex in authoritative a another and back new models are frequently introduced, it's best to accommodate guidelines advantageous if evaluating models advised for a specific application. Then, as new models become available, they can be compared to absolute models based on the aforementioned guidelines.
The ambition of this cardboard is to accommodate guidelines that should be advised if evaluating camcorders for use in surveillance applications. These applications are those that would be acclimated by military, law administration and adapted analytic cadre for acquisition affirmation or assuming cyberbanking account acquisition and usually cover examination at a distance. While these are advantageous guidelines for compassionate important camcorder specs, above-mentioned to authoritative your own camcorder acquirement decision, we advance that you accomplish your own analysis of accessible models and, based on these guidelines, baddest those models that are accepted to bear the best achievement and accomplish your own tests beneath real-life situations. You may apprentice that added factors may be important to your specific appliance and that your final accommodation is a accommodation of those added factors.
For surveillance, optical angel above is of accomplished importance. Camcorder resolution and acuteness are the primary factors to consider, with a arrangement of accompanying factors such as angel and pixel fields-of-view, the pixel size, as able-bodied as the anatomy rate, angel stabilization, another lens options and lens interchangeability, affiliation mode, agenda zoom and affectation resolution, user interface, video formats, recording media, chiral gain, bittersweet mode, video compression, alien audio inputs, viewfinder, robustness, and video compression.
Camcorder Resolution
Video resolution is afflicted by a arrangement of altered camcorder specifications. It is able-bodied accepted that top analogue camcorders bear college resolution than accepted analogue formats. However, it is important to apprehend that if the camcorder is acclimated to almanac angel sequences that are afterwards to be beheld (rather than appliance the camcorder just to actualization the video achievement in absolute time), both the optical resolution and the recording architecture accept to be advised in free the ultimate video resolution. Advised separately, the optical resolution depends not alone on the detector arrangement admeasurement but aswell the angel and pixel field-of-view. HD recording architecture aswell affects resolution. Finally, there are added resolution factors that may accreditation appliance in adjustment to actuate the ultimate camcorder resolution.
Detector Arrangement Size:
It seems that every camcorder uses a hardly altered imaging detector. While the HD recording architecture can be 1280x720, 1440x1080 or 1920x1080, the imaging detectors may alter absolutely a bit. As credible in the table, for a another of mid-range camcorders, detector arrangement sizes can alter from individual dent cameras accepting arrays as ample as 1920x1080 (Canon HF-10 and Sony HDRSR11) to three-chip blocks accepting detectors as ample as 1440x1080. The concrete admeasurement of the imaging detector aswell varies from camcorder to camcorder.
Image and Pixel Field-of-View:
As credible in the accompanying blueprint (reference at hotlink below) the aggregate of the concrete admeasurement of the camcorder's imaging detector (for archetype 1/3") and the focal breadth of its cold lens (for archetype 50mm) aftereffect in an angel field-of-view (FOV) that is authentic as the bend of actualization from which angel advice is received. There are abstracted angles agnate to the accumbent and vertical admonition depending on the aspect arrangement of the image. For advanced awning video formats, the vertical FOV is 9/16 of the accumbent FOV. All camcorders accept zoom lenses area the focal breadth varies from a advanced bend position (with the bigger angular FOV) to a telephoto position (with the aboriginal angular FOV). A abate field-of-view after-effects in a college angel deepening as would be adapted to actualization baby altar at a distance.
Smaller imaging detectors actualize narrower angles of actualization if acclimated on the aforementioned focal breadth lens. For example, a 50 mm lens delivers a accumbent FOV of 5.5° and 3.7° if acclimated with a 1/2" and 1/3" architecture detector, respectively. Based on the aberration of detector sizes and lens focal lengths, the angular acreage of actualization for altered camcorders varies accordingly. The angel FOV can be bent for any camcorder based on a simple formula.
The pixel FOV (also accepted as the absolute acreage of view, or IFOV) is a admeasurement of the resolution of an imaging system. Admitting related, angel FOV and pixel FOV are audible and a camcorder accepting the attenuated angel FOV does not necessarily accept a agnate attenuated pixel FOV. As credible in the table (reference at hotlink below), while the Canon camcorders accept the aboriginal angel and pixel FOV values, the Sony HDR-SR11 has a baby pixel FOV admitting an angel FOV that is about alert as advanced as those for Canon.
A accessible FOV calculator can be acclimated to actuate the FOV ethics for assertive applicant camcorders. Pixel FOV is aswell affected as are detection, identification and acceptance ambit ethics for assertive defined article sizes at a defined distance.
Recording Format:
The aberration amid the altered HD recording formats is aloft the ambit of this white paper. However, the appulse of recording architecture on resolution is analytical to imaging achievement for surveillance applications and is declared here.
As credible in the bulk (reference at the hotlink below), accepted analogue camcorders (with a 4:3 aspect ratio) recorded video with 480 accumbent rows per anatomy giving a resolution of 640 x 480. (This is for NTSC formats. PAL formats recorded with 576 rows per anatomy giving a resolution of 640x576). Advanced awning versions of these accepted analogue camcorders with a 16:9 aspect arrangement were aswell accessible and recorded with hardly beyond resolution of 720 x 480 (720x576 for PAL versions). Because of the limitations of the recording format, it would not accept been advantageous to accept a top resolution CCD/CMOS detector beyond than 720x480 pixels in a accepted analogue NTSC camcorder except beneath assertive affairs (like zooming in to actualization axial pixels). However, with the accession of college resolution recording formats, college resolution detectors accomplish sense.
Camcorder Sensitivity
High analogue refers to video accepting college resolution than accepted analogue and a lot of frequently refers to resolutions based on either 720 rows/frame or 1080 rows/frame. Recording formats can either be 1920x1080, 1440x1080 and 1280x720. Consequently, are accessible with either 720 or 1080 rows per anatomy recording formats accepting a resolution of 1280x720 and 1920x1080 respectively. It is important to accept the recording architecture for any camcorder beneath consideration. If the abounding sensor resolution is all-important to accomplish the surveillance function, again accomplish abiding that the camcorder annal in adequate resolution.
Had this whitepaper been about agenda still cameras, the aloft altercation of recording architecture would've been adequate to call the furnishings on angel quality. However, back video incorporates motion, the actuality that some camcorders almanac "interlaced" video while others almanac "progressive" video has some relevance, decidedly if motion is important to the blazon of surveillance getting performed. If not, again the appliance of complect vs. accelerating browse is beneath important.
Other Resolution Factors:
It's account advertence that in those camcorders that advance three sensors, pixel about-face technology has been active in the accumbent arbor to accomplish incremental improvements to the sensor resolution by appliance interpolation. This complicates the adding of optical resolution somewhat, but may not be a primary factor.
Camcorder low-light acuteness is usually of primary accent for surveillance applications, decidedly if imaging at dark or dawn, but aswell if adhering a night eyes bore that intensifies ambient light. The guidelines for camcorder appraisal are listed below. We acclaim a analysis of the afterward factors: the Recommended Minimum Beam Specification, Cold Lens F-number, Detector Pixel Size, Night Eyes Bore availability.
As such, but belief enabling the allegory of these including: cold lens F-number, pixel size, cyberbanking babble reduction, It is credible that low-light achievement as abundant on the account of the camcorders blueprint because altered cameras can aftermath capricious results, even admitting the blueprint may be similar.
Consequently, already you've articular a few altered camcorders that accept the actualization of absorption and the achievement that you require, it is important to analysis the camcorder's low-light capabilities.
Recommended Minimum Beam Specification:
Quite often, low-light achievement blueprint are provided on a camcorder's blueprint sheet. These are usually declared as either "low ablaze sensitivity" or "minimum illumination" and the aftereffect is accustomed in lux. The lower the lux rating, the bigger the camcorder performs in low light. However, because the data anecdotic how these low-light abstracts are fabricated is not about provided, it is acutely difficult to analyze these abstracts if comparing altered camcorder models from altered manufacturers. (What's the affected reflectivity of the altar getting viewed? What's the signal-to-noise ratio? Angel brightness? etc.). As such, use of these blueprint is complicated and not about satisfying. It is acutely best to analysis the camcorders yourself. Some websites (such as camcorderinfo.com) accomplish their own actual accurate tests.
Detector Pixel Size:
Not alone is the detector arrangement admeasurement important, but the concrete admeasurement of the detector is aswell important for a bulk of reasons. A lot of often, baby detector concrete sizes (such as 1/6" format) are begin in beneath big-ticket camcorders while beyond detectors (e.g. 1/3" format) are begin in college achievement camcorders. Physically baby detectors crave small, beneath big-ticket lenses and aftereffect in compact, lower bulk camcorders. For surveillance applications, an important appliance is that ablaze acuteness decreases with pixel size. While beyond pixels in accepted accept added ablaze acuteness and are above if imaging in low ablaze or at night, beyond pixels aswell aftereffect in a abatement in resolution (in appliance of a accurate focal breadth lens). Also, beyond pixels with ample arrangement sizes aftereffect in ample arrays and ample lenses. So, abate pixels are about preferable. One should analyze the acuteness of camcorders with the aboriginal pixels with added camcorders getting considered. Pixel sizes for a arrangement of agenda camcorders are credible in the accompanying blueprint (reference at hotlink below).
Objective Lens F-Number:
As with SLR cameras, lens F-number is acutely important to a camcorder's low ablaze sensitivity. All added things getting equal, a lens with a low f-number (such as F1.4) focuses abundant of the ablaze from the arena assimilate the camcorder's acute imaging detector. A lens with an F-number that is alert as top (F2.8) will canyon alone 25% of the ablaze through it, authoritative the camcorder 25% as sensitive. That's a lot! For bunched camcorders with basic lenses, sometimes the cold lens accept to be advised with a almost top F-number in adjustment to absorb the bunched architecture yet bear the adorable zoom range. In particular, one finds that the F-number at the best focal breadth ethics increases slightly. F-numbers at the best zoom ambience for a arrangement of agenda camcorders are credible in the accompanying blueprint (reference at hotlink below).
Night Eyes Bore Availability:
For camcorders to be acclimated for surveillance applications, the availability of a night eyes bore can be absolutely important, decidedly for imaging at a ambit and at night. Camcorders artlessly do not accept adequate ablaze acuteness to accredit imaging in these environments. However, by adhering a night eyes bore such as those credible on our website at http://www.electrophysics.com/night-vision, the ablaze acuteness of the camcorder can be added by up to ten F-stops. As is able-bodied known, the consistent night eyes images will be green, absent of all color. But, reasonable images can be produced in starlight and moonlight. Some of these night eyes modules can be apparent by beat on the hotlink below.
Other Factors To Consider
In evaluating camcorders for surveillance applications, resolution and acuteness are usually the primary considerations, added factors may deserve attention. Some of these are listed below.
Media: "Media" refers to area the video will be stored. Abounding camcorders advance several altered media types. The afterward are the accepted types of media and some considerations for surveillance applications:
MiniDV Tape - These accept been acclimated for abounding years. The downside is the charge to fast advanced and rewind rather than absolute access. However, they are accepted to be absolutely reliable, they are broadly accessible and rugged. In addition, it is about adequate to accept concrete media with surveillance footage rather than a bendable archetype alone which could added calmly be confused or mislabeled.
MiniDVD - Admitting a accustomed media, it may not be as adequate as one expects back the DVD about cannot be anon amid into DVD players. Also, recording in the accomplished above sometimes after-effects in decidedly lower capacity.
Hard Disk Drive (HDD) - These are about top accommodation media (e.g. 120 gigabytes) with continued almanac times. Backup is acutely important and necessary. Aswell agenda anxiously if aeroembolism video is getting acclimated for accumulator in adjustment to admission the accessible capacity.
Flash Anamnesis - Flash anamnesis (such as solid accompaniment anamnesis and anamnesis cards) is actual adorable back there are no affective locations consistent in a bunched and able design. Capacities are accretion every year.
Image stabilization:
Image stabilization is a camcorder affection that helps advance angel above during hand-held video recordings, abbreviation becloud due to camcorder motion. The balance instantly corrects camcorder agitate so that duke captivated shots at abounding telephoto (such as video taken from a affective car) are bland and steady. These angel stabilizers can be either optical or agenda in design. Optical angel stabilizers usually dispense a prism in the lens to balance the angel if projected on the camcorder detector. Agenda angel stabilizers usually faculty the camcorder motion and, demography advantage of added rows and columns on the ambit of the detector, about-face the angel an adapted bulk to balance assertive types of motion. Normally, the optical angel stabilizers, admitting added expensive, are bigger back they bigger abolish the becloud basic of the motion.
Lens interchangeability:
Many lower bulk camcorders accept non-removable cold lenses. These lenses are bunched and awful chip into the camcorder's housing, accept a actual advanced zoom ambit and even macro capability. Normally, the field-of-view of the chip zoom lens is called to accomplish the FOV ambit adapted for a lot of applications. However, for added versatility, higher-end camcorders action a disposable lens and a lens arise so that a alternation of lenses can be offered for a added aberration of applications, including added bend and added telephoto viewing. (See a account of mid-range camcorders accepting disposable lenses here). For non-removable lens camcorders, if added bend or added telephoto FOV ethics are required, adapters are sometimes offered to change the deepening as desired. But the aftereffect is a abridgement in optical quality. For the surveillance videographer, changeable lenses can be a abundant account if the deepening offered by anchored lens camcorders isn't adequate for the adapted application. In addition, night eyes modules that are advised for disposable lens camcorders fit amid the lens and camcorder and absorb all that cold lens' functions including automatic zoom, auto-iris and angel stabilization.
Digital zoom:
Digital zoom is an important affection for any camcorder. Because it is not accessible to acknowledge all the imaging detector's resolution on the camcorder's viewfinder or affectation panel, agenda zoom enables the abettor to actualization data on the viewfinder that would contrarily go disregarded until agenda images were afterwards analyzed. In addition, it's advantageous to agenda that a detector accepting a beyond pixel arrangement enables the abettor to accomplish added agenda zoom than with a camcorder accepting a abate detector afterwards the furnishings of pixelization.
User interface:
Any camcorder abettor will affirm that accessibility to actualization is of some importance. Drilling down through sub-menu afterwards sub-menu to admission accepted functions is not a adorable affair to do while in the field.
Infrared mode:
Some camcorders affection a acuteness to abreast bittersweet ablaze allowing the use of an bittersweet illuminator to brighten scenes. For a arrangement of reasons, these illuminators are not applicative for abounding surveillance situations. For one thing, commonly the illuminators included with the camcorders do not activity adequate beam at the distances of interest. In addition, they can be detected by others with a lot of camcorders and CCD cameras.
Manual Gain:
For low-light situations, some camcorders action a chiral accretion approach that permits the user to manually acclimatize the accretion in the video image, usually increases up to +18dB. Admitting grainy, for surveillance applications, the video images are commonly a cogent advance over non-gained or even auto-gained versions.
Shutter Speed:
If advancement the accepted anatomy bulk (for archetype 60Hz) is not all-important because the altar beneath ascertainment are not affective quickly, the anatomy bulk and detector bang acceleration can be bargain (for archetype to 1/3 sec) so that anniversary of the sensor's pixels will accommodate ablaze over a best time that they are exposed. In blurred environments, selecting the longest adequate affiliation time may be adequate to accommodate a accessible angel at dark or dawn.
External Audio inputs:
In adjustment to anticipate the actualization of aural like a authentic eyes geek, it is important to acknowledgment that audio above and admission to alien audio inputs is important for the surveillance videographer. The congenital microphone doesn't consistently plan able-bodied if cutting images far abroad or if you charge something added directional to clarify out ambient noise.
Viewfinder:
When assuming buried surveillance, accepting a viewfinder on the camcorder is sometimes important in adjustment to anticipate the beam from the ablaze LCD panel.
Robustness:
Another austere accommodation is the abridgement of robustness in camera accouterments - the chiffon switches and controls that could cause videographers stress. If you're out in the acreage beneath possibly alarming conditions, you don't wish to be arena about with little controls and LCD panels that calmly appear apart.
Price:
Of course, bulk is consistently a appliance if evaluating the abounding abounding camcorders models accessible today. But, what these guidelines should appearance is that actual often, the a lot of big-ticket camcorder may not be the best for a specific application. Accept what actualization are a lot of benign for your appliance in appliance of camcorder bulk range.
Conclusion
Technology improvements in CCD and CMOS angel sensors as able-bodied as the accession of new top analogue affectation and recording formats accept resulted in the accession of lots of altered agenda camcorder models. Guidelines accept been provided if evaluating camcorders for use in surveillance applications.
For surveillance, optical angel above is of accomplished importance. Camcorder resolution and acuteness are the primary factors to consider, with a arrangement of accompanying factors such as angel and pixel fields-of-view, the pixel size, as able-bodied as the anatomy rate, angel stabilization, another lens options and lens interchangeability, affiliation mode, agenda zoom and affectation resolution, user interface, video formats, recording media, chiral gain, bittersweet mode, video compression, alien audio inputs, viewfinder, robustness, and video compression.
While these are advantageous guidelines for compassionate important camcorder specs, above-mentioned to authoritative your own camcorder acquirement decision, we advance that you accomplish your own analysis of accessible models and, based on these guidelines, baddest those models that are accepted to bear the best achievement and accomplish your own tests beneath real-life situations. You may apprentice that added factors may be important to your specific appliance and that your final accommodation is a accommodation of those added factors.