Filter size

[JesseSR]

Hello... Help me understand a few things regarding filter size on a camera. (EDIT: SENSOR SIZE! not filter size, lol, ugh)

What does 1/1.8 " or 1/2.5" or 1/2.7" actually mean? Is there a picture I can reference to understand what it really means and why one is better than the other and how it effects things like the cameras CPU ability to process AI, how it relates to MP of the camera, or how it handles day/night picture

As I understand it, the smaller the # the better... ex: a 4MP with a 1/1.8" seems to be better than a 5MP with a 1/2.7" filter. or, a 8MP camera with a 1/2.7" is way worse than a 8MP with a 1/1.8" and a 1/1.2" would be even better ... but what I don't understand is the "why", yet. (I tried searching for info on this, but it's a hard term to search for on the forum, and @wittaj explained it to me once, but I admit I've since forgotten the reasoning behind it)

In short, I have had a BUNCH of problems with this particular camera for nearly 6-8 weeks now: DahuaWiki and have decided to replace all of them with IPC T5442T-ZE cameras from @EMPIRETECANDY which I bought 6 of last night. I'm losing some extra features by making the swap but I need IVS reliability and so far, the N55DU82 reliability for IVS has been completely awful. My initial IVS tests with the (1) IPC T5442T-ZE camera I bought earlier this week had much better reuslts with IVS rule consistency than the IVS consistency of the N55DU82, even thought the N55DU82 is a much more expensive camera (so I assumed better, but definitely not better specifically related to IVS).

I really thought it was me at first and my lack of knowledge (I'm really ignorant to sooo many things I read here still). But thanks to @wittaj for the assistance and spending time looking at the N55DU82 cameras with me and validating that the IVS capabilities of the N55DU82 are horrible and terribly inconsistent. (I think even he was surprised). So basically I decided to swap them out with a proven camera model that works well with IVS rules.

I also have 3 expensive ($800) thermal cameras that I still might need to replace with something else because they don't work so hot either and IVS on them is inconsistent too, plus they have numerous bugs that I have L2 cases open with Dahua and Dahua HQ. But, I'm holding off replacing those thermals, for now at least. First things first and address the non-thermals...

Anyway, sorry for babbling, main point is, help me understand filter sizes per MP, etc. ! thanks!

 

[wittaj]

It is a sensor, not a filter LOL, but sensor sizing can confuse a lot of people LOL.

Is a 1/2.8" sensor bigger than a 1/1.8" sensor? Most people say yes LOL. But it is a fraction, so the 1/1.8" sensor is the bigger of the two.

This applies to camera sensors too LOL:



@sebastiantombs breaks it down quite nicely:

1/3" = .333" Great for 720P
1/2.8" = .357" (think a .38 caliber bullet) Great for 2MP
1/1.8" = .555" (bigger than a .50 caliber bullet or ball) Great for 4MP
1/1.2" = .833" (bigger than a 20mm chain gun round) Great for 8MP

Aging computer problems, possible processor recommendations?, noob problems with Blue Iris

Hello everyone, great to be here. Just started using Blue Iris, have some problems and questions for you all. 1. So anyway, Im using an I7 2600k processor with a 970 Nvidia GTX graphics card, it's a retired PC I built myself for gaming, and brought out of retirement to run Blue Iris. My...

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[MikeLud1]

Hello... Help me understand a few things regarding filter size on a camera.

What does 1/1.8 " or 1/2.5" or 1/2.7" actually mean? Is there a picture I can reference to understand what it really means and why one is better than the other and how it effects things like the cameras CPU ability to process AI, how it relates to MP of the camera, or how it handles day/night picture

As I understand it, the smaller the # the better... ex: a 4MP with a 1/1.8" seems to be better than a 5MP with a 1/2.7" filter. or, a 8MP camera with a 1/2.7" is way worse than a 8MP with a 1/1.8" and a 1/1.2" would be even better ... but what I don't understand is the "why", yet. (I tried searching for info on this, but it's a hard term to search for on the forum, and @wittaj explained it to me once, but I admit I've since forgotten the reasoning behind it)

In short, I have had a BUNCH of problems with this particular camera for nearly 6-8 weeks now: DahuaWiki and have decided to replace all of them with IPC T5442T-ZE cameras from @EMPIRETECANDY which I bought 6 of last night. I'm losing some extra features by making the swap but I need IVS reliability and so far, the N55DU82 reliability for IVS has been completely awful. My initial IVS tests with the (1) IPC T5442T-ZE camera I bought earlier this week had much better reuslts with IVS rule consistency than the IVS consistency of the N55DU82, even thought the N55DU82 is a much more expensive camera (so I assumed better, but definitely not better specifically related to IVS).

I really thought it was me at first and my lack of knowledge (I'm really ignorant to sooo many things I read here still). But thanks to @wittaj for the assistance and spending time looking at the N55DU82 cameras with me and validating that the IVS capabilities of the N55DU82 are horrible and terribly inconsistent. (I think even he was surprised). So basically I decided to swap them out with a proven camera model that works well with IVS rules.

I also have 3 expensive ($800) thermal cameras that I still might need to replace with something else because they don't work so hot either and IVS on them is inconsistent too, plus they have numerous bugs that I have L2 cases open with Dahua and Dahua HQ. But, I'm holding off replacing those thermals, for now at least. First things first and address the non-thermals...

Anyway, sorry for babbling, main point is, help me understand filter sizes per MP, etc. ! thanks!

Checkout the below post

Sensor Size Chart

 

[wittaj]

For those interested, the N55DU82 is a 5MP on a 1/2.7" sensor and I tried every trick I know to try to make the IVS reliable and nothing worked. Tripwires, zigzags, intrusion boxes, changing settings and tweaking to the field of view and it would work like half the time. He put a 5442 in its place and it triggered every time!

I think it is another one of the cameras with too much going on and maxing out the CPU and it misses.

 

[wittaj]

Put a 2MP and 4MP and 8MP on the same size 1/2.8" sensor and the 2MP will kick the 4MP and 8MP all night long.

The 4MP will need double the light and the 8MP will need quadruple the light to produce the same image at night.

An analogy to try to understand why cameras need so much more light - let's look at a 4MP camera and this 4MP needs at least twice the amount of light as a 2MP at night for the same sensor. The sensor size is the same in each camera, but when you spread the "screen" of 4MP worth of pixel holes across the same sensor, it now has double the holes, but also double the "screen material" than the 2MP. A 4K camera would need 4 times the light of a 2MP or double the light of a 4MP for the same sensor.

Kind of hard to explain, but lets try to use a window screen as an analogy - take a window where the opening is fixed - that is the sensor - you add a screen to it (that represents 2MP) and looking out through the screen is a little darker because of the screen material. Now replace that screen with one that has double the holes (now it represents 4MP) and it will be darker looking through it because (while the resolution would be better) there is more screen material. At night time, look out your window with and without the screen and it will be darker looking through the screen than without it. If you are looking out your window to see the stars or the moon, do you look out the part of the window with the screen, or the upper portion without the screen material? Now obviously as it relates to a camera, you need to balance the amount of pixel holes with the screen material - too few holes (and thus less screen material) and the resolution suffers, and too many holes (and thus more screen material) and the more light that is needed.

It is why many of us here say do not chase MP - do not buy a 4MP camera that is anything smaller than a 1/1.8" sensor. Do not buy a 2MP camera that is anything smaller than a 1/2.8" sensor. Do not buy a 4K (8MP) camera on anything smaller than a 1/1.2" sensor. Unfortunately, most 4k cams are on the same sensor as a 2MP and thus the 2MP will kick its butt all night long as the 4k will need 4 times the light than the 2MP... 4k will do very poor at night unless you have stadium quality lighting (well a lot of lighting LOL). At nighttime is when most of us want the camera to perform. Almost any camera can work with enough daylight.

2MP on 1/2.8" or bigger
4MP on 1/1.8" or bigger
8MP on 1/1.2" or bigger

If it doesn't meet that, then don't buy.

 

[Flintstone61]

 

[EMPIRETECANDY]

@JesseSR thanks for your support, if you want a camera support siren and speaker, can add 1-2 more cams to your system, IPC-Color4K-X is the best choce, 4K full color, build in 2 way audio, sure with siren too.
For the cmos size @wittaj and @MikeLud1 has posted the right answers.

 

[JesseSR]

So based on all this... Sensor size versus MP makes a very big difference in picture quality for day and especially at night. How does it relates to CPU of the camera? Assuming 2 cameras have the SAME CPU.. one camera is a 4MP 1/1.8" and another is a 5MP 1/2.7" , why would the 5MP camera's camera struggle more and as a result have less reliable IVS settings etc. Because the CPU is having to work harder on the image quality in the first place?

 

[JesseSR]

@JesseSR thanks for your support, if you want a camera support siren and speaker, can add 1-2 more cams to your system, IPC-Color4K-X is the best choce, 4K full color, build in 2 way audio, sure with siren too.

@EMPIRETECANDY
Yes, I -may- eventually replace the (7) 5442s that I just bought from you this week, with the newer 4K models , but I need the cameras ASAP, and want the 2.7mm one which you won't have stock for in a little while, so I had to go with the 5442s due to urgency, -and- I want to wait a little longer for some firmware bugs to get resolved on the 4K units... But i definitely plan on buying them in the future. For now, the IPC-T5442's I just bought from you have -PROVEN- reliable IVS and good night time vision as well, so I'm using those (for now) to replace these disappointing N55DU82's from Dahua.

Also I need to talk with you offline (DMs?) about problems I'm having with these 3 thermal cameras I bought from Dahua: (wittaj might have told you about them)
--DF1241N-D2F2
--DF1241N-D7F8
Both are having issues with 1) poor IVS reliability (case # 0130054201 and also separate issues with NOT sending DMSS push notifcations and 2) not logging AI-Search recordings in my DVR for successful IVS triggers.. (case # 0130051673). BOTH cases have been escalated with Level 2 Dahua support AND even with HQ... and I still have no resolution for them. So I MAY replace those cameras too if they can't fix the firmware bugs for either case.

 

[wittaj]

So based on all this... Sensor size versus MP makes a very big difference in picture quality for day and especially at night. How does it relates to CPU of the camera? Assuming 2 cameras have the SAME CPU.. one camera is a 4MP 1/1.8" and another is a 5MP 1/2.7" , why would the 5MP camera's camera struggle more and as a result have less reliable IVS settings etc. Because the CPU is having to work harder on the image quality in the first place?

Yes, typically when you see a mismatch of MP to sensor combo, like a 5MP on a 1/2.7" sensor, that means they are trying to keep costs down and probably essentially have the same CPU in that unit as a 2MP on the same size sensor. And then you see the other items that the 5MP added to that camera - to fit it all in, they skimp on CPU.

Keep in mind that these type of cameras and NVRs, although are spec'd and capable of these various parameters, real world testing by many of us shows if you try to run these units at rated "specs" that you will max out the CPU in the unit and then it bugs out just long enough that you miss something or video is choppy. My car is rated for 6,000RPM redline, but I am not gonna run it in 3rd gear on the highway at 6,000RPM...same with these types of units - gotta keep them under rated capacity. Some may do better than others, but trying to use the rated "spec" of every option available is usually not going to work well, either with a car or a camera or NVR.

 

[wittaj]

The camera that comes to mind for me is the "booby cam" AKA as HDBW4231F-E2-M. It is a camera that has two cameras on it.

It works great as an overview cam - you can place it on the corner of the house and see down two sides with one cam, or many put this at the front door to see people with one, and delivery boxes with the other.

But the CPU in it cannot keep up and IVS only works with one of the cameras It is basically trying to process two 2MP cameras on the same CPU as one 2MP camera (so I suspect it would be similar to this CPU trying to process 4MP or more) - cannot do both at the same time and it really struggles when the SD card gets full.

But it is still a great camera and fills in a great niche. I have two of these and certainly recommend them for the right location.

Since I use Blue Iris, the two factors the camera suffers from isn't as critical as it might be for others.

Dahua is coming out with a 4MP version that has beefed up the camera to allow for IVS on both cameras!

 

[EMPIRETECANDY]

The size of the sensor actually refers to the area of the photosensitive device, and CMOS is included here. The larger the area of the photosensitive device, the larger the area of the CMOS, the more photons captured, the better the photosensitive performance, and the higher the signal-to-noise ratio

 

[EMPIRETECANDY]

@EMPIRETECANDY
Yes, I -may- eventually replace the (7) 5442s that I just bought from you this week, with the newer 4K models , but I need the cameras ASAP, and want the 2.7mm one which you won't have stock for in a little while, so I had to go with the 5442s due to urgency, -and- I want to wait a little longer for some firmware bugs to get resolved on the 4K units... But i definitely plan on buying them in the future. For now, the IPC-T5442's I just bought from you have -PROVEN- reliable IVS and good night time vision as well, so I'm using those (for now) to replace these disappointing N55DU82's from Dahua.

Also I need to talk with you offline (DMs?) about problems I'm having with these 3 thermal cameras I bought from Dahua: (wittaj might have told you about them)
--DF1241N-D2F2
--DF1241N-D7F8
Both are having issues with 1) poor IVS reliability (case # 0130054201 and also separate issues with NOT sending DMSS push notifcations and 2) not logging AI-Search recordings in my DVR for successful IVS triggers.. (case # 0130051673). BOTH cases have been escalated with Level 2 Dahua support AND even with HQ... and I still have no resolution for them. So I MAY replace those cameras too if they can't fix the firmware bugs for either case.

Yes, just send me emial kingsecurity2014@163.com for the thermal cam, i will get a super engineer for you from dahua.
Those IPC-T5442T-ZE is the best cam we have now.