Adjusting camera exposure.

NorthBendDave

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I have a Lorex NVR system that I added a Dahua T5442T-ZE. I had an incident this morning and realized I REALLY need to make some camera adjustments. The Lorex system NVR does NOT have the Internet explorer icon to access the camera.
Do I need to pull the cams and connect through a switch to access them?

After my last incident, I bought the Dahua cam from Andy. Way better cam than the Lorex I had.

Night vids are still bad. Dahua cam always stays color due to the ambient lighting.

In the close picture the guy is only 10' from the camera (cam is 8' high) Subject is not identifiable.

The picture of the van looks like it is a Ford with a ladder rack on top. Looks like the driver door and fender are a different color
 

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sebastiantombs

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The camera looks like it's still on auto for all settings. You need to go into the web GUI for that camera and make some adjustments, get everything off of auto like exposure and such. Set the shutter to manual and the slowest you can go is 1/60 in night mode. Slower than that will produce blur. Gain end exposure compensation may also need to be reduced or upped depending on the situation but when too high will introduce noise and blur. Test every change you make by walking around the FOV of the camera. You may find that you have to switch to B&W at night even with your ambient lighting. Every situation is different.

I don't use an NVR so no real solid advice on how to access the camera. Some NVRs will let you in through the LAN pot, not all, and you will need the IP of the camera no matter how it's finally accomplished.
 
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wittaj

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All settings are done within the camera GUI.

it comes down to configuring your camera and dialing it in to your field of view and using a test subject to walk around while you are adjusting.

Auto/default settings are usually going to be problematic. Auto shutter at night was probably a motion blur ghost and didn't look like a human.

And some field of views will be problematic as well. YMMV.

In my opinion, shutter (exposure) and gain are the two most important and then base the others off of it. Shutter is more important than FPS. It is the shutter speed that prevents motion blur, not FPS. 15 FPS is more than enough for surveillance cameras as we are not producing Hollywood movies. Match iframes to FPS.

Many people do not realize there is manual shutter that lets you adjust shutter and gain and a shutter priority that only lets you adjust shutter speed but not gain. The higher the gain, the bigger the noise and see-through ghosting start to appear because the noise is amplified. Most people select shutter priority and run a faster shutter than they should because it is likely being done at 100 gain, so it is actually defeating their purpose of a faster shutter.

Go into shutter settings and change to manual shutter and start with custom shutter as ms and change to 0-8.3ms and gain 0-50 (night) and 0-30 (day)for starters. Auto could have a shutter speed of 100ms or more with a gain at 100 and shutter priority could result in gain up at 100 which will contribute to significant ghosting and that blinding white you will get from the infrared.

Now what you will notice immediately at night is that your image gets A LOT darker. That faster the shutter, the more light that is needed. But it is a balance. The nice bright night image results in Casper during motion LOL. What do we want, a nice static image or a clean image when there is motion introduced to the scene?

So if it is too dark, then start adding ms to the time. Go to 10ms, 12ms, etc. until you find what you feel is acceptable as an image. Then have someone walk around and see if you can get a clean shot. Try not to go above 16.67ms (but certainly not above 30ms) as that tends to be the point where blur starts to occur. Conversely, if it is still bright, then drop down in time to get a faster shutter.

You can also adjust brightness and contrast to improve the image.

You can also add some gain to brighten the image - but the higher the gain, the more ghosting you get. Some cameras can go to 70 or so before it is an issue and some can't go over 50.

But adjusting those two settings will have the biggest impact. The next one is noise reduction. Want to keep that as low as possible. Depending on the amount of light you have, you might be able to get down to 40 or so at night (again camera dependent) and 20-30 during the day, but take it as low as you can before it gets too noisy. Again this one is a balance as well. Too smooth and no noise can result in soft images and contribute to blur.

Do not use backlight features until you have exhausted every other parameter setting. And if you do have to use backlight, take it down as low as possible.

After every setting adjustment, have someone walk around outside and see if you can freeze-frame to get a clean image. If not, keep changing until you do. Clean motion pictures are what we are after, not a clean static image.
 

NorthBendDave

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Thanks for the replies. My front door cam saw most of his activity under the carport. Funny, he picked up a gas can but it was empty....But it recently had 3 gallons of waste antifreeze in it. Would have served him right.
I think I'll try the firmware update, and if it bricks I must have needed a new one anyway.
 
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