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jisaac

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Everything posted by jisaac

  1. jisaac

    Extreme Ex80 examples

    the last 2 are ex40mnx
  2. Have you guys ever heard of this? We put in a system for a location here in little rock. And the customer got a cable internet. The upload stream is 850k. Well I was having a problem with just a few cameras locking up and having real bad latency. So I talked to a service guy and he was saying that their upload stream is right at 5.mhz which is the same as the cameras. And that it was interfering with the upload. ?
  3. those of you who use filters when adjusting cameras during the day which do use welders glass or neutral density filters? And which kind do use welders glass- #? neutral density- x?
  4. We did an install for a residential and he also wanted a video doorphone on his front door. So we installed the aiphone jb2md and the jb2hd and jb2a http://www.aiphone.com/Product_Pages/Current_Products/JB.htm So after we get done with the install he ask if the doorbell was wired in to his old doorbell system. Apperiantly he wanted the new bell from the video doorphone to ring over his old doorbell systems whole house speakers. ( Great!@!$%%@! ) The jb series runs the video and doorbell over 1 pair of speaker wire. Can anyone figure out how I can do this? I need to somehow get the new bell of the aiphone jb2a to ring out over the old speakers. Anyone know?
  5. jisaac

    1/4" UNC plastic screw

    do you mean nylon screws
  6. jisaac

    welders glass or neutral density

    I have liked the neutral density filters. although they are significantly more expensive. Especially when you drop them.
  7. jisaac

    Need Help Picking a Camera

    how far are you looking at for IR? And what degree beam are you needing?
  8. your right he did get into his own little world there for a little bit before bouncing in and out of reality. And I probably could have shortened it. But the thing that was in favor of cut and pasting the article was the fact that it was already typed out and I was out of my adderall (add medicine). And if I made a post without my adderall in me you would really be confused!!!
  9. I know there has been several post about resolution mismatch. What happeans when you have a high res camera but a low res monitor. Or Low Res camera with a high res monitor. And several other related questions. Well I found this. Its an article by charlie price. Thought it might be helpful ----------ARTICLE--------------------------------------------------------------- Dear Charlie, Is there an advantage of using a high resolution (570 lines) camera with a time lapse recorder that has a resolution of 300 lines?. In other words, would the recorded image from a 570 line camera be higher quality than a 380 line camera? How does the video recorder interpolate or "compress?" the higher res image into a lower res image? Is it similar to audio where a higher quality source makes a better recording than a lower quality source, even though the limitation of the recording device may be less than the higher quality source? Thanks for your help. Just sign me "Losing lines in MO" Dear lines After all the hub-bub that is made about resolution, what is this phenomenon that we keep telling you is so important to the video image? More importantly, what is the real affect of high or low resolution images in our security applications? I mean, we all know, or have heard, that you should use a higher resolution camera outside, or for long shots, but why? In the end, does it really matter what style of camera we use? Actually it does, but not necessarily for the reasons that you have been thinking or lead to believe. First let us describe and define resolution. There are several ways to measure the resolution of an image. You can use the actual number of horizontal lines used to manufacture the image (horizontal resolution), pixel resolution, or vertical resolution. To understand any of the different resolutions, we must first go back to the basics. First, how is the video image recreated on the monitor screen? Don't run, this sounds highly technical, but we can break it down to simple terms. To give an image the illusion of motion, we flash a series of fixed pictures on the screen at a rate that is faster than the human eye can detect. Each fixed scene is incremented slightly farther ahead in the action than the one before it. When we put the image on the screen, we don't just flash up a picture, we paint the image one line at a time. This line of video information is painted on the screen from the left side of the monitor to the right and is referred to as a horizontal scan line. We first go down the entire screen painting only the odd lines, then we repeat the process filling in the even lines of information. This process is referred to as two to one (2/1) interface. In the end, we create a total of sixty (60) half images (fields) or thirty (30) frames per second (US) or fifty (50) fields / twenty five (25) frames in countries using 50 Hz power. The total sum of these lines create what we refer to as the vertical resolution of the image. I realize that this seems somewhat confusing, but vertical line resolution refers to the total number of horizontal lines. This is because we are counting the individual lines of information from top to bottom or vertically. Leave it to an engineer to make life confusing. In the US, Canada and many other parts of the world, we work under NTSC (National Television Standards Committee) standards which fixes the video image at sixty (60) fields per second and 525 vertical line resolution (525/60). In Western Europe, Australia, parts of Africa, and the Middle East, they work with PAL (Phase Alternating Line) format which fixes the video image at fifty (50) fields per second and 625 vertical line resolution (50/625). But how do we paint an image on the screen? What magic could possibly exist that gives us the ability to make an image? It's really very simple. If you have ever pushed your face close enough to a monitor or television screen, you have seen rows of independent bright spots. These little spots are referred to as pixel points. In the end, a video or television image is nothing more than a collection of variously shaded pixel points. The total sum of these pixel points on the screen is referred to as the Pixel resolution. The total number of vertical columns of the pixel points (counted from side to side) is referred to as the Horizontal resolution. This is because we are counting from left to right or horizontally. Again, just a little confusing, but par for the course. The horizontal resolution is determined first by the camera, second by the transmission method, thirdly by the weakest link in your video system. The combination of vertical and horizontal lines create an overall format resolution that will determine the quality of the image. Since the vertical resolution is fixed at either 525 lines (NTSC) or 625 lines (PAL), we depend upon the horizontal resolution to determine or define our image quality. Imagine the entire video image on the screen as nothing more than a drawing made on a grid paper. The smaller the squares, the more defined the lines in your drawing can be. Consequently, the more lines used to make the grid, the smaller the squares. Now, to the heart of the matter. The first lesson to remember is that the overall quality or resolution of your image will only be as good as the weakest link in your video system. Consequently, there is a lot of money being spent on high resolution equipment, but the results are coming out equivalent to lower resolution images. For example; the average nine inch (9") black and white video monitor will reproduce, up to, six hundred lines of horizontal resolution. As a quick note, the average television only produces three hundred and twenty five lines of horizontal resolution, which is why a video monitor almost always looks better than a television. Now, let's say that we have a camera that produces an image with eight hundred lines of horizontal resolution. Will the monitor make the eight hundred line image or will it drop off two hundred lines of resolution somewhere and reproduce an image of six hundred line quality? Answer, drop off two hundred lines of resolution and reproduce an image of six hundred line quality. In retrospect, what if we had a camera that manufactured an image of three hundred lines of horizontal resolution. Would the monitor reproduce at six hundred lines? Answer, no. In the end, the monitor is an idiot box with no ability to recreate what wasn't there in the first place. The monitor however, is seldom the problem. Consider that the average video recorder, used in today's surveillance video systems, only has a reproduction capability of an average of three hundred and twenty five (325) to four hundred and eighty (480) lines of horizontal resolution in the playback mode. "But, my monitor has six hundred (600) line capability and I bought a special camera, for a small fortune, that has eight hundred (800) line horizontal resolution!" Oh well, now you know why your video playback is never as good as the image on the screen. Figures, doesn't it. You thought that you had a problem with your video recorder and have just come to find out that you really do. You spent too much money on a camera that the VCR cannot emulate. You have however, also just learned another key reason for using professional, industrial video recorders instead of the two or three hundred dollar consumer units that you buy at the store. It's really simple if you know just one more thing and that is that your television only has three hundred twenty five (325) line horizontal resolution. Therefore consumer recorders are not going to be built at such a level as to produce more resolution than the television can. One place where we need to use higher resolution cameras is outside. This is because the majority of our outside cameras are using longer than usual lenses (more telephoto) and are usually on longer cable runs. Since we can loose resolution or quality of image by looking through telephoto lenses, and we can loose resolution on long cable runs, we prefer to stick with higher resolution cameras up front. Think about it. If the image is going to loose resolution, before it hits the CCD (Charged Coupled Devise), or because of the cable run, wouldn't it make sense to have as much of this stuff as possible? Absolutely! But this isn't the sole or even the most important reason for using the high resolution cameras. OK it's time to get to the meat of the situation. Assume that our position is one of security and that we need to identify various objects or individuals on a video screen. Also assume that we will be doing this from two perspectives. The first perspective is while looking at the screen on the monitor with a direct feed from the camera and the second is during the playback of the image off of the video recorder. For the first example, I will use a camera with a horizontal resolution of six hundred lines (a really, really good one). I am looking at a six foot man and he fills my screen from top to bottom, head to feet. So we can say that our image resolution is about five hundred and seventy (570) lines (assuming a 5% lose due to cable and lens). This is good, however, what is the amount of resolution that we can use for the identification of the person from a facial perspective? Five hundred and seventy lines? No, in fact the average human head (face) takes up only one fifth (1/5) of the overall body. Therefore the true resolution of the mans face is only one fifth of five hundred and seventy lines or roughly, one hundred and fifteen (115) lines. This is still a huge amount of video information and so we will be able to make a solid identification of the individual (provided that lighting and angle of view are adequate). On the backside however, let's say that we are now looking at the play back of our time-lapse video recorder. We have the same man, same scene, same amount of scale and size. The difference here however is that our recorder only has three hundred and twenty five (325) lines of resolution at play back. Now what is the true resolution of the man's face? One fifth (1/5) of three hundred and twenty five or about sixty five (65) line resolution. Still very good and easy to identify, so we're OK. For the second look, let's drop the man's overall appearance in the scene from taking up the whole screen into a little more realistic attitude. Let's make the man one inch (1") tall on an eleven inch screen (11")(as measured diagonally). This would mean that his whole body takes up about one sixth (1/6) of the overall screen. What is the overall resolution of the man this time (assuming the same scenario as described above). For his overall body, we would take one sixth of five hundred and seventy (570) lines of resolution or we would say that his body had ninety five (95) line resolution. His face would be one fifth (1/5) of that or nineteen (19) lines of resolution. Getting low, but we should still be able to identify this individual. Now let's go to the playback at three hundred and twenty five line resolution and take another look. Our first calculation says that the man's body uses one sixth of the overall scene for a total of fifty four (54) lines of resolution. His face is one fifth (1/5) of that or roughly ten (10) lines of resolution. Probably still enough for identification purposes, but certainly pushing the envelope. On the other hand, what if we needed to identify something about this man in specific to make our case.... say his shoes. His feet would represent about six inches of overall identifiable surface area in real life. If we reduce this to screen size, we could say that the top surface area of his shoes (assuming we have an elevated angle of view looking down at the man) would represent about one third (1/3) of the same amount of area that his face did. Therefore, we would have roughly three and one half (3.5) lines of resolution, on playback to use for shoe identification. It would not be enough to make a case. At this point, you may be saying that I am going too far and that a man's shoes is not a good basis for an example. I would wager that you make this statement based upon the lack of believe that such is evidence. However, think back to O.J. Simpson... were not his shoes of some question because of the bloody trail? Several weeks ago, I was involved with an FBI case where they were trying to prove guilt of a man based upon a video tape playback and the nature of his shoes in particular. This man had entered into a large retail store, was dressed in a black coat, black pants, black pullover stocking cap (not that unlikely in Iowa in the winter) and black shoes with some sort of white markings on the top. Turned out to be white doves on top of his shoes and they were the ones he was arrested in. The problem came in the playback of the video that captured his image during the robbery. When I first saw the image, it was played back via a consumer recorder on a color television. His shoes were defined by about two lines of resolution and the doves appeared to be something related to what a dove might leave on your shoulder. Played back on a proper industrial recorder and with a black and white monitor however, his shoes in fact had a full six lines of resolution and the doves stood out like an accusation. In the end, resolution of an image is much more than just how many lines we use to paint the screen. It relates to the overall screen, relative size of the object of identification, and the type of equipment that the image is recorded or even played back on. This is what resolution really means to you in the field. Therefore when you design your systems, keep in mind that the size of an object in perspective to the overall size of the scene is also relative to how many lines of horizontal resolution will be available to describe the object. The smaller the object of identification, the higher the camera resolution will need to be. The larger, less defined the object of view, the lower the overall resolution can be. Keep in mind however, that it is the weakest link of your system (usually the recorder playback) that will be the most important thing in the end.
  10. by the way I went with your suggestion and it worked great! Exactly what I was looking for. I appreciate it.
  11. I am not sure where to post this but here is my issue I need some help. I am working on designing a system for a high end residential. And this guy wants on this one side of his house a outdoor motion detector that will play a pre recorded message when it detects motion. Can anyone let me know of how to do this and what equipment.
  12. jisaac

    Hello All

    dont feel bad.....I dont know anything. Welcome to forum.
  13. jisaac

    Small IR Camera Suggestions?

    How much money are you willing to spend? inexspenive to one person may be expensive to another. I think extreme's ex40mnx are not expensive. But some people are think that 1,200 dollars for a camera is outragous. unless you give a $ amount your willing to spend then your going to get responses that are based on what that persons idea of "inexpsensive" is.
  14. jisaac

    Extreme WZ20

    hey rory, so you got a chance to test out the 484 with external IR? Not bad huh? Ya that is an excellent combination. I have a customer who got 2 sets of ex82 and panasonic 484's on his house looking at the same shot just because he liked both so much.
  15. jisaac

    Panasonic WV-CW244S

    In addition to my last post I also have some of the Panasonic WV-CW244S Vandal Proof High Resolution Varifocal domes here is the link http://catalog2.panasonic.com/webapp/wcs/stores/servlet/ModelDetail?storeId=11201&catalogId=13051&itemId=97189&catGroupId=14474&surfModel=WV-CW244S/22&displayTab=F I will be completely honest and tell to you that these are not good for areas that have low light at night. As they are not day night cameras. The military mostly have fully lit areas that these were being put in at. So they worked great there. How much am I asking? I will let you make an offer. I am not trying to make anything off of these just get them off my hands for as much as I can to pay for my cost. Hey something is better than nothing at all. So try me I might just let go of it for very very little. So if you need some vp high res domes for a excellent price then call me at work 5017534801 or email me at isaac@arksurveillance.com dont pm me as I never check those
  16. I have a bunch of equipment for a military job that never was. So I have a never opened dedicated micros 16 channel digital sprite 2 with 500G internal hard drive. this is the exact model number DS-2ADX16C-500GB Like I said this has never been used or even opened. Just need to get rid of the equipment from that job. So I am asking only $3,800.00 for this dvr. And if your a dealer and interested you can call me at my work number 501-753-4801 or isaac@arksurveillance.com dont pm me as I never check those.
  17. here is an example of a fujinon day/night lens that was put on a cheap cheap cheap camera that was suppose to be a temporary camera for the weekend. this camera right here is an old mace cam 37 (kandcorp and matt remember those). These were retailing for about 110 about 2 years ago. notice not much shift in focus even though the light level around the whole room drastically reduced. so those lens do make the cheap cameras look decent. although they do catch a glare pretty easy. anyone notice that?
  18. the fujinon aspherical lens is a day night. they dont make on thats not.
  19. you do have to take in consideration your application. there is a place for the 1.4 lens also. Granted we use them rarily they can be usefull in a situation that has very bright parts of the day in which your luminance level can be an extremely large amount. Putting in a 1.4 can help with your image getting to bright. Usually you can predict that in designing the system but sometimes you did not know about a certain time of the day that creates a problem. But in general the 1.0 and similar are your best bet. The day/nigth lens have exceptional performance with little shift of focus from night to day. The back focus is pretty easy to do with those. kandcorp, if you use a neutral density filter when setting up your camera you will get better performance out of any lens inside or outside. and yes your change in lenses will improve your night sensitivity. I would highly recommend the fujinon d/n aspherical lens. The are extremely easy to adjust. Back focus ring is easy to get your fingers around and manuevor. plus they are not that expensive. pretty cheap if you ask me.
  20. jisaac

    High-Definition CCTV

    thats what I say. Not about this system but every system. Screw the cheap systems because you can loose your tail end on a cheap system with little profit very very fast.
  21. jisaac

    Speco vs Bosch

    definitly give us the exact model numbers and specs provided. Because although in a bosch vs. speco head to head match bosh would win; the best speco vs the worst bosh camera might be a different story. But in all preliminary thoughts i would say bosch is your winner
  22. jisaac

    City wide Wi-Fi Yipeee!

    ya they offer that over here in north little rock its called unsecured wireless networks!
  23. jisaac

    EX82 Examples

    2 different cameras. 2 different focal lengths nice option
  24. jisaac

    WDR Camera

    gotta love those pelco housings. The only thing about them though is the fact that you have to hold the top of the housing with some resistance because of the way it is spring loaded. So your sitting there trying to get the camera adjusted while keeping the front of the housing out of the camera view. its tricky. oh ya while also holding a welders glass in front of it.
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