aurmol

but 1/2.8" vs 1/3" with mere difference of 1/0.2" is almost insignificant. I think dahua sensors are all 16:9. In their 1.3Mp and 3Mp models 4:3 sensors. It's like dahua just cut the sides. This occurs to both 1.3Mp and 3.0Mp in all models at 3.6mm at mere 72 degrees field of view. Only the 1080p 2Mp dahua ip cams are wider at 88 degrees... the 16 degrees of difference can't be caused by the mere difference between 1/2.8" vs 1/3" sensor.. would it?

It's like they used 1080p or 16:9 sensor and just cut the sides. This occurs to both 1.3Mp and 3.0Mp in all models at 3.6mm. Only the 1080p 2Mp dahua ip cams are wider at 88 degrees... There is one exception to the 1.3Mp though. Their 2.8mm model didn't cut the sides of 16:9 sensor.. instead they increase the top and bottom to get much larger vertical to make it 4:3 but at cost of big barrel distortion. This is why i'm stuck with 1080p.. as it is the only widest with 88 degree fields of view.

Definitely different, though that may be due to the different sensor or a different vendor for the 3.6mm lens. Is the bottom image the 4300S? It doesn't look that good compared to the top image, and part of it appears to be the lens quality... I'll measure the FOV when mine arrives - hopefully any day now. Here are the FOV measurements on the 4300S. 3MP, 1.3MP, D1 = 72 degrees HFOV, 53 VFOV 1080P, 720P = 67 degrees HFOV, 37 degrees VFOV SXGA = 67 degrees HFOV, 53 degrees VFOV The Dahua website lists 97.6 degrees HFOV for this lens. Hard to say how they could be that far off, but this is Dahua. The marketing people probably used an FOV calculator; hopefully the engineers didn't give them this data. I'll post more detail in another thread when I've got some time to check it out more, but it looks like it's not that big an improvement over the 3300 series. It still appears to have the over-soft shadow compression, but it's been cloudy for days, so no chance to check thoroughly. Likewise, day/night switching is still unreliable (though the IR is controlled by software now). Mine came with 2.210.0000.2.R, build : 2013-08-21, and there's a newer version - 20130911, so I'll update it first before doing any extensive testing. Buellwinkle. Have you checked the 4200S, the 1080p version of the 4300S? The 4200S uses the sony exmor sensor and it has 88 angle of view versus the 4300S 72 degrees. Note the 67 degree you mentioned is when one sets the 1080p resolution in the 3mp 4300S. So how does the 4200S compares to the older 3200S? The wider 88 degrees of the 1080 4200S has significantly more angle than the 3mp 4300S.

So why is cvi more faded than ip.. is it because the ip has better compression or because of the cheaper cvi lens or because of some losses in the cable? Now for sake of discussion if the cable was merely 1 meter and highest quality.. would it still be faded?

my runs is only 10 meters... SDI is better in live view because it is pure raw data to your monitor without H.264 compression.. whereas when you view ip cam.. you are seeing the image in your monitor with H.264 compression in effect so instead of resolving more details of the person face, you see jagged compression artifacts in his face... isn't it? This is why image quality is SDI then IP then CVI... ok.. why does CVI image more faded.. what is the figure of the percentage of the loss when the signal pass thru coaxial?

just putting it at the door & parking.. I want to see the person action real time in coincidence with his voice talking at the intercom or hearing them talk and see the walks in the screen... besides.. I already own 4 ip cams.. I want to try new technology either HD-SDI or HD-CVI but can't find other HD-SDI brand with the multiple functions of dahua cms and mobile viewers... Has any tried Avtech HD-SDI.. is the image quality much better than the ip cams?

In addition to the above comments.. note of this... I noticed the dahua ip cam with sony exmor sensor has better contrast than the dahua ip cam with aptina sensor (same models but with different sensors). therefore couldn't the cvi on the right picture be using the aptina sensor and sony exmor on the left? or are both the same sensors (what are they)?

So the resolution is still good enough to identify car plates.. only contrast is a bit loss from the losses in the analog propagation in the coaxial? Whatever.. cvi is good enough for zero latency live view with little loss of contrast as the cons. And the camera can still resolve detail at the resolving limits of the lens. So what else why you don't or anyone avoid the cvi?

I already have ip cams and want to try an HDSDI because I want latency at live view to be near zero. I won't get dahua HDCVI because it is just a low HD bitrate version as explained in this thread. So what is the best HDSDI brand now with the best live view camera image? If not HDSDI.. what is another option for zero latency live view aside from D1/960H analog. There seems to be no other choice.. are there? I can't help with HDSDI. I'm willing to submit that someone out there is doing it right, but out of all the models and manufacturers we went through, we never found one that worked reliably. I would say that if you're determined to pursue HD analog, the only option I can recommend is HDCVI. I haven't finished testing AHD or HDTVI yet. Just how bad is the dahua hdcvi compared to the dahua ip? I heard the dahua hdcvi is worse than their own ip models.. how bad? pls. someone supply image comparison at 1080p. the 1080p hdcvi is newer. so how does they manage to squeeze that much data in the analog.. they can only do it with 720p originally. would the cable demand become more sensitive?

I have a spare nvr.. how can I use it to record tv show.. is there some kind of HDMI to ip in converter so the nvr can detect it (and record it)?

I already have ip cams and want to try an HDSDI because I want latency at live view to be near zero. I won't get dahua HDCVI because it is just a low HD bitrate version as explained in this thread. So what is the best HDSDI brand now with the best live view camera image? If not HDSDI.. what is another option for zero latency live view aside from D1/960H analog. There seems to be no other choice.. are there?

I installed this dome camera outdoor and the 3 screws holding the body is only very thin.. one can just pull the whole dome cam off with one hand. How's your experience about installing dome camera outdoor? It appears bullet cam has metal base/body while dome camera has thin plastic case.. Have you come across metal dome cam? But since it is not good to mix different brand nvr and ip cam due to unable to control motion detect or even stream setting. Is it possible to put some kind of armor into an existing plastic dome camera?

how many length of cable before this degradation over distance becomes significant.. how about 22 meters? what is the estimated percentage of degradation..?

Hi, Why is Dahua megapixel Hdcvi image quality lower than Dahua megapixel ip quality? The ip cam compresses it at the source.. the hdvci is raw data to the recorder so should be higher in quality in principle.. I have 4 dahua ip cams and wondering whether to replace this with hdvci thinking the image quality may be better but you said hdcvi has lower image quality.. what are the exact technical reasons.. i'm more into the technical details.. tnx

I got my 4th ip cam to avail of the poe... after payment.. I realized if I made a mistake. Ip cam main advantage seemed to be the single cat5 sharing data and power. But HDCVI (or HD-SDI) doesn't have any latency.. the monitor view is simultaneous with the camera. It is about 60% cheaper. Feeds are immediately available in the monitor. So why Ip cam? What is really the advantage of Ip cam? I am thinking if I should have gotten the HDCVI instead and made mistake in getting the more expensive ip cam. My Nvr can support up to 4 1080p.. but the HDCVI recorder can support up to 1080p too. And my Nvr has separate 10.1.1.1 poe that you can't access anywhere in the network. Initially I should have gotten HD-SDI but I heard you need top quality coaxial (or it chooses certain ones).. but with HDCVI.. can you now use any cable even at 1080p? So I can know whether to replace my entire ip cams or get HDCVI in my next location suivellance project. Thank you.

An IP cam has web service page inside where you can adjust settings like BLC, chroma... whereas in cvi or sdi.. you can't go inside because it is not ip based... now what is the more common settings that you need to adjust that you can't do in the analog based cams? My ip cams are inaccessible because my nvr has their own 10.1.1.1 poe switch whereas the nvr itself is based on 192.168.1.*.. so if I get an external switch with poe.. they don't have their own ip address but based on the router? What 4 channel poe switch have you encountered that is the tinest possible?

I used mobile cellphone 3G as the internet service provider and transfer speed is only 600kbps.. so there is really a 3 minute latency. But if the source is cvi or sdi, are you saying it will send every 20th second frame such that you receive real time picture frame every 20th second versus ip where the picture frame 2 minutes before are buffered and send 2 minutes later.. or something like this?

they explained the latency is bec of the ip packet nature of it.. how about in the Hdcvi.. when the recorder goes to the internet and the internet is very slow (like mobile sim card used). Would there be delay in the signals from the nvr to you home.. making it say 3 minutes late... or would this not occur in HDCvi or HD-Sdi because it is allegedly continuously that even when there is not enough bandwidth for remove viewing, the streams still reach you real time even if broken so what happened elsewhere is real time here even passing thru 4g router with slow internet..? or would the pure streams from the HDcvi or Hd-sdi still be packetized in the router? or Not at all??

I have an NVR which doesn't have POE and neither the ip cam and their distance is 10 meters. Looking at pin assignment of an Ethernet cable. http://www.zytrax.com/tech/layer_1/cables/tech_lan.htm One can noticed pin 4,5,7 and 8 are not used in a 10base setup (which is how the POE is possible.. does this mean all ip cam are 10base.. which one is 100base?). I know how to connect jack to lan cable since I have a crimper and have done it several dozen times. Can I just connect the used 1,2,3,6 and make use of any of the unused 4,5,7 and 8 pin as the 12 volts line by connecting the adaptor to one end and female jack to another end and plugging it into the 12 volt power input of the ip cam?

Here's the spec of the data cable Cat5e I'm using... http://pdf.datasheetarchive.com/indexerfiles/Datasheet-027/DSA00474140.pdf note it has Awg 24 which has maximum ampere of only 0.577 ampere http://www.cablesandconnectors.com/wiregauge.html In my original adapter with only pin 4 as + and 7 as - 12 volts and assuming the camera mentioned in the message prior to this draws in 1 ampere maximum at 12 volts (12 watts).. it may not survive... but using pin 4 and 5 as + 12 volts can split the say 1A into 0.5A.. but I the camera draws in more than 1 ampere (the company refuse to write the power requirement), then the cable won't last for years. therefore based on the data.. I think I must get a new POE cam and sell the old one...

btw.. this is the camera.... http://en.jovision.com/Products/ProductView.aspx?id=131 It is about one foot long and has 42 LEDs... anyone familiar with such length camera? the wattage is not written... and there is no included power supply... the local store just supplied 1A 12 volts adapter. If you have something similar to this.. a dahua, Hikvision, Axis or others.. pls. mention what is the wattage indicated. After 30 minutes, the camera is hot and the adapter.. so I figure the wires must get hot too.

Remember pin 4, 5 and 7, 8 not used.. I initially just used pin 4 and 7 as + and - 12V.. but read in POE.. 4,5 are used as positive and 7,8 as negative.. so I can connect the positive (+) to both 4,5 and negative (-) to both 7,8? Ordering at amazon would take 2 weeks and I already made the hybrid wires. In those passive ejectors.. do they use both 4,5 as positive? I guess the power would distribute better in 2 wires than 1. Anyway. Are single wires in the Cat5E really Awg22 and maximum ampere 3A?

the wires in the cat5 is said to use awg 22 which can reach up to 3 amperes. my camera is big with 42 pcs of LED and it's power supply is 1A, 12V. Assuming it's 12 Watts (12V x 1A)... the manufacturer doesn't want to put the wattage rating in the spec (maybe may scare the customers away). What do you think will happen to a 1 ampere current passing thru the awg 22 wires 24 hours? and what is the wattage per LED of the 42 pcs? my lan cables are inserted into very tight small pvc inside cement and I can no longer replace just one without pulling all the wires and much work and hundreds of dollars of cost. If the wire keeps heating, would it just melt.. some years ago.. I have some electrical wires where the wires themselves get black. What other problems would happen if the cat5 wires keep heating? would this really occur at 1A 12 volts 24 hours or should I buy a POE cam that is 802.3af (and sell off my non-POE cam)?

how much wattage can a typical cat5e cable take? Note the wire is so tiny.. assuming the camera has 12 watts (12 volts x 1 ampere), won't be 12 watts heat the wire? or cause it to deteriorate faster? Note that in POE, 48 volts is used because "The IEEE has standardized on the use of 48 VDC as the Injected PoE voltage. The use of this higher voltage reduces the current flowing through the CAT5 cable and therefore increases the load and increases the CAT5 cable length limitations. Where the maximum cable length has not been a major consideration some vendors have chosen 24 VDC and even 12 VDC as their "injected" voltage." but Cat5 cables are not all the same.. could all take the highest wattage possible in an IP cam with say 24 IR LEDS? I guess POE IP cam have lower wattage (between 5 and 6 watt) than non-Poe cam (12 watts or so). Do you agree?

I'd like to understand the source of my 10 sec latency. I connected my 802.11g Ipad to a 802.11n wifi router connected to a 4 channel nvr and get about 10 sec network latency (but only few millisecond monitor latency) so I'd like to understand where is the bottleneck. As I understand it. An ip cam encodes raw video into H.264, then the nvr decodes back into raw for vga monitoring.. then it encodes it again into H.264 for recording? Then when sending to internet.. it is the same recorded stream being sent out where the cms decodes back the signal to raw.. so I wonder if my 10 sec network latency is due to the recording encoding not powerful enough or the 802.11n not fast enough for it or the result of the built-in separate network of the dahua 10.1.1.1 POE. What is your guess? What would happen when you try to record 4 channel of 1080p in an Nvr that can only take 2 channel of it. Would the recording hang or would it become very slow. In different brands. Do they show warning that maximum resolution exceeded or no warning and just maybe resize it to lower resolution automatically?