1/3" CMOS @ 4 MP versus 1/2.7 @ 5 MP - I have questions

sebastiantombs said:
That's a CVI, composite video information, camera in the "Lite" series. Look at the minimum illumination spec of .001 LUX. A 5442, 4MP camera and a PoE camera, has a minimum LUX rating of .002. The spec saying 5MP for the sensor says nothing about how big it is.
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just to understand; if the minimum illumination is low, it means that the camera can handle better at night time (avoiding other camera's parameters)? - if this correct, then 0.001 is better (in that sense) than 0.002?
 
Yes, it is in theory but even Dahua exaggerates these specs at times. The only true way to know would be a side by side comparison under the exact same lighting conditions. I'd also speculate that since the video source from that camera is composite something will be lost when it is digitized for viewing on a PC.
 
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just peeping in real quick. The IPC-HFW5849T1-ASE-LED (Color 4K-X), a POE camera, has a lux rating of .0005 !
Many factors better in seeing in very dim light than .001 or .002

Sorry! I will butt out : )
 
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HFW3449T1N-AS-PV 1/2.7 @ 5 MP
Because 5MP is a 20fps 4:3 picture
So I prefer 4MP 30fps 16:9
daytime.jpg


Night.jpg
 
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You must be producing a Hollyweird Epic and a half at 30F/ps. Even Hollyweird only uses 24F/ps. Shutter speed, exposure, is the real key.
 
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wittaj said:
A few tips....It is simple LOL 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.

You are looking at 3 budget cams, which use lessor quality material and sensors to sell a MP that the uninformed general public thinks they want. As an example, unfortunately, most 4k (8MP) 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). Starlight, ColorVu, Full Color, etc. are simply marketing terms, so don't be sold on those names.

Sensor sizing can confuse a lot of people LOL.

It is simple division:

1 divided by 3 equals 0.333

1 divided by 2.8 equals 0.357

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:

View attachment 115403


The 3 cameras you reference above are considered budget cameras. The 2431 will only be recommended for those on a super tight budget, but for not much more a better 2MP or the 4MP 5442 series would be the better bet. The dome should be avoided for outdoors - you get glare, rain drops that stick to it, dust, etc.

Stay away from those 5MP. Ideal sensor size is:

2MP = 1/2.8"
4MP = 1/1.8"
8MP = 1/1.2"

So simply doing a ratio, a 5MP would need a 1/1.65" sensor to be comparable, and we just do not see a 5MP on a sensor any larger than 1/2.7".

A 2MP on the 1/2.8" sensor will kick the but of your 3 referenced cameras all night long. That 4MP will need over double the light of the 2MP at night.

How many of the reviews that you saw on those 5MP cameras were based on motion at night? Any camera can be made to give a great static image and all the Amazon reviews on those cameras are based on that.

The budget cam will make for an ok overview camera, but you shouldn't expect IDENTIFY capabilities from it in most instances.
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Can I use this simplification of sensor size on my business webpage? :)
#1 question I get when talking about installing Dahua cameras is the sensor size. It's hard to explain, but you make it sound easy to understand.
 
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