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"true day/night", what is it?

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Ok, here is one that will probably seem a very dumb question to be asking. I have read many times about "day/night" cameras, "true day/night" cameras which I do not even know if it would be the same, so the question is as simple as "what is a day/night camera"? (or "true day/night", whatever).

 

I understand that it would be a camera with night vision (with infrarreds?) that has a mechanical IR filter, so it will filter out the IR during the day. This way, it will show good colors during the day, since it will not receive any IR, and then it will also have night vision. Is that about correct?

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Is that about correct?

 

Yes, and other features may include: improved low light performance, a sensor that is sensitive to IR, a lens that is optimized for both visible and IR, and possibly an auto back focus since IR typically has a difference focus point.

 

Best,

Christopher

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As long as it has a removable IR cut filter then its a True Day Night, also labeled as TDN and ICR. It doesnt always have Infrared built in such as with non IR Domes and Box cameras.

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Thanks on your inputs, but I am still not sure I have a clear "definition" on that "day/night" thing (TDN from now on as rory stated).

 

So a TDN camera is just a camera that has good vision at night? Because, is there any way to measure how good TDN a camera is? Ok, so there are cameras with no IR that are called TDN, what I think would be my question is, how would a TDN camera be defined? What specs must it meet, if there is actually some specs to be called TDN? Or is TDN just merchandising, which manufacturers apply to their cameras as they see fit?

 

As long as it has a removable IR cut filter then its a True Day Night, also labeled as TDN and ICR.

 

Like, it CAN have removable IR cut filter, or it MUST have one so it can be called TDN? All this questions are because we have never called any of the cameras we sell "day/night" with those words, because we wouldn't even be able to say "why" we would be calling it TDN...

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Thanks on your inputs, but I am still not sure I have a clear "definition" on that "day/night" thing (TDN from now on as rory stated).

 

So a TDN camera is just a camera that has good vision at night? Because, is there any way to measure how good TDN a camera is? Ok, so there are cameras with no IR that are called TDN, what I think would be my question is, how would a TDN camera be defined? What specs must it meet, if there is actually some specs to be called TDN? Or is TDN just merchandising, which manufacturers apply to their cameras as they see fit?

 

As long as it has a removable IR cut filter then its a True Day Night, also labeled as TDN and ICR.

 

Like, it CAN have removable IR cut filter, or it MUST have one so it can be called TDN? All this questions are because we have never called any of the cameras we sell "day/night" with those words, because we wouldn't even be able to say "why" we would be calling it TDN...

 

The camera must have a removable IR cut filter to be a TDN.

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The camera must have a removable IR cut filter to be a TDN.

 

So, any camera that has removable IR cut filter can be called TDN? That is, that TDN would be just another way of saying a camera has that? If so then I will have to find out how to find that out... today I looked closely at several box cameras to compare, trying to look for a "mechanical" IR filter. I did see some cameras that apparently had filters in front of the sensors, but I am not sure I saw any that had a removable one...

 

(Also read around about IR cut filter being called ICF, so ICF and TDN would be the same?)

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That is, that TDN would be just another way of saying a camera has that? If so then I will have to find out how to find that out... today I looked closely at several box cameras to compare, trying to look for a "mechanical" IR filter.

 

Are you trying to find a camera with an IR cut filter, or are you trying to find a camera that will perform well at your location? Just because a camera has an IR cut filter does not mean it will perform well during day and night.

 

Best,

Christopher

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Like, it CAN have removable IR cut filter, or it MUST have one so it can be called TDN? All this questions are because we have never called any of the cameras we sell "day/night" with those words, because we wouldn't even be able to say "why" we would be calling it TDN...

 

1-Digital Day Night Camera - no IR cut filter, switches between Color and BW mode without any moving parts, also known as a Color IR Camera if it has built in Infrared, a less expensive way to do it, trade off can be washed out colors.

 

2-True Day Night Camera - Has an removable IR cut filter, switches to Color mode and the IR Cut filter is placed over the chip to block out any Infrared (particularly useful in outdoor situations where there is alot of bush and trees), Switches to BW mode and the IR cut filter is removed. Moving parts, better color image during the day, however more chance of failure if it switches too much.

 

If its a Day Night camera it is either #1 or #2

#2 costs more due to the extra feature but its generally a better camera, a better overall image.

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The camera must have a removable IR cut filter to be a TDN.

 

Bingo .. thats the bottom line.

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You can measure the how good a camera is at seeing in low light fairly well by its minimum illumination.

 

For example, the VBM-24VF, which is a True Day/Night dome, can see down to 0.005 Lux in night mode (B/W). That's quite good! It can see that well because of it's IR cut filter and very sensitive DSP.

 

Then take a DFL-20S, which is just a normal indoor dome. It too switches between color (day) and B/W (night), although it doesn't have the IR cut filter. It's minimum illumination is 0.05 Lux. Not bad...

 

Also be aware that if specs for a camera say 0.0 Lux, that could be anything between 0.00 and 0.09. So don't just look at the zeros and be fooled.

 

Now minimum illumination isn't the only factor in how well a camera performs in low light. Other factors include the size of the sensor, be it 1/4, 1/3, or even 1/2 inch. Also, what the resolution is: A 480 line camera may do better than a 500 line camera in low light, because each little pixel on the sensor is bigger, and collects more light. There are other things like lenses and such that have smaller effects on low-light vision as well..

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You can measure the how good a camera is at seeing in low light fairly well by its minimum illumination.

 

For example, the VBM-24VF, which is a True Day/Night dome, can see down to 0.005 Lux in night mode (B/W). That's quite good! It can see that well because of it's IR cut filter and very sensitive DSP.

 

Then take a DFL-20S, which is just a normal indoor dome. It too switches between color (day) and B/W (night), although it doesn't have the IR cut filter. It's minimum illumination is 0.05 Lux. Not bad...

 

Just a correction, that 0.005 is really 0.05, they exaggerate allot on the lux levels these days, they fail to explain that is faceplate which means little. And while the DFL is a nice dome for the cost, it cant see anything in low light, that being at approx 0.5 lux.

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Are you trying to find a camera with an IR cut filter, or are you trying to find a camera that will perform well at your location? Just because a camera has an IR cut filter does not mean it will perform well during day and night.

 

No no, not at all... I am just trying to be able to understand in the future what exactly is or makes a camera be called "day night" or "true day night"

 

1-Digital Day Night Camera - no IR cut filter, switches between Color and BW mode without any moving parts, also known as a Color IR Camera if it has built in Infrared, a less expensive way to do it, trade off can be washed out colors.

 

2-True Day Night Camera - Has an removable IR cut filter, switches to Color mode and the IR Cut filter is placed over the chip to block out any Infrared (particularly useful in outdoor situations where there is alot of bush and trees), Switches to BW mode and the IR cut filter is removed. Moving parts, better color image during the day, however more chance of failure if it switches too much.

 

If its a Day Night camera it is either #1 or #2

 

Great, so it would be something like:

* Digital D/N camera - no IR cut filter, but when low light, switches to B&W

* True D/N camera - IR cut filter (also known as ICF, removable IR cut filter, whatever)

* IR camera - it can be either Digital D/N or True D/N, but with IRs

* D/N camera - all of the above

Am I correct?

 

So:

* No color cameras can be D/N (neither True or Digital)

* All IR cameras can be called D/N then, even junk IR cameras?

* There are B&W cameras with very low lux that can not be called D/N, even if they have like 0.005lux

 

This two last points are the ones that bother me. I always associated D/N cameras to "hey, this can't be crappy"...

 

-+-+-+

Ok, so checking some catalogs now, I am starting to think that cameras with IR are just never called D/N at all. So D/N cameras I think must be just the ones that switch between color and B&W at night, either with (then they are True D/N) or without ICF (then they are called Digital D/N.

 

I think this questions might look way too silly from someone in this business... I would just like to know better what I sell, and don't look stupid if I dare call something D/N, and it ends up not being D/N.

 

Thanks

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All cameras that have an ICR (Infrared Cut-Filter Removal) is called a TDN (True Day/Night) Camera whether they have IR or not.

 

All IR cameras can be a day/night cameras without having an ICR and will switch to Black and White at night, regardless of being a digital day night because of the IR's. These cameras will look different during the day because of the IR filter in front of the Image sensor. The filter stays in front permanently so it has to find the right balance of being able to filter out barely enough during the day while being IR sensitive at night. That is why you see colors that are not reproduced correctly. Since it has to be IR sensitive at night there are IR rays coming from the sun too. But if you are inside and away from the windows the colors are able to be reproduced correctly since there is no IR's from artificial lighting.

 

Color camera has a IR filter that filters the IR's to produce the correct color but is not IR sensitive so it will not pick up any IR illumination.

 

Digital Day/Night is just a color camera with the DSP taking out the color from the picture to make you believe that it is more sensitive at night. Sometimes these cameras will have an IR filter like the IR cameras without ICR but the DSP will try to correct the colors itself.

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^I couldn't have said it better myself. ICR is the factor that matters here.

 

Personally, I'm a fan of TDN. You'll have everything covered.

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What specs must it meet, if there is actually some specs to be called TDN? Or is TDN just merchandising, which manufacturers apply to their cameras as they see fit?

There isn't really a dictionary definition of "true day/night", but amongst industry professionals, as others have noted, the term DEFINITELY implies ICR.

 

Alas, without something like an FTC-enforced definition of the term, manufacturers are free to tack "true day/night" on any camera they want. So it's not really a good term to go by in the ad copy, unless it's a trusted brand name.

 

So, ICR, ICF, removable IR filter, whatever... that's what you want to look for in the specs. If they list that, or something equivalent, then you can safely tell your customers that it's a "true day/night" without looking like a shyster

 

If you really want to be sure, keep in mind that the filter in almost all TDN cameras will produce a very audible "click" when switching between day and night modes. You can test it by putting your hand over the lens to darken the scene, or if it's in a dark room, shine a bright light into it, to force it to switch... or, most will have either a switch or a menu option to force day and/or night operation; either way, you'll be able to see the display change between color and B&W, and should hear the corresponding "click".

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it now seems a TRUE DAY NIGHT is one of those things the smaller manufacturers are not testing before they ship the product out! I got 3 cameras where it didnt work, and another member on this forum got I think it was 5 from another brand! Wondering if I should start selling just panasonic for now on ... pricey but hey ... quality control must be a little better for that extra price right??

 

Thing is, those 3 bad cameras will now cost us almost the price of a panasonic box camera in a housing, as even if we save on the customs duty coming back in, we had to ship the original ones in, thats shipping within the US then much more shipping cost from the US to here, then add customs on that plus misc government fees, delivered thats double the first cost. Next we have to spend all the time on these cameras testing them to find they dont work properly, then we have to box them back up, take them to customs and fill out a form, thats more time in traffic etc, and gotta drive everywhere here to do anything at $4.30 a gallon, then pay to ship them back to the US, then pay for shipping once again back from the US to here , then pick them up again and test them again .... I mean really, wait thats MORE than a panasonic box camera in a housing! But you cant just throw away the money those 3 cost to get here .. they werent cheap, but without the IR Cut filter they were next to useless, at least for the application.

 

I mean the True Day Night cameras are great when they work .. but for how long until that IR Cut Filter mechanism fails also ... after a cut hip for the past week or so and more if you count the other crappy jobs I was stuck with, one of which hasnt paid me yet though it was completed 3 weeks ago, im starting to rethink things ... cheap Color Bullet and a dusk to dawn light (installed by their electrician) .. yeah that sounds like alot less work! Or perhaps at least wait until winter when there is alot less heat

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