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Resolution Lies

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Hello, I wish Mythbusters would do an episode on CCTV camera resolution vs marketing hype that seems to be flat out lies.

 

From the research I've done, the only Sony color CCD that produces a true 540 tvl is the HQ1 chip. Yet, I see hundreds of companies, from manufacturers to retailers that advertise Sony super HAD at 500, 520, 540, 580, (even one of your partners of this forum advertises an ARM analog Sony color super HAD at 600+ tvl of resolution. How is that true?).

 

I can't believe that so many companies would flat out lie, so I'm asking what are some of the tricks that companies use to inflate their specs? I figure one way would be to list the B/W resolution on a Day/Night camera. Do some cameras come with a digital conversion to up the resolution?

 

I sell cameras and I'm sick of losing sales to inflated specs, but I will not join the bandwagon. Does anyone have a link that lists all of Sony's CCD chips? I found a Sony global website with complete engineering specs, but nowhere can I find mention of the term "HQ1".

 

Maybe I'm completely wrong, but either way I would like some help on the issue please.

 

-Matt

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I`ll sell you a 800 line super-giga mega HAD sony for $99

oh its got a 900x digital zoom.....

 

the lies will stop once more megapixel cams get out there most people understand this...

 

z

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Hello, I wish Mythbusters would do an episode on CCTV camera resolution vs marketing hype that seems to be flat out lies.

 

From the research I've done, the only Sony color CCD that produces a true 540 tvl is the HQ1 chip. Yet, I see hundreds of companies, from manufacturers to retailers that advertise Sony super HAD at 500, 520, 540, 580, (even one of your partners of this forum advertises an ARM analog Sony color super HAD at 600+ tvl of resolution. How is that true?).

 

I can't believe that so many companies would flat out lie, so I'm asking what are some of the tricks that companies use to inflate their specs? I figure one way would be to list the B/W resolution on a Day/Night camera. Do some cameras come with a digital conversion to up the resolution?

 

I sell cameras and I'm sick of losing sales to inflated specs, but I will not join the bandwagon. Does anyone have a link that lists all of Sony's CCD chips? I found a Sony global website with complete engineering specs, but nowhere can I find mention of the term "HQ1".

 

Maybe I'm completely wrong, but either way I would like some help on the issue please.

-Matt

------------------------------------------------------------------

If u have retail store u can put your best camera and few other against

standard resolution chart which u can pick up in US for about $120-130

and let customer decide

after all it is their choice

that what i do

if u need more info about chart pm to me

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Customers need to pay more attention to the Effective Image Pixels instead of just TVL.

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If most of the customers would read the responses in this forum they would have a well rounded education on what to look for and make all our jobs easier. I have learned a lot just from reading what has been written in this forum. THANKS RORY!!

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I will agree that this forum is the best education, besides Damjanovski's books.

 

So companies are just lying then?

 

Yup! I have saved a lot of $$$ because of the info here!

 

I was concerned about replacing a 420 line b/w camera with a 380 line Eclipse ECL - 596

 

 

Guess what? The 596 beat the pants off of the old 420 line b/w! (yes there is a bit more noise at night, but the image is much clearer)

 

The one thing that I would love to see is image examples with cameras offered. Now I know that under certain conditions a cheap camera could look good, but if they at least tried to do an apples to apples image comparison, we might be able to make an educated decision.

 

If you go by specs alone, you could buy a lot of junk.

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I think you are looking in the wrong area. It isn't the CCD but the DSP that is the key to 520TVL.

 

Ignoring progressive scan and other such imagers, Interline (ILT) CCD's resolutions haven't changed in ages. You get two resolutions medium (or standard) and high and it doesn't change if the CCD is 1/4", 1/3" or 1/2".

 

The same CCD that was 480TVL three years ago can now be 520TVL the increase comes from the DSP not the CCD.

 

So the HQ1 you have seen refers to the DSP not the CCD. When I was a lad there was the 2163 aka SS1, open up any sony based camera that is a few years old and chances are it will say 2163BR on one of the chips. This was the first DSP Sony released and it is probably still in use today. Then came the SS11, I think this was a lower cost one, maybe only MR, can't remember. SS-HQ1 will be the 520 one.

 

As well as changing the DSP the filter in front of the CCD will be different.

 

A colour CCD has the same number of pixels as a black and white CCD. This begs the question why are the resolutions different. The resolution has to be stepped down on a colour or you will get colour fringing , the posh name is Moires, the simple name is barbers pole effect. The filter fitted in front of a colour CCD doesn't just cut out IR light. It also cuts out high frequencies. This bit is called Optical Low Pass Filter (OLPF). So the filter is an IR cut and OLP filter and this actually limits the resolution of a camera as well.

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All those sites selling Sony Bullet Cameras too .. LOL.

 

"I just bought a Sony Bullet Camera" .. say what??

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After doing more research, it seems the highest true resolution possible for an NTSC color analog camera is about 460 tvl. This includes the highest composite resolution minus the reduction of resolution because it is color. So these companies are claiming that the DSP increases the resolution by 40-140 tvl. What is the difference between active tvl and DSP tvl? Even though an analog system can only display 480 tvl, when the signal is digitized in order to be recorded on the hard disk, even more resolution is lost. Does the DSP compensate for this resolution loss due to conversion?

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Its 480TVL then they digitally enhance it to 520-540TVL

 

BW goes up to 600TVL though.

 

Doesnt really matter though as it all depends on the image pixels, some OEM bullets say 520TVL then their image pixels are 511x which match the 380TVL cameras .. should be 800x +- for high res.

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Also most cameras (all colour cameras?) lose their stated resolution(if it was real in the first place) as part of the AGC process in low light conditions. AGC means amplifying the signal creating noise, but there's also the reduction of the effective pixel count due to the creation of virtual larger pixels to increase the effective surface area of each pixel and therefore increase it's light gathering ability.

 

A camera that can produce 720x480 images in good light may only be delivering 360x240 or 180x120 resolutions at lower light levels due to this virtual enlarged pixel process. DSP via interpolation probably increases the effective resolution but on my Panasonics low light AGC conditions deliver terrible resolution.

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