TVL Spec for digital cameras?

chippy

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I'm looking for a cheapo IP camera with IR cut, without leds, POE onvif to connect to my nvr. Found several possible candidates on aliexpress, but they spec out the "TVL". I thought TVL was only used for analog cameras? I don't remember seeing that on my Hikvision 4mp cameras.

For example:

http://www.aliexpress.com/item/Mini-HD-IP-Camera-1-0-1-3-Megapixel-720P-960P-POE-Connector-Security-Camera-IP/32255518540.html?spm=2114.01010208.3.76.FkimXW&ws_ab_test=searchweb201556_10,searchweb201602_5_10017_405_404_301_507_10040,searchweb201603_7&btsid=dacb4d65-dbdc-4b79-b91d-73e770abc750
 

Del Boy

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I'm looking for a cheapo IP camera with IR cut, without leds, POE onvif to connect to my nvr. Found several possible candidates on aliexpress, but they spec out the "TVL". I thought TVL was only used for analog cameras? I don't remember seeing that on my Hikvision 4mp cameras.

For example:

http://www.aliexpress.com/item/Mini-HD-IP-Camera-1-0-1-3-Megapixel-720P-960P-POE-Connector-Security-Camera-IP/32255518540.html?spm=2114.01010208.3.76.FkimXW&ws_ab_test=searchweb201556_10,searchweb201602_5_10017_405_404_301_507_10040,searchweb201603_7&btsid=dacb4d65-dbdc-4b79-b91d-73e770abc750
If you buy from Aliexpress and don't read the entire advert then you are going to get burnt.

Copy and paste below:

[FONT=&quot]2.720P and 960P Optional ! "700TVL" in the option refers to 720P ,"750TVL " refers to 960P !!!![/FONT]
 

chippy

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I saw that. It's exactly what I'm asking. I always thought nnnP was digital. And "TVL" was analog. Where am I in error?
 

Del Boy

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I saw that. It's exactly what I'm asking. I always thought nnnP was digital. And "TVL" was analog. Where am I in error?
It's quite self-explanatory: It means if you select 700TVL version you will get 720P camera, if you order 750TVL then you will get 960P camera. Has nothing to do with analog or digital, just a way of them listing an option.

Don't take this the wrong way but you really shouldn't be ordering no-brand cameras from aliexpress to save a few dollars. You're going to get yourself into trouble and waste time trying to fix it. I'm trying to save you some time and money with that advice.
 

chippy

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With all due respect, I don't find it self-explanatory at all. I find it contradictory. At best, it's ambiguous.

TVL is tv lines. "p" stands for progressive scan. My thinking is "TVL" must be analog (tv). Maybe it can be digital too? Nothing I've read indicates it can be digital. Not finding evidence is not evidence that a thing doesn't exist. Conversely, progressive scanning, in my limited experience, is associated with digital. Perhaps it can be analog as well? Idk. That's why I asked the question. I was hoping it was a simple question and that someone here might be able to clarify it easily for me. Maybe it's some standard convention to mix "p" and "tvl" specific to security cameras. More than likely, it's a seller trying to obfuscate the fact that their cameras are crap.

So, in my mind saying [FONT=&amp],"750TVL " refers to 960P [/FONT][FONT=&amp][/FONT]is equivalent to "Red" refers to blue.

If you'll extend me the equal courtesy of "not taking this the wrong way," I'd like to say that your response came off as condescending. I'm not some rube that doesn't read ads. Nor have I required someone to pat me on the head and trust that they know best how I should spend my time or money for 40 years or so. I appreciate the concern, but rather than trying to steer people where you think they should go, how about offering them your opinion as to why you think it's a bad idea. Then let them decide for themselves. Wasting money isn't my primary concern for buying a camera. Really. Saving a hundred bucks is not the issue here.
 

fenderman

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With all due respect, I don't find it self-explanatory at all. I find it contradictory. At best, it's ambiguous.

TVL is tv lines. "p" stands for progressive scan. My thinking is "TVL" must be analog (tv). Maybe it can be digital too? Nothing I've read indicates it can be digital. Not finding evidence is not evidence that a thing doesn't exist. Conversely, progressive scanning, in my limited experience, is associated with digital. Perhaps it can be analog as well? Idk. That's why I asked the question. I was hoping it was a simple question and that someone here might be able to clarify it easily for me. Maybe it's some standard convention to mix "p" and "tvl" specific to security cameras. More than likely, it's a seller trying to obfuscate the fact that their cameras are crap.

So, in my mind saying [FONT=&amp],"750TVL " refers to 960P [/FONT]is equivalent to "Red" refers to blue.

If you'll extend me the equal courtesy of "not taking this the wrong way," I'd like to say that your response came off as condescending. I'm not some rube that doesn't read ads. Nor have I required someone to pat me on the head and trust that they know best how I should spend my time or money for 40 years or so. I appreciate the concern, but rather than trying to steer people where you think they should go, how about offering them your opinion as to why you think it's a bad idea. Then let them decide for themselves. Wasting money isn't my primary concern for buying a camera. Really. Saving a hundred bucks is not the issue here.
Listen to del boy. Aliexpress simply does not have an option to list at 720p or 1080, they would have to set a new page. The tvl number is completely meaningless, it simply allows you to choose between resolutions. Red can refer to blue if the website does not have a mechanism to indicate blue. Del boy is trying to help you avoid waste. If you did not know this basic aspect of aliexpress, that means you never purchased a camera via ali before.
 

Del Boy

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why you think it's a bad idea
I wasn't being condescending. If you couldn't appreciate the advice that's not my issue.

It's a bad idea because if you haven't purchased a camera off Ali before and don't understand the advert after it's been explained 3 times now (it can't be analog as well) then you probably will have issues with this camera and come back here to say it doesn't work.

More than likely, it's a seller trying to obfuscate the fact that their cameras are crap.
No, it's not. Let me explain one last time as your last reply showed you don't understand and haven't read the ad. These are IP cameras (not analog). There is a choice between 720p or 960p camera, also known as 1MP or 1.3MP camera. If you select 700TVL they will send you a 720p camera, if you select 750TVL they will send you a 960p camera. Nothing to do with seller trying to obfuscate as the cameras are clearly rubbish. Nothing to do with Analog as the pigtail clearly shows that as does the specifications.

My original advice stands, if you thought this camera could be analog too then you shouldn't be buying a no-brand from Aliexpress.
 

chippy

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Thank you @fenderman. I realize what del boy is saying. But your explanation isn't the way he put it. He reponded to the OP, "read the whole advert". Next post, he said "it's self-explanatory". Self-explanatory means it is syntactically correct... that red is red. Blue is blue. Not red is blue if you know how aliexpress is set up. The latter is NOT self-explanatory.

Still, the question the OP asks, paraphrased, "Is TVL only used for analog?" I would have likely come to the conclusion that aliexpress has no provision for dpi and the thread would have ended with "Yes, it's only for TVL, but aliexpress has no provision for dpi or MP so "TVL" is a substitue, poor that it may be." Followed by "Ok, thank you." It's far more expedient in my opinion.

Plus, knowing that aliexpress does it this way, still does not exclude the possibility that "TVL" could be correctly used to spec digital cameras as well. I'm left, less than 100% certain that TVL is exclusively used for digital (because the OP remains unanswered), if one wishes to be accurate. Sometimes, a question is just a question. Personally, I think answering questions not asked in place of the answer sought should be left to politicians. Maybe I'm alone in that.

No ill-will intended. Just trying to illustrate the other side of this.
 
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chippy

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I wasn't being condescending. If you couldn't appreciate the advice that's not my issue.
I don't know what to say, but I'll try :) Did you not read where I said, "I appreciate the concern?" I'm sorry if my "appreciation" of your advice wasn't sufficient. It's wonderful when a boy scout helps the little old lady across the street.... if she asks.

It's a bad idea because if you haven't purchased a camera off Ali before and don't understand the advert after it's been explained 3 times now (it can't be analog as well) then you probably will have issues with this camera and come back here to say it doesn't work.
Really? It can't be analog AND digital? Why do you think I might be asking the question. Where I come from, we call that a "contradiction." While I admittedly have never purchased anything from aliexpress, I have made thousands and thousands of dollars worth of purchases on places like Amazon and Ebay. Do you think this is the first time I've ever read a contradiction in an ad? No. The thing is, I really didn't know for sure, because I am new to this stuff as you know from previous threads, if TVL was exclusively analog spec. I was pretty sure, but when I am in possession of two seemingly contradictory bits of knowledge, I assume one is probably wrong. I don't just pick one and go in. I like to weed out any garbage in my brain. I didn't realize asking a simple question was going to be such an affront to you. I'm truly sorry if I've upset you.

No, it's not. Let me explain one last time as your last reply showed you don't understand and haven't read the ad.

This is an example of what I find condescending. While you might have hinted around at the question I originally asked, you didn't answer it directly. At best, you implied an answer.

These are IP cameras (not analog).
Yes, I thought they were. I had absolutely NO reason to think otherwise EXCEPT for the "TVL".
There is a choice between 720p or 960p camera, also known as 1MP or 1.3MP camera. If you select 700TVL they will send you a 720p camera, if you select 750TVL they will send you a 960p camera. Nothing to do with seller trying to obfuscate as the cameras are clearly rubbish. Nothing to do with Analog as the pigtail clearly shows that as does the specifications.

My original advice stands, if you thought this camera could be analog too then you shouldn't be buying a no-brand from Aliexpress.
See, this is what I'm trying to say... you didn't answer the question I asked. Instead, you danced around an answer. Then you mainly just gave advice not asked for then act offended that I didn't appreciate it. FOR THE THIRD TIME, I didn't think the camera was analog. I was confused whether or not it was appropriate to use TVL to spec a digital camera.

If something I've done or said offends you (besides simply being ignorant about cameras and aliexpress, which I freely admit), please point it out to me. Clearly, I've gotten under your skin. I feel like I'm the only one here who has any cause to gripe (albeit an insignificant and easily overlooked cause). I recognize that perhaps I've done or said something I'm not aware of. I would like to correct the transgression and apologize. Friends?
 

Del Boy

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I tried to help and you went off the handle defending yourself when I was trying to help you not make a mistake. It's as easy as that. Can you not see that if you can't understand the advert that buying one of these cameras is a bad idea?

It's your money and your choice at the end of the day. But if you get that camera and this is confusing you, imagine the possible Chinglish support you get off the seller?

I wasn't dancing around the issue or being condescending "It means if you select 700TVL version you will get 720P camera, if you order 750TVL then you will get 960P camera." You haven't gotten under my skin but if you want to completely pick apart and analyse my replies then I'll be reluctant to help in the future.

I'll leave it at that and put it down to a misunderstanding not helped by my curt style at times and let bygones be bygones. Edit: Also a few idiots have riled me up recommending rubbish recently (not you), so don't take anything on here personally. I don't make personal attacks on anyone so apologies if it sounded that way.

Here is maybe some better advice: http://www.aliexpress.com/item/Dahua-1-3Mp-support-POE-IPC-HFW2100P-HD-Network-Water-proof-IR-Mini-Bullet-IP-Camera/1940945488.html?ws_ab_test=searchweb201556_10,searchweb201602_5_10017_405_404_507_10040,searchweb201603_11&btsid=f7929065-d0a4-4f20-9553-2493a256c1a5 Dahua HFW2100P, ONVIF (yes), PoE (yes), No IR (ok it has but take it to bits and disconnect it). Yes it's twice the price but you are getting over twice the camera.
 
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chippy

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I tried to help and you went off the handle defending yourself when I was trying to help you not make a mistake. It's as easy as that. Can you not see that if you can't understand the advert that buying one of these cameras is a bad idea?
For the record... "I didn't go off the handle" as you put it. I wasn't "defending myself." I was trying to clarify what I was asking and pointing out that your response didn't answer the question. You seem to keep wanting to make this about the advice you gave. I didn't ask for advice at any point in this thread (though I have in others). I'm not making any claims about the quality of your advice. I was courteous and told you, "I appreciate your concern, but it doesn't answer the question I asked." My feelings on advice are simple. If it wasn't asked for, it should be given with the understanding that the person it's given to may or may not dispose of it as he or she will.

You also demonstrated a faulty conclusion that indicates you're assuming a great deal. Namely: Inability to understand an advert = buying item advertised is a bad idea. First of all, who the hell are you to tell me what is a bad idea for me? If you want to debate absolute objectivism, perhaps we should take this discussion to a philosophy forum. What might be "bad" to you might be "good" to me. If I wanted what YOU might consider "good," I'd spend $150 and call it a day. I indicated "cheap" knowing what that means. It's $20, hardly worth losing sleep over after spending $1300 on a surveillance system.

Respectfully, if you're going to lecture me about "seeing" my error in purchasing a camera (pointing out I haven't indicated that I intended to buy THIS camera), I'd ask that YOU "see" that I simply asked about what TVL referred to because I was previously "100%" certain that it was a reference to analog. The ad was contradictory in my view. I was questioning a datum of my knowledge (tvl = analog). Of course, NOW I see that I was correct in the first place, apparently. If you fail to "see" THAT, I would hope that you could at least see that Shopping and/or Comparing != Buying. Partly, "understanding" requires that we don't assume what is in someone's mind. All we ever have to go on is what we're told (when not in person to witness other cues).
It's your money and your choice at the end of the day. But if you get that camera and this is confusing you, imagine the possible Chinglish support you get off the seller?
Thank you for recognizing that it's my money. It's a very enlightened stance. But, like I said... I was shopping. While that sometimes leads to buying, it is far from a foregone conclusion.

I wasn't dancing around the issue or being condescending "It means if you select 700TVL version you will get 720P camera, if you order 750TVL then you will get 960P camera." You haven't gotten under my skin but if you want to completely pick apart and analyse my replies then I'll be reluctant to help in the future.
I felt condescended to. Thank you for dismissing that feeling. I feel better. I merely told you so they you might take my advice, if you so choose, so as to not be perceived similarly by others. Feel free to disregard or "appreciate" that advice. It's just my opinion. I promise to not get my nose bent out of shape if you don't agree that it's good advice.

I'll leave it at that and put it down to a misunderstanding not helped by my curt style at times and let bygones be bygones. Edit: Also a few idiots have riled me up recommending rubbish recently (not you), so don't take anything on here personally. I don't make personal attacks on anyone so apologies if it sounded that way.
I have asked for advice on this forum. I think you are one that probably gave me some that I've taken... I don't recall. But, overall, I am satisfied with the system I bought from Nelly's. Most importantly here, I in no way felt you were attacking me. I sincerely hope you feel likewise! I would defend you against anyone here who said you had attacked me personally! No apology necessary.

Here is maybe some better advice: http://www.aliexpress.com/item/Dahua-1-3Mp-support-POE-IPC-HFW2100P-HD-Network-Water-proof-IR-Mini-Bullet-IP-Camera/1940945488.html?ws_ab_test=searchweb201556_10,searchweb201602_5_10017_405_404_507_10040,searchweb201603_11&btsid=f7929065-d0a4-4f20-9553-2493a256c1a5 Dahua HFW2100P, ONVIF (yes), PoE (yes), No IR (ok it has but take it to bits and disconnect it). Yes it's twice the price but you are getting over twice the camera.
Thanks for the link. I might actually buy one to try, based on your recommendation. However, that in no way would be a substitute for the question I asked in the OP. I hope I've made that clear now.

Aside from that, one thing I'm looking for in a cheap camera is hideability. I didn't mention that in the OP, because I wasn't looking for suggestions here. I'd actually asked for those suggestions in another thread and only had one person reply.

Anyway... no hard feelings on my part. I try to be very precise and deliberate in what I write (and what I read). Having the advantage of the written word gives us all a chance to reread (both posts we write and don't write) to improve understanding. If I've in some way failed to do that here, I apologize and am sincere in asking for anyone to point out my failures in effective writing.

Cheers
 

tangent

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Many Ali Express sellers also use TVL for different lens options. It does seem strange, I attribute it mostly to the language barrier. Occasionally you'll see a seller that actually knows how to give you the choices you'd expect instead of TVL, but it's rare.

TVL is TVL except when it's not...
 

Kawboy12R

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My take on it is that ALiExpress wrote the code in the ad pages for describing analog cameras ages ago and hasn't done any updating to improve the choices for IP cameras or cams with different lenses. Today's sellers are just making due with what they have available. It should be a simple change to improve it but that'd cause Ali some effort and cost them a few dollars. So, nope. Hell, they've got kids over there in elementary school that could rewrite that code properly. Make it a homework assignment and they wouldn't have to spend a cent in code, just in rolling it out.

I see it almost like all the cameras with autoexposure set to autoadjust to 1/25th or slower and stay there if it isn't bright sun out. Anybody with access to the code could change the timing a bit, or maybe add a checkbox or two for "Sport Mode" in the day and night section and vastly improve captures for moving subjects. Trivial, really. But why isn't it done? Beats me. Seems like a simple and common sense thing to do to upgrade things. Spending a few dollars and changing the mindset seems to be like winning a staring contest with a brick wall.
 

chippy

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I see it almost like all the cameras with autoexposure set to autoadjust to 1/25th or slower and stay there if it isn't bright sun out. Anybody with access to the code could change the timing a bit, or maybe add a checkbox or two for "Sport Mode" in the day and night section and vastly improve captures for moving subjects. Trivial, really. But why isn't it done? Beats me. Seems like a simple and common sense thing to do to upgrade things. Spending a few dollars and changing the mindset seems to be like winning a staring contest with a brick wall.
I know what you mean. I see this all the time with Chinese products. While many are quite acceptable, the vast number of products that get most everything just right, only to fail on one (or two) small, simple and inexpensive corrections to make a really good product. The HooToo cameras I mentioned in another thread for example... I was impressed with most of it. It's attractive, images are really good (for 720p), and could easily fetch twice as much retail if they'd just fix the web interface. A few lines of code and testing and your profit margin triples. Like you said, there's an infinite supply of Chinese elementary school kids that could do it. I would even give HooToo an 85% on the manual's English grammar... the bane of most Chinese products. Oh soooo close! Maybe it's the Chinese version of "planned obsolescence?" Sell products that are close, but ineffectual so the consumer is forced to buy a better made (Chinese, of course) product?
 
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