Camera is acting strange, or is it the HUE light?

[Operations]

I have got a Philips HUE Filament E27 light next to my front door. I have also got a camera pointed right in front of that door. Recording is done by Synology (7.0.1).

That light is always on after 18.00 and goes off at 09.00. I used motion detection before (i have also got a motion sensor above my door) but that gave me a lot of short clips because of car lights / cats etc.

But something weird happens ever few minutes. It looks like the light turns a lot brighter for a second or so. But i have looked at the light and i am not seeing such a thing happen. And because of this i am still getting a lot of short event recordings on my Synology.

So i am think it is something what the camera does (adjusting the light compensation or something like that?), but i have no real clue what that would be. The camera is a Dahua dh-sd1a404xb-gnr with the latest firmware.

I have added a not really professionally created video

On the video you see the "motion detected" symbol from synology, but really the only thing that is happening is that thing with the light. So it does look like something actually happens.

But again when i look at my light from my 1st floor Window for 15 minutes i see nothing changing.

Any ideas?

 

[wittaj]

It is usually a result of the shutter speed being in concert with the frequency of the light.

Change it to manual shutter and try a different shutter speed.

 

[Operations]

It is usually a result of the shutter speed being in concert with the frequency of the light.

Change it to manual shutter and try a different shutter speed.

Have you seen the video? Does that look like what you mean? Which speed will solve this problem do you think?

 

[wittaj]

Yep. There was another thread here in the past week or so with something similar and I posted to change the shutter speed. I have seen it do the opposite and I have had cars go by with LED lights and the shutter speed is so fast and in concert with the LED lights that the headlight look off in my video. I had to adjust the shutter speed just a tad to be able to see them.

Try 1/50, 1/60, 1/100, 1/120.

If one of those don't fix it, then post screenshots of your camera settings. Backlighting options can cause it too.

 

[sebastiantombs]

Making a video on a cell phone of a video being played on that cell hone with yet another cell phone doesn't show anything constructive. Export the video as an avi or mpg and post it on Rumble or YouTube.

 

[Operations]

Yep. There was another thread here in the past week or so with something similar and I posted to change the shutter speed. I have seen it do the opposite and I have had cars go by with LED lights and the shutter speed is so fast and in concert with the LED lights that the headlight look off in my video. I had to adjust the shutter speed just a tad to be able to see them.

Try 1/50, 1/60, 1/100, 1/120.

If one of those don't fix it, then post screenshots of your camera settings. Backlighting options can cause it too.

Trying 1/75 at the moment. Will give this a few hours to see if this solved my problem. Also changed the color mode to color instead of B/W. I have got enough light now to use color.

 

[TonyR]

Seems related to issues described in an excerpt below from IPVM ==>> Light Flickering - Problem For Surveillance Cameras?

​

"Many IP cameras include an exposure setting that inhibits the tight synchronization of camera imager sensor line scanning and the native electrical distribution of AC frequency, ie:​

• 50 Hz: Common to Europe and most of Asia
• 60 Hz: Common to North America

The actual frequency of the flickering occurs at 100 or 120 Hz, as the cyclic change of AC current affects the output intensity of the lamp and is much faster than the human eye can see. However, given the fast scanning rate of the imager can sometimes be seen with surveillance cameras if the exposure point matches the wrong frequency.​

​

Many cameras include a 'flicker-free' setting that breaks the synchronization of exposures by a tiny bit (a half cycle), and this cures the issue."​

 

[wittaj]

The problem with the flicker free option is it also then eliminates some parameters that you can set as it forces the camera to not allow the user to change a parameter that can bring it back.

Anti-flicker does not allow a shutter speed faster than 1/100, nor does it allow the user to give the shutter speed a range, and does not allow a user to turn on WDR. It may take away others as well, but I know those two for sure.

The problem can be solved with a shutter speed adjustment, which is what I recommend so that a user maintains full ability to adjust camera parameters.