Probably every major and self-respecting company is constantly improving its security system. One of the best decisions in this regard are the surveillance cameras. Today, the market of optical cameras to monitor the premises or area abounds with a large range, in this case, you should pay attention to the type of camera.
The most common today are the monochrome camera, put it in simple language the camera with black and white optics. Clear that these cells perceive and transmit a signal video images in two basic colors: black and white. At first glance, this seems out of date, since there are already cameras with color recording. However, the monochrome video surveillance cameras, there is one positive, and perhaps most important nuance. Black and white CCTV cameras have a tendency to perceive the invisible infrared radiation that can produce high-quality photography, both in daylight and at night. Color cameras also do not possess such a property in night scenes are almost useless.
So it turns out that the choice of surveillance cameras, you should pay, especially for its intended use. If you are going to rent some space or territory only during daytime, the color analog video camera will be quite convenient for you. Otherwise, if necessary round the clock surveillance is to acquire monochrome camera.
четверг, 25 марта 2010 г.
How to choose filters for the camera
Filter represents a device that is the most common
variant is screwed to the front lens and the lens is used to
obtain various effects, or to retain or any range
light waves (color, UV), or for a proportional reduction
transmitted light (ND - neutral density), or to exclude light
waves of a certain polarization (polarization).
Filter - UV (HAZE) or SKY
First of all, it is mechanical protection of the lens. In this case, the filter - a piece of
glass cost 20-50 dollars can practically "save" the lens, which
expensive it in 10-20-30 times. In addition, the filter can be without fear of damage
wipe the lens, it protects against dirt, dust and spray the object itself. It
has a serious plus, because without a filter to protect against dust, splashing
lens have to close the lid all the time. What speed does not
adds.
Use a UV filter or SKY as a permanent portable and has a protective
sense and the fact that these filters eliminate the maintenance of color balance in
blue when shooting in bright sunlight and in other situations. Human eye
unlike the film is not sensitive to UV radiation and the part does not see this blue.
Detaining UV radiation filters to remove excess cold-blue flowers from
frame.
Mitigation (vague) filters
Produced under different names (soft, mist, foggy, etc.). Softens
image, making it slightly blurry. Lower contrast. Very useful when
portraits and landscapes of the morning, especially in the lateral or posterolateral
illumination. These filters are divided by the intensity of weak, medium and strong.
Since no standard, different manufacturers of their own ideas about the power
impact. So choose the best filters in the presence "of their
camcorder. It is recommended to pay attention to the options for low and medium
graduation, as a strong "fog" in the frame is not always pleasant.
Shaded filters
This filter, in which part of the area (about half) is colored
neutral gray or any color dye, and the other - net. Gray
shaded filters help to get a more spectacular image when shooting
landscapes where pritemnyayut sky. Red or orange filter will be shaded
very useful when shooting stunning sunsets.
Polarizing filter
In bright sun and cloudless sky, this filter appreciably pritemnyaet "sky
makes it dark blue. In conjunction with snow or sea view it looks
great. In addition, the polarizing filter eliminates most of the glare
water, glass and other glossy non-metallic surfaces. This allows
see through the camera what the naked eye can not see because of
strong reflections. For example, the river bottom under the water surface covered with shallow
ripples, or the dummy behind the glass display cases, which reflects the whole street.
The polarizer also "extinguishes" flashing on the grass, leaves, trees, and some
fruit, whose color is pure and saturated, as the promotional pictures.
Try to remove sunlit oranges or tomatoes through a polarizing
filter and without it - and you will feel the difference!
"Star" filters
allow to obtain the luminous rays from all the bright objects. Differ
mainly the number of those same rays. Night streets with lanterns and illuminated
advertising, the candle on the table, highlight on a glass of champagne - it's just "Musi-pusi"
some! But quickly bored. So, buying a "star" - not
overuse.
"Spectral" filters
also operate mainly in the brightest parts of the image, making them
radiate "rainbow" or "halo". Very impressive. But bored even faster than
asterisk.
So much talk about filters. The following discussion focuses on the more serious
optical nozzles.
Wide nozzle (wide angle)
expanding field of view lens. Being in a confined space, not
very easy to shoot interiors or group of people. Even when fully
opened zoom frame is one or one and a half man. And to
take action, the operator has to constantly "throw" the camera with a
character to another. All this leads to unnecessary fuss. Image obtained
"antsy" and uninteresting. In general, SHU-nozzle can be useful when traveling
on a cruise ship or a train, in museums, guided tours through the narrow streets
European or eastern cities and even thousands of similar situations.
Wide angle to distinguish the relative width of the frame without it, the width of the frame with
such. The lower this ratio - the better. 0.7 - is not bad, 0.6 --
ok. 0.45 - too much, give the effect of so-called "fish eyes", but in
some cases is very good. For example, try to avoid the subject
a circle, imitating circled the camera - very helpful, reducing almost twice
yaw angle camera in the hands of the operator, and visually by the same increasing
radius of the trajectory of an imaginary camera.
Telenasadka
But if you want to visit the safari park or other place where there
opportunity to see interesting animals and birds, then you, first of all, you
think about buying telenasadki the lens of your camera. This detail
allows to increase the maximum amount of the zoom lens has a 1,7-2 times. A
is when shooting animals, when close to an object is difficult or impossible,
very well worth it. By telenasadke you may have to purchase more and
hood - the lens device that limits the penetration of solar skew
rays on the front lens cap.
When shooting with telenasadkoy, however, the situation is not as easy as working with
"wide angle". Videolyubitel Everyone knows that at the maximum "hitting"
picture becomes unstable. Image Stabilizer, even very good,
not very helpful. And when worn telenasadke stability will be even less.
Watch this "movie" is simply impossible. One way out - use a tripod.
Anamorphic attachments
In many cells, if we want to get an image format 16х9,
image is obtained by a simple truncation of the upper and lower fields. In addition to narrowing
angle of view is further loss of clarity. Anamorphic attachments
help get rid of this loss, allowing the horizontal cover more
wide angle, just needed to ensure that images captured in
frame format 4x3 installation mounting project 16х9 gave the correct
proportions of the picture. Immediately warned: (1) These nozzles are very expensive. (2)
Many cameras have installed in the viewfinder for a nozzle. So
putting on and removing the nozzle anamorphic format 3x4 (and should be removed from such
attachment) you'll see in the viewfinder flattened laterally picture.
All the stories about the deterioration of picture quality due to additional "noise" in
optical system are mainly attributed to the days long past, when there was no
available technology complex enlightenment to the modern glass and cheap
crafts, which are made of is not the best glass with bubbles and often do not have
enlightenment, or have a one-sided illumination, and that poor-quality,
which is easily destroyed. It advocates a second opinion is often
oriented to advice, made almost in the pre-war literature or
domestic sources, which are oriented to the domestic same level
quality and technology of manufacturing of filters and optics.
When selecting a filter you should trust the products of companies
B + W, Tiffen, Hoya, brand filters such as Canon, Pentax, Nikon or
Minolta. Not bad to make sure that before you is not fake. It happens so rarely,
but mention it is. It is quite easy, but in such cases is
make purchases in stores that have a large assortment of filters.
The only filter, even in a beautiful box, but anyone who has not
Also known as better not to buy. Also, you should pay attention to packaging,
accuracy of manufacturing and other external signs, such as the right
spelling of the name of the company. Filter, especially UV or polarizing,
desirable to have a multilayer coating, which is often called
MC-MultiCoating.
In general, in my opinion, a good filter "verified" the company does not worsen
image quality so much that it was possible to see at all. Therefore
I recommend all fans (pro yourself will understand what's what), along with the lens
acquire and filter - UV or SKY. When buying always look like
nozzle behaves on your camera, some on the market quality
very low.
Article about a webcam in the newspaper "Evening Moscow"
In nature, you can watch without leaving home.
Modern web cameras allow to observe the animals directly from home.
Screams are heard from the room: grunt, Ryki ... Frightened mum opened the door.
But do not worry - it just went wild boars. At trough gathered for dinner the whole flock. Pigs less pushing each other at the trough and slurp loudly with pleasure. Leader pushes impudent young. Effect of full. Like a movie, but the momentary happening completely changes the experience. It was like she was sitting in an ambush. And now my back knocking the drop, and my feet get wet ...
Hide and seek with the rabbits
Modern technology allows you to travel around the world without leaving home. For you have trampled all paths other researchers: biologists, zoologists, meteorologists and just lovers of nature.
They found the camera in a bird's nest in the zoo, on submerged reefs. You just turn on your computer, go to the desired page, sit comfortably in a chair - and watch "a movie about zverushek. For example, watch for Strix in the nest or the elephants, that's just now reaching to the stream.
Webcams are different. Some show "live video". Picture me with such frequency that you will not notice the frame. Picture clear, sounds are transmitted with virtually no distortion.
There are cameras, where image is changed less frequently: every 30 seconds, every minute or even once every 6 hours (web camera, fixing a solar flare). Sound can be absent altogether. But the look is no less interesting. After using the camera can see what else you do not see at all. That right now there was a surge in solar activity. And the camera mounted on the satellite, captured rushed to the side of the Earth prominence.
There are controlled chamber. Clicking on the button on the keyboard, you can move the image left and right, zoom in or remote.
Control the camera in the aviary with the rabbits like playing hide and seek. You - driving, and you need to find a crouching animal. After a couple of minutes to search and it appears that the rabbit calmly chewing a carrot in the cage (it will show other web-camera), in his cage and was not released.
Night camera or set in dark places (eg in clusters) operate in the infrared mode. If instead of the image on the screen black, it does not necessarily mean that the apparatus had broken down. Check the time zone, suddenly at the end of the world overnight?
Internet star has become a mother
White stripes-glare - Somewhere near the camera in a hollow tree spider weaves a web. On sparse bed of feathers lay an egg and a little startled several light lumps. Clara lives here, the owl of the genus Strix. The man who invented her name, is lost in the pages of the forum monitors Estonian website "Calendar of Nature.
In the diary of events you can see that on the first day of spring Clara laid an egg. A week later, there were already five.
At first Clara was an exemplary mother, a long absent herself from the nest, leaving eggs in the cold at night without supervision. Condemnatory posts on the forum owl forced to think again: it is densely sat on the eggs and practically ceased to fly out of the hollow.
A fortnight ago there was a tragedy. Marten climbed into the slot and took the egg. But the remaining four - survived. Last week, a forum zapestrel joyful message: "Our web-Star became a mother." Hatched sovyat Claire hides from the audience, obscures its wings as a hen-hen.
On the existence of webcams Clara, apparently unaware. It is worth it to talk (sitting at home in front of the monitor), as Clara immediately turns his head and looks directly at you eye-saucers.
Monitor Strix want round the clock.
The problem is that the owls - night bird, and you in the morning - at work.
The whole world in the palm
- I was amazed how much you can see in real time: the animal world, different cities and countries, - says Denis Trofimov, creator of the site www.geocam.ruTo date, perhaps the most complete directory in RuNet webcams. - I started collecting interesting links.
When they have accumulated too much, decided to organize data and make a site.
Site a little over a year. But in the catalog are more than 1000 webcams placed throughout the world. More than 4 thousand people stare per day on the site. Denis every day testing the camera. Special program tells how long have not been tested. If it is interrupted, it is noted.
Why does the camera stop working? In a powerful online channel and the associated hardware needed money. And often all rests on the enthusiasm. Webcams steal, break, with them have accidents. Last year in New Zealand at the camera because of the hurricane tree fell.
The volcano Etna equipment flooded by lava.
- And that in general can be seen through a webcam, without leaving home? - I inquire.
- Yes, the whole world! - Sure Denis. - From the simplest microscope laboratory of the Washington Zoo to the planet Earth from space. You can see the Eiffel Tower in Paris, the Vatican, Kizhi, the Pantheon in Rome, Mecca, home of Santa Claus in Lapland, the Milan Cathedral ...
Webcams - not just entertainment. There are of them and the real benefits. Window into the nature of the child may be interested in geography, biology, astronomy. And an adult can easily find out what the weather at the resorts, and receive a lot of other useful information.
For many people, cameras on the Internet - the only opportunity to see distant lands, or, conversely, to return to the places they are associated with memories. "I look at the Czech Republic, where she lived before. Can you add the camera Orenburg? This is my home "- asked one of the visitors copyright.
According to statistics, the most popular webcams, of course, those who shoot animals. Among them is the constant "windows of nature, and there are seasonal (for example, in the nests of storks). By the way, now is the time to watch storks. They just arrived.
Help "BM"
The first ever webcam was launched in 1991, showed the coffee in one of the rooms at Cambridge University (lazy IT staff wanted to know, not over whether the coffee on the floor above, before climbing behind him). She worked until 22 August 2001 The last photograph made this camera can still be seen on its home page on the Internet.
вторник, 23 марта 2010 г.
Camera products
The best security camera system products are
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