Why do "high end" cameras use a 1/2.8" sensor?

[Garrik]

Been reading the excellent posts here on resolution/pixel count vs. sensor size. Makes total sense.

Until you realize that all of the "high end" cameras from companies like Axis and Hanwha use 1/2.8" sensors in all of their cameras, even their X series 4K cameras.

Does anyone know why that is? ie why do these 5MP and 4K ~$2k cameras from very well known brands use 1/2.8" sensors instead of larger ones?

 

[steve1225]

Both Hanwha and Axis have higher models with 1/1.8" sensor, Axis have 1/1.2" and is going even to 4/3" in one model..
Hanwha X is only higher (PRO) line , Hanwha P line is high-end one..

bigger sensors require much bigger optics which require much bigger chassis - so they usually limited to higher lines..
Also big PRO CCTV companies do classic CCTV where at night You simply use IR and black&white mode..

Night Full Color thing is specific for Chinese brands (Hik/Dahua/Uniview)...

 

[Garrik]

RIght you are - my mistake and apologies. Axis P1468 for example, 4k camera with 1/1.2" sensor, or Q1808 with a 4/3" sensor. I should have searched harder.

"Also big PRO CCTV companies do classic CCTV where at night You simply use IR and black&white mode.. Night Full Color thing is specific for Chinese brands (Hik/Dahua/Uniview)..."

Can you say more about this please? Do these "high end" Axis and Hik cameras not support color at night? Do they force black and white?

 

[steve1225]

RIght you are - my mistake and apologies. Axis P1468 for example, 4k camera with 1/1.2" sensor, or Q1808 with a 4/3" sensor. I should have searched harder.

"Also big PRO CCTV companies do classic CCTV where at night You simply use IR and black&white mode.. Night Full Color thing is specific for Chinese brands (Hik/Dahua/Uniview)..."

Can you say more about this please? Do these "high end" Axis and Hik cameras not support color at night? Do they force black and white?

Color at night is very tricky. Even with large sensors, big open apertures (not sharp image) and AI image processing.
in most cases we can have good results with static image but mediocre - semi good with people/cars in motion.

In comparison IR simply works - and you can have sharp not blurred image on people / cars in motion.. But You have BW image and IR reflections...

so all CCTV companies do 95% models in normal 1/2.8" image sensor - which is handy size to put matched optics in small chassis. And they are designed to work with IR at night...

Cams which worked in color mode at night are thing created first by Dahua (Starlight with Sony Starvis sensors) then HIK & UniView..
Then both HIK and Dahua developed first generation of ColorVu / Full color cams with fully open aperture and white light..

ps. this forum is very specific in religion (yes religion!) to big image sensors 1/1.8" or 1/1.2", better resolution/sensor size ratios, using different focal lengths (zoomed optics)...
95% of cctv market today (by sales volume) is targeting into 8Mpx 1/2.8" image sensor on 2.8mm fixed lenses..

 

[Garrik]

...this forum is very specific in religion...to big image sensors...better resolution...different focal lengths...

Yep, figured that out on the first day lol And generally speaking, all of that makes good sense to me (I am an engineer, and quite technical).

I do think that for me, there are a bunch of other factors at play - build quality (plastic vs metal), lens quality (plastic vs. glass), software (ease of use, features, reliability, integration standards compliance), etc. But my "plan" is to evaluate a bunch of cameras and then design my "ultimate" system. I will kick off a separate thread to track that project.

 

[tangent]

Been reading the excellent posts here on resolution/pixel count vs. sensor size. Makes total sense.

Until you realize that all of the "high end" cameras from companies like Axis and Hanwha use 1/2.8" sensors in all of their cameras, even their X series 4K cameras.

It's also worth remembering that the image sensors in most of these cameras are made by 4 or 5 companies. The SoC that they pair with various sensors varies as does the software and some cheap manufactures cameras aren't very reliable.

There are downsides to the larger sensors: higher cost, lower depth of field, and larger cameras. If you've flown anywhere in the last couple years you've probably seen some very high end high resolution cameras at airports in very well lit areas like security.