protech90 0 Posted November 10, 2010 D1 resolution is (704x480), A 520 Line Camera is (720x480) providing the DVR with as much resolution as the cards can capture. Question is, if we use 600 and now 700 Line cameras will the image improve on a DVR capturing at D1? Thanks, Kevin Bell Share this post Link to post Share on other sites
rory 0 Posted November 10, 2010 D1 is 720x480. 704x480 is cropped D1 or 4CIF. Some DVRs will crop D1 to 704x480, it is said there are sometimes 8 pixels on each side that are unusable. This is what I have read at least, and come across with a few various DVRs. What I have noticed is that with some camera chips there will be black edges either on one side or both or the top or bottom. Figure it must be a codec issue with the DVRs, this is common with Geovision, also Dahua, so I imagine there are many others. However on the Dahua for example, even at 704x480 and least 1 black edge still exists on at least one camera I tested. I would like to know more about this particular issue if anyone is more knowledgeable in that area. Strangly it is normally only in recorded or networked video, or saved images, hence it must be an encoding issue with the DVR? Otherwise I guess we have to wait until the DVR software or firmware is updated to support the new resolution. Is this going to happen? Not sure, as most high res cameras, 480-650TVL, are already 768x494 effective pixels and yet we are still using 4CIF or D1. What above D1 though, I did notice a 16CIF, but then that would be too much for these cameras. I guess i need to sit down and read this one day: http://www.itu.int/rec/T-REC-H.261-199303-I/en On that same note, I keep getting slammed with emails from the same companies in China about their 700TVL cameras .. LOL. In fact just now I got 2, 1 of them from the same company that already sent me a couple emails earlier on! The prices are still very low also, but more expensive than their other cameras, well only by like $30, hey its china. Share this post Link to post Share on other sites
protech90 0 Posted November 10, 2010 Question is.. can we expect a better image quality (live &or Recorded) by using 600~700 Line Resolution cameras vs. 540~550 Line? Is provided more pixels than needed help? Share this post Link to post Share on other sites
rory 0 Posted November 10, 2010 Regarding 700TVL, Probably not. Its like using a 520TVL camera and recording at CIF. Still only get CIF quality. But Id have to hold off from being able to say that with certainty until I test or see one in action in a real world application. 600TVL i use all the time now, but they are still just the same total effective pixels of say a 550TVL camera. Dont notice any real difference besides many of them have other features that make them better in some cases. Share this post Link to post Share on other sites
protech90 0 Posted November 10, 2010 Thanks for the reply.. I have some 600 and 700 Line cameras coming.. I'll try it out and advise. Share this post Link to post Share on other sites
SEANHAWG 1 Posted November 10, 2010 Just Curious, What is the typical resolution capabilties of a CRT TV. Not a CCTV monitor, Just a regular CRT TV. I am sure there are variances but what was the typical resolution before the LCD's took over. It seems that we get better rez out of small 13-19" CRT TV's than we do LCD, Plasma TV's and/or computer monitors when dealing with Security Cameras. Share this post Link to post Share on other sites
protech90 0 Posted November 11, 2010 Just Curious, What is the typical resolution capabilties of a CRT TV. Not a CCTV monitor, Just a regular CRT TV. I am sure there are variances but what was the typical resolution before the LCD's took over. It seems that we get better rez out of small 13-19" CRT TV's than we do LCD, Plasma TV's and/or computer monitors when dealing with Security Cameras. I'm not sure what the resolution of the CRT's was.. but, I do know (size) is relative to the image clarity re: 13~19" monitors show a great image vs a large screen 42" etc.. Share this post Link to post Share on other sites
cglaeser 0 Posted November 11, 2010 I do know (size) is relative to the image clarity re: 13~19" monitors show a great image vs a large screen 42" etc.. How far are you sitting from each monitor? Do you adjust your viewing distance based on screen size? If so, the images will appear more similar. However, if you view both monitors from the same distance, well of course, the smaller monitor will appear to have sharper image. The images on my iPhone are so tack sharp they will draw blood. Best, Christopher Share this post Link to post Share on other sites
