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Do the cables make a difference in video quality?

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In analog systems, do the cables make a big difference in video quality? I've been using the "plug n play" cables that came with my bundled system(s)... which is pretty thin, I'm sure its cheap. Would buying baluns and running cat 5 give better video quality? or using thicker higher quality cables to each camera???

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Does the picture not look good now?

 

With analog video, better cables generally *will* show an improvement in the video, but you also have to be careful with the cheapie all-in-one/DIY camera kits. Many times the cameras themselves are relatively low quality, and the issue is not the cable, it's the camera.

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The camera's look "OK" now - honestly I dont think the video will get any better with better cables but I wanted to ask ... I know cables sometimes makes a difference in A/V stuff, but usually the jump is from "cheap thin crap" to anything decent cable or better...but from decent cable to ultra high end usually doesn't yield much of a difference.... unless you've got the eyes of an eagle, and at that point you're not using analog cameras anymore anyway- you're on IP cameras.

 

The reason I ask, the first DIY system(s) I bought had really small cheap wires with 1/4 sony ccd cameras... the last system I bought (Q-see Qt528) came with bigger 1/3 CCD sony DSP cameras, and VERY impressive heavy duty cables. I have not tried the cables, but there appears to be a HUGE difference in the cables... if you can imagine the cheapie cable being about the size of a #2 pencil (maybe thinner) and carries both video and power. The other cable (the more heavy duty cable) is 2 separate cables fuzed together in more of a flat ribbon cable, and the video portion is easily twice the thickness of the cheaper cable... But I sure don't want to go through the hassle of re-running these wires for no reason

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Cut one of those "high quality" thick cables in half sometime. 95% of the time they have the exact same amount of metal as cheap cables, and about 300% more insulation to bulk up the cable and make it appear to be more robust.

 

Years ago when I was starting an A/V store, I was visited by a local rep of one of the premier higher-end (marketed above Monster) cable companies. Came in giving a big pitch about the need for ~10% of the home theater budget to go to cables that can deliver superior sound and image quality and so on. So I played along with him, nodded my head, etc. I asked him if his cables really made that much of a noticeable difference, and of course he told me they did.

 

So, I took him to the lower floor of my store and showed him where we were building some reference home theater demo rooms. I told him I'd take my $25,000 theater room and duplicate it exactly. One room would use all the default/free cables, and the other room would use all his high-end cables. That way, customers could clearly see and hear the difference between the two setups in a true side-by-side comparison. Then he starts backpedalling, telling me that's not a good idea. It would just confuse people, they are are coming in for my "professional advice and design" and yadda yadda. Never saw him again after that.

 

Good cables are necessary for a proper system, but the bar between "utter crap" and "more than sufficient" is actually pretty low in most cases. If the output isn't what you're expecting, it's rarely the cable. Terminations however, especially hack easy DIY connectors, CAN be problematic though.

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Good cables are necessary for a proper system, but the bar between "utter crap" and "more than sufficient" is actually pretty low in most cases. If the output isn't what you're expecting, it's rarely the cable. Terminations however, especially hack easy DIY connectors, CAN be problematic though.

 

 

That's exactly why I said in the original post the jump from cheap crap to something decent is ok, but after that its pretty much a level playing field. At least that's been my experience in A/V stuff anyways..... Like these guys talking about $100 HDMI cables are necessary for 3D TV, 1080p or HDMI 1.4a compliance, etc... My $3.00 HDMI which is years and years old, works just fine for 1080p, 3D TV, bluray, etc....

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100' of cheap stock cable, the thin premade stuff-

That cable wouldn't last a few feet on most jobs

RG59 siamese even got ripped on a job I am pulling now.

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I'm not suggesting it's right for everyone and if I were a pro installer, I would never use it. But, on my diy home job it's working fine. As I said though, your mileage may vary- YMMV.

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In analog systems, do the cables make a big difference in video quality? I've been using the "plug n play" cables that came with my bundled system(s)... which is pretty thin, I'm sure its cheap. Would buying baluns and running cat 5 give better video quality? or using thicker higher quality cables to each camera???

I did a quick experiment a while back, good coax vs. cat5 and cheap baluns. Coax was slightly better. Shielding of coax varies widely, usually stated as a %. For the trouble of coax I can see why people would do baluns.

 

I also have some cheap coax from a box system which is not bad at all. Where you start to notice more probably is real environments - i.e. routed by noisy lines. I would not waste time upgrading cables if going to IP (even non-MP) is an option for you - MUCH better picture quality.

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There are several factors.

Generally, the more distance between your camera and your DVR - the more influence has cable type.

 

The more resolution your camera has - the more influence has loss of hight frequencies of your cable. Color cameras require better high frequency transmission.

The less voltage camera output has, the less sensitivity your DVR has - the more influence has cable resistance. The thinner your cable is - the less its resistance and the more its loss of high frequencies.

The more radio interference on your place - the more influence has shielding of your cable.

 

Thus is some conditions there can be no visible difference between different cables, but in other conditions there can be big difference.

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Don't forget the connections they can be as important as the cable. As far as super high end cables go there is more market that tech. We bid jobs all the time calling for specfic brand spec cable but it is more to keep out the very cheap copper clad alum. Guys putting out specks don't want issues later on.

 

SOmeone told me about a demo someone was doing with high end cables for audio vs cheap stuff no one could tell the difference (very short runs of course between the high end copper and two coat hangers.

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There are several factors.

Generally, the more distance between your camera and your DVR - the more influence has cable type.

 

The more resolution your camera has - the more influence has loss of hight frequencies of your cable. Color cameras require better high frequency transmission.

The less voltage camera output has, the less sensitivity your DVR has - the more influence has cable resistance. The thinner your cable is - the less its resistance and the more its loss of high frequencies.

The more radio interference on your place - the more influence has shielding of your cable.

 

Thus is some conditions there can be no visible difference between different cables, but in other conditions there can be big difference.

 

Would you like to rethink that ? The loss of high frequencies is usually the result of capacitive reactance of the dielectric not the DC resistance of the cable

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The thinner your cable is - the less its resistance and the more its loss of high frequencies.

 

Of course I should write "The thinner your cable is - the more its resistance " Thank you for this correction. Thinner cables have worse quality and less price. They have more losses in hight frequences, than thick cables. Actually thin cables have more losses in direct current too, but in hight frequences their losses are much more. Thin cables have worse amplitude-frequency characteristic.

 

 

The loss of high frequencies is usually the result of capacitive reactance of the dielectric not the DC resistance of the cable

 

Not exact. Loss in high frequance is caused by resistance too.

 

"Shunt capacitance per unit length, in farads per metre." and "Series inductance per unit length, in henrys per metre" don't lead to losses. These parameters determine "Characteristic impedance in ohms (Ω).".

Losses are caused by "Series resistance per unit length, in ohms per metre" and "Shunt conductance per unit length, in siemens per metre.".

 

"Series resistance per unit length, in ohms per metre- The resistance per unit length is just the resistance of inner conductor and the shield at low frequencies. At higher frequencies, skin effect increases the effective resistance by confining the conduction to a thin layer of each conductor."

"Shunt conductance per unit length, in siemens per metre. The shunt conductance is usually very small because insulators with good dielectric properties are used (a very low loss tangent). At high frequencies, a dielectric can have a significant resistive loss."

 

See details: http://en.wikipedia.org/wiki/Coaxial_cable#Fundamental_electrical_parameters

 

Thus the Series resistance and Shunt conductance are raised on hight frequences.

Because of thinner cables have more "Series resistance per unit length" and "Shunt conductance per unit length" than thick cables, they have more losses in high frequences.

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