Ethernet Color Cameras 3.2MP vs 5MP at outdoors conditions

Hello,

Ethernet cameras are very useful when the computer is far away from camera. I’m trying to evaluate 2 different PointGrey cameras from the point of view of:

  • The quality of the image when capturing people to render it later. I would like to obtain a good quality of the body image. At least 100x300 pixels per people.
  • People is located 10m-17m far away from camera.
  • The area to play has about 9x7 squared meters.
  • Proposed Lens 16 mm ( 30º Horizontal )

Here a sketch:

Under these premises I’m wondering if there is a huge difference in terms of image quality between this 2 cameras:

https://www.ptgrey.com/blackfly-32-mp-color-gige-poe-sony-imx265-2 2
https://www.ptgrey.com/oryx-50-mp-color-10gige-sony-imx250 1

The main difference of those cameras are the resolution 3,2MP vs 5 MP.

There might be other variables that can affect to this but if you have some experience with this kind of cameras and lens, I would like to hear your opinions.

Cheers!

Hello,

I had an experience working with Sony Pregius which I found to be the best option for me. As the Sony Pregius 2nd Generation sensors are all in the same “family” meaning, they carry the same specs when it comes to Dynamic Range, Low Temporal Dark Noise, Quantum Efficiency, etc. Other than the resolutions, you also have the frame rate to consider. The 3.2MP on EVT’s 10GigE cameras for example, can go 216fps at full resolution and the 5MP 10GigE Cameras can go 163fps.

Hey ! Thanks for your replay.

I’ve seen Sony Pregious are IMX250, IMX252 (Oryx has IMX250, BlackFly has IMX265). Good to know that Dynamic Range, Low Temporal Dark Noise, Quantum Efficiency are that good :slight_smile:
I’ve a question that strongly affect affects to the quality image: If I’ve an scenario where I’ve to record video in low light conditions ( night with good streetlights around ) and a very sunny day with the same lens ( with Manual Iris ) without to change that iris.

How would you do? Is it possible to get a reasonable good quality in that extreme conditions with that IMX250? Did you ever had those conditions and get nice results?

If there is a strong issue using lens with manual Iris… Is there any compatible lens that I can use there?
I’m quite worried about this. Any tips very welcome.

My experience with ethernet camera’s has only been with low res prosilica from AVT. So, not what you would need.
My go-to USB camera is the Logitech c920 in a custom housing or lately the Logitech BRIO. https://www.kurokesu.com/shop/cameras
It allows you to add any C-Mount and CS-Mount lens.
To overcome the USB cable limit I use the BlackBox USB over Cat5 extender which give you a 100m range. https://www.blackbox.com/en-ca/store/Detail.aspx/USB-2-0-Extender---CAT5-1-Port/IC280A-R2

Since I mostly work on macOS is have had a harder time finding a good industrial camera. But recently I tested one of the Basler USB3 cams and liked it. Here is their SDK https://www.baslerweb.com/en/sales-support/downloads/software-downloads/pylon-5-0-5-osx/

1 Like

Hello Stephan!
Cameras and suggestions are very good. But then if you use a lens with manual iris at outdoors conditions you will face same issue commented, right?

Because in outdoors there is a hard difference between day and night light input. Then lens iris must be set not in best position for all both and intermediate conditions. May be I’m over thinking about this, but I guess that affect so much to the quality of the image. For dark environments image will have to be still visible ( probably a bit noisy and dark) and during daylight, a not burn resulting image. That it means 2 different light conditions where the quality of the image will not be as good as may be other professional lens can control.

That have sense? Did anyone tried cameras with manual lens for light and dark environments with manual iris? is that iris control might not be as hard issue as I’m figuring.

I don’t know how Black-magic or other cinema cameras internally does, but the difference I’m seeing is that they can get plug professional lens solutions more powerful.

Other issues that might appear: For sunny days a High contrasts of lighting for large shadows areas. I guess that can be handled by the quality of the sensor using the Dynamic Range.

Since you have a range of exposures, your best bet is to:

  1. Set your shutter length to maximum acceptable (E.g. 30ms) - note that this affects your frame rate (max frame rate at 30ms is around 30fps) - so this might suggest you use the cheaper camera since you can’t use the very high frame rates of the 10GigE camera
  2. Set your gain to an acceptable value (higher than zero, but be careful because you will be introducing noise)
  3. Point your camera at your scene at night
  4. Adjust the iris to expose the scene as you like it
  5. Lock the iris ring

Now you should have a working exposure for your night scene

For your day scene, adjust the shutter duration (and possibly gain also) in software. To do this, just turn on the Point Grey auto exposure feature.

With this method you should be able to get a good image at both day and night.

Elliot

Thanks Elliot,
Very nice to have a set of steps for a good calibration image of that. I will do it definetively! :slight_smile:

You right, sensor differences seems to not be other than resolution and Fps.

But still thinking in the 5 Megapixels against the 3.2MP. There are more pixels there to play. But I’ve to say too that are the lens here who is giving the quality to the captured area.

The resolution difference will be mostly negligible I believe.

That really depends on how much you want to spend

The more expensive one is 3x the cost
So unless you really need the specs , I wouldn’t buy the more expensive one.

You could hire a camera expert for a couple of days freelance with that money.

One thing to think about is bigger physical pixels absorb more light> you will need less gain and get less noise. The great thing about these cameras is you can change the exposure until you are lowering the frame rate. At night you can use a longer setting.

The only thing about using the iris to control light primarily (in this case using it to get as much light as you can for nighttime), is that you also limit your focal range. F 1.2 will give light has a narrower range of sharp focus.

I have gotten away with very cheap cctv lenses sometimes (the cameras are cmount) you can find cheap electronic iris models.

Thank you @elliotwoods, I will do that. That will save also in terms of network adapters too and network configurations. We had a strong 10GigE plan to extend more than the 50m in cat6a planned using media convertors to Fiber and more… FLIR says that they did not tried with Fiber and the protocol in in development, etc… but at same time It’s known that others did it, so that had to be possible. So quite dangerous network setup at the end. Good to know your opinion that almost I will not notice the difference between 3.2 and 5.0 models.

Thanks @fresla, that’s quite valuable information about how to get less noisy images in dark environments with that cheap lens. Those lens are not possible to be set to a camera if do not have that control. But I will think about it for next installations if I do not require so much resolution.

Thanks for the tips!