CctvCameras

TableOfContents CctvTemp

ConexantBt878

Spectral response limits
* http://tinyurl.com/6fx963 0.003Lux from http://www.wateccameras.com and http://www.supercircuits.com is the limit in lux sensitivity for surveillance purposes. The values higher than this are used in astronomy (0.0001lux) and can't be used with moving objects since it smears the picture. http://www.wateccameras.com and http://www.supercircuits.com are the preferred suppliers of high sensitive lux cameras. Adverts for CCTV cameras are deceptive, they will state that for night time vision in the presence of InfraRedLeds the CCD camera has a sensitivity of  0lux. There is no such thing as 0.0000000000000......0000lux. We have the following without IR illumination: * 0.5 lux on 1/4 inch sensors * 0.1 lux on 1/4 inch sensors which is also limit for color images * 0.01 lux on 1/3inch sensors B/W * 0.003 lux CCD limit before image smearing takes place on 1/2 inch CCD sensors with movement. B/W * 0.0001 lux used in AstronomyCameras  because the night sky is static. The larger the CCD sensor the higher the sensitivity and cost of the camera. Only BW are available at 0.003lux. UavInTheNews uses 0.003 lux camera for aerial monitoring. A CCTV brochure must state the lux sensitivity (0 lux is not true) and image sensor size. The more sensitive ranges of lux requires less InfraRedLeds to illuminate a dark area.

Build own analogue camera
Reverse engineer Sanyo and others via http://www.bomarc.org/catalogs/Catalog-upload/VIDEO.txt BoMarc and build own CCTV camera and sell via FrontingCompany. http://www.dspfpga.com/?lang=en design with Sony CCD sensors.

FSO and cameras
Digitize the video signal as the camera source and transmit the signal back via FreeSpaceOptics instead of  using a VideoBalun. Nearly unlimited repeater nodes are created with FSO. Use FSO to repeat a camera signal back to the base.

CCTV stops crime in Natal
http://www.saweather.co.za/frameset.html?furl=http://www.iol.co.za/widgets/rss_redirect.php?artid=vn20080105083058569C443360&setid=1&sectid=13&url=iol&vne=0&csect=South+Africa

Lenses used in CCTV
* OpticalManufacturers

Build pan, tilt, Zoom system with RS485
["RS485"]. RS485 under ElecTronics to control stepper motor manipulating camera on roof. Use InfraRedLeds to provide nightvision at over 300m in pitch black darkness between 880 and 940nm.

Spectral response and CCD sizes
The larger the CCD sensor the better the spectral response or the better image resolution is achieved. 1/2'' CCD coupled with an Infra-red laser can detect motion at 800m. 1/3'' provides a good trade-off between cost and performance. 1/4inch, 1/3 and 1/2inch are sizes used for night vision. The lux value must be at least 0.01lux for long distance vision.

Astronomy cameras for CCTV
* South African distributor of http://www.wateccameras.com: Scientific Alert 011 476 5718 * http://www.ultech.co.za

* 0.003lux camera * 0.08lux camera * See AstronomyCameras

Forums
* http://www.cctvforum.com/archive/post/video_over_Power_over_ethernet-9452-17.html * http://books.google.co.za/books?id=DaQY8CrmqFcC&pg=PA278&lpg=PA278&dq=%22analogue+video+to+ethernet%22&source=web&ots=PVOq4dWsJb&sig=LjCxYzpf7myaikQfUhnmQHcJ-o4&hl=en&sa=X&oi=book_result&resnum=76&ct=result

pulnix
http://www.pulnix.com/Defense/Defense1.htm

Pulnix has UltraViolet sensitive cameras.

Nightvision
Nightvision for CCD are achieved in the 820-880nm(semi-covert) and 940nm(completely covert) pectrum. A cluster of high power InfraRedLeds(820nm) will glow like red dragon eyes. For street surveillance 940nm must be used which is completely invisable to the human eye. The diodes are more expensive and the spectral response of the CCD must sensitive in the 940nm region. To prevent headlights from blinding the camera a IR filter lens is attached. Discriminating between a human walking down the street and a car driving past is possible. See http://www.zoneminder.com wiki for details on this. Eyes of animals work as the same way like CCTV Cameraswhile in the dark.

http://www.baxall.com sells a camera with an A/D converter on every pixel of the CCD sensor. The camera is usually used to attenuate sharp light overloading the CCD sensor. http://www.reditron.co.za will be able to provide more info on the Baxall range. http://www.axis.com Ethernet camera's CCD sensor are not suitable for nightvision applications. A high end mini-itx connected to a KMC-4400r or Pico capture card should be used and the mini-itx Ethernet port connected to the network. http://ffmpeg.mplayerhq.hu are used by ZoneMinder to stream Jpeg images over the network. In this way an Axis ethernet camera functionality is simulated. For a high current(2A, 12v) long range IR camera like the E-558(eaglecctv) use a standard PC power supply. Bridge the Green and Black contacts on the ATX connector to power it up.

CCD sensors
http://www.amazon.com/gp/product/0521648343/qid=1149096194/sr=1-10/ref=sr_1_10/002-9750372-8694448?s=books&v=glance&n=283155

http://www.amazon.com/New-CCD-Astronomy-Capture-Backyard/dp/0971123705/ref=pd_sim_b_4/105-3424817-3677210?ie=UTF8&qid=1149096194&sr=1-10

1/4, 1/3, 1/2 inch Ccd's
In the days of vcr's we all used to use wither vhs (240 tvl colour) or svhs (supossidly >400tvl) and cameras were either med res (380 tvl b/w/330 colour) or high res (570 tvl b/w 480 tvl colour). Now as you could only resolve 240 on vhs why use high res cameras? Well you do end up with a slightly sharper image from high res kit even though your only recording the same actual number of pixels, i assume its to do withthe way the camera makes 380 tvl source into a 625 tvl transmission but i dont know. I would say always go for high res where possible (on the cam front)

Note on format sizes 1/4 1/3 and 1/2 inch ccd's all have (or can have) the same number of pixels. As most cctv is made from camcorder chips we tend to follow that industry, thats why the really specilist cctv are so much money (1/2 frame transfers etc). Even though a 1/4" can produce the same number of pixels a 1/2" chip can it needs a lot more light or gain to be able to do this. This is why cheapo cams have leds on them as they use 1/4 pickups and through their own light rather than 1/2 which can use clear starlight. Id go with a 1/3 as its a good balance between cost and low light performance. But if you have the light it matters little. Plus the smaller factors need cheaper lenses so you can save there.

Protecting the CCTV camera against sabotage
PIR detectors are protected from having the heat sensing unit spray painted with black paint by using a short range Ultra-Sonic detector to detect any attempt as masking the PIR. See ElecTronics. It is known in the trade as PIR anti-masking. Clamp such an Ultra-Sonic detector against the camera to determine if a thief spray paints the camera. This is especially useful if the camera is not in motion detection mode.

Via Mini-itx and megapixel-camera
from http://robots.net/article/2153.htmlBR * http://www.c-o-n-e.org/acone/software.html * http://www.c-o-n-e.org/acone/hardware.html Pictures of thermal regulated camera box.

Commercial DVR
* $200 http://www.gadspot.com/product_info.php?&products_id=84 * $4 VGA converter http://www.gadspot.com/product_info.php?products_id=100&osCsid=bcda1909ab55e091277b97685723b340

Build own Ethernet cameras
Build a circuit based on CircuitCellar June 2007 issue of video analogue to digital conversion using ARM processor and H-V line syncroniser seperator. Using an ASIC ciruit the digital data interfaces with an embedded ethernet controler which in turn interfaces with a switch. The switch connects to the VDSL2+ DsLam modem for video surveillance network.

Lenses
LENSES FOR CAMERAS $59 * http://store.yahoo.com/discountsonline/min35afzooml.html

ELECTRONIC HEARING OF GUNSHOT. * http://cbs2chicago.com/illinois/IL--ElectronicEars-in/resources_news_html

Nightvision goggles for R1000 * http://www.opticsplanet.net/nightvision.html

Video surveillance specialists * http://www.activesolutions.com/ * http://www.globalcomputer.com/applications/searchtools/search.asp?mnf=509&cat=35

* OGG THEORA Elphel Model 333 A Linux-based network camera that uses the Ogg Theora decoder, implemented on an FPGA in open source code. Ogg Theora is said to allow, for the first time, both a low bitrate and high-resolution, high-framerate video. details. http://linuxdevices.com/articles/AT3888835064.html http://www.elphel.com/3fhlo/samples/333_samples/

MPEG4 linux boards from the aviosys website * http://www.vitecmm.com/product.php?id=2

Video streaming * www.icecast.org * www.asterix.org? spelt right?

Other notes
* CctvRetailers * CctvLinks