Nighttime colour video from a Dahua N85EFN2. Help is appreciated

[CanCuba]

This is a capture from last night with my Dahua N85EFN2 4K Night camera with a 2.8mm focal length. Looking to tweak as much as possible. I will be using this camera to direct a mini-PTZ SD1A404XB to do facial detection along the sidewalk and front entrance. The PTZ will be mounted in the corner underneath the terrace.

I'm doing this to monitor who passes in front of my house with a tripwire activated between 10pm and 6am. There's been a lot of thefts in the surrounding blocks and I'm working with some neighbours to find out who has been circulating when said thefts happen in order to see a pattern. We're sure it's a local group of youths who are semi-organized.

This camera doesn't need to identify (I knew that when buying the camera) as the PTZ will be doing the zooming and face detection.

When doing the screenshots of the settings, I realized that WDR was on. And the gain is probably high.

It's illuminated a 120W LED reflector (equivalent to about 1000W incandescent). I'll be replacing it with a much more powerful unit, about 3X more powerful, to be able to simulate daylight as much as possible.

Forgot to screenshot the image settings but here they are:

Coding Strategy: General
Type: General
Compression: H.264
Resolution: 3840x2160(4K)
Frame Rate(FPS): 10
Bit Rate Type: CBR
Bit Rate(kb/S): 8192

Any help is greatly appreciated.

View attachment NVR_ch1_main_20221017210540_20221017210623.mp4

 

[ludshed]

Try different backlight settings.

DahuaWiki

dahuawiki.com

 

[wittaj]

You shouldn't use backlight at night. It will cause issues. Or if you do, go as low as possible. 50 will cause problems.

 

[CanCuba]

Try different backlight settings.

DahuaWiki

dahuawiki.com

Where should I start? I've tried BLC but I find WDR works the best. Right now, I have it set to SSA but the camera won't tell me which backlight setting it's deciding to use! A bit frustrating.

 

[CanCuba]

You shouldn't use backlight at night. It will cause issues. Or if you do, go as low as possible. 50 will cause problems.

Ok, I'll give that a go tonight. Wife is losing her patience with all this tweaking of the cameras.

Hoping to have the 500W reflector to replace the 150W I have right now. Illumination is always better than trying to compensate for lack of the same, no?

 

[wittaj]

Yeah, people are used to the just hang them up consumer grade cameras like Ring and Nest and Arlo, but that simplicity comes at the cost of usable images with motion.

So it takes some time tweaking the settings to your field of view.

And yes illumination is always better than trying to compensate for lack of light!

In your example, with a gain of 75 and WDR at 50, motion will be a blur and useless.

 

[CanCuba]

Been occupied with the mini-PTZ which only needs the IR illuminators mounted to do nighttime face detection.

Took @wittaj 's suggestions.

This video (which has a small defect) has a bit more light from a LED reflector, no backlight, faster shutter, less gain. I think it's an improvement.

7m (23 feet) above the road and about 7m (23 feet) back on a 2.8mm lens. Not ideal but this is being used mainly as a spotter cam now.



View attachment NVR_ch1_main_20221201202224_20221201205424.mp4

 

[Don't Look Up]

You might try Auto Gain Control and set from 0-100 for your Night profile.

 

[CanCuba]

You might try Auto Gain Control and set from 0-100 for your Night profile.

I'll give it a shot. It would be nice to see what shutter and gain the camera is running at any given time. Just to get an idea of how it's adjusting the settings.

 

[toastie]

I'm using a similar camera covering the back garden, it's a DH-SD1A404XB-GNR, and like you I might explore having it configured as a spotter camera. It runs firmware 2.812.0000032.1.R, Build Date: 2022-06-24 and the settings for illuminator are the options, Manual, ZoomPrio, SmartIR and Off. As the camera also provides IR illumination for an adjacent PTZ camera I found the ZoomPrio gives the best illumination.

What I only get at night with this camera are B&W images, the adjacent Dahua PTZ will switch to color when our kitchen lights are turned on, and I think too if bright halogen floodlights are triggered by a PIR detector, this small PTZ stays on B&W until daylight.

 

[CanCuba]

I'm using a similar camera covering the back garden, it's a DH-SD1A404XB-GNR, and like you I might explore having it configured as a spotter camera. It runs firmware 2.812.0000032.1.R, Build Date: 2022-06-24 and the settings for illuminator are the options, Manual, ZoomPrio, SmartIR and Off. As the camera also provides IR illumination for an adjacent PTZ camera I found the ZoomPrio gives the best illumination.

What I only get at night with this camera are B&W images, the adjacent Dahua PTZ will switch to color when our kitchen lights are turned on, and I think too if bright halogen floodlights are triggered by a PIR detector, this small PTZ stays on B&W until daylight.

The red arrow is pointing at my own SD1A404XB! Great little camera. I have a post about it's face detection capabilities. Quite impressive and a much more subtle form factor than the "death star" PTZ cameras. Even I look directly at it, I have a hard time figuring out which way it's pointing. I'm sure few people even realize it's a PTZ.

I will mount it lower down on the column when I have the proper mounting hardware. Living in Cuba means I have to have friends and family bring stuff down to me if I'm not traveling myself.



I'm waiting on two IR illuminators to be delivered to me. Going to keep the PTZ in B/W in the night settings and flood both the sidewalk and street with IR. I've gotten some decent captures at night but far, far lower percentage than daytime. Daytime I'd say I get 70% of the people that pass by. Over 500 face captures a day on Instant Snap setting with the lowest quality set.

This night colour camera and a few others do the spotting work for the PTZ. PTZ swings in and does its thing. Can't say enough about this camera.

I know I'll never get Identity-quality video at night off the N85EFN2 but I'd like to keep tweaking it.