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Getting Poor Night time performance with Mobotix M12

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I have a mobotix M12 D22N22 and have been quite disappointed with the night time performance. Do these require a separate IR light? Could it be that there are specific settings I need to use? Here is an example of the image I am getting: 124854_1.jpg

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That's a touch back-lit scene. Can you take a a couple pictures with a digital camera? Stand near the security camera, and take two photos, one zoomed to the brightest region outside and one zoomed to the darkest shadows inside. I'm guessing at least a dozen stops between the blown highlights and underexposed shadows.

 

Best,

Christopher

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The lux rating is as follows: B/W: 0,1 lux (t=1/60 s), 0,005 lux (t=1/1 s)

 

Chris, are asking me to take a picture of the darkest areas and lightest areas without a flash on a digital camera? If so, what are you looking to determine doing so? I appreciate the help!

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The lux rating is as follows: B/W: 0,1 lux (t=1/60 s), 0,005 lux (t=1/1 s)

 

Chris, are asking me to take a picture of the darkest areas and lightest areas without a flash on a digital camera? If so, what are you looking to determine doing so? I appreciate the help!

 

Really curios how much "better" pix you can get with 0,1 Lux

plz post final results

Thanks

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Chris, are asking me to take a picture of the darkest areas and lightest areas without a flash on a digital camera?

 

Correct, no flash.

 

If so, what are you looking to determine doing so? I appreciate the help!

 

Most digital cameras include the exposure information in the image file. If you zoom into the brightest and darkest region of the security camera field of view, we can get exposure readings of those two areas separately. Then we can compare the difference in exposure of those two regions. Looking at your posted image, I suspect you may be pushing the limits of what a security camera sensor can be expected to capture.

 

Best,

Christopher

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The lux rating is as follows: B/W: 0,1 lux (t=1/60 s), 0,005 lux (t=1/1 s)

 

Chris, are asking me to take a picture of the darkest areas and lightest areas without a flash on a digital camera? If so, what are you looking to determine doing so? I appreciate the help!

 

Digitaltrader you gave me the lux ratings of the camera just so you know Mobotix have a built in LUX meter if you could please post the reading for us. Also just so you know Megapixel cameras are not the best in low light without IR (the oen you have is one of the best). You scene is very difficult because all of the light is in-front of the camera. Your gonna need IR illumination to get the results that you are looking for.

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Digitaltrader you gave me the lux ratings of the camera just so you know Mobotix have a built in LUX meter if you could please post the reading for us.

 

The Mobotix does have a built in meter, but it meters the entire scene. I'm assuming this camera has fixed lenses and can not be zoomed. If the security camera can be easily moved forward to get two separate readings, that will work, but if a digicam is handy, it's probably easier to get the two readings using the digicam. It will be helpful if we can review the exposure at both ends (brightest and darkest) of this scene with full sunlight when the door is open.

 

Best,

Christopher

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Your gonna need IR illumination to get the results that you are looking for.

it may be a lot cheaper for him to just add a BW Exview camera for night time.

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Looking at your posted image, I suspect you may be pushing the limits of what a security camera sensor can be expected to capture.

You mean a megapixel security camera sensor right? The image i see has alot of light for a regular exview BW bullet.

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Looking at your posted image, I suspect you may be pushing the limits of what a security camera sensor can be expected to capture.

You mean a megapixel security camera sensor right?

 

No. I was referring to the large number of stops. Even cameras that support wide dynamic range will likely be challenged by this scene. A couple quick exposure measurements will give us a better idea.

 

Best,

Christopher

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No. I was referring to the large number of stops. Even cameras that support wide dynamic range will likely be challenged by this scene. A couple quick exposure measurements will give us a better idea.

 

Best,

Christopher

Going by his lux meter, a KT&C BW Exview Bullet will not be challenged at all, in fact, a True Day Night Bullet should work great also, even a non Exview BW Bullet. In Security the goal is to get the image. He can continue to worry about why this camera wont get it, count the F stops and on and on, or spend a couple little dollars and put the correct camera in for the job. Ofcourse if one is concerned about the glare from the entrance, then one would not point the camera at that to begin with.

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Going by his lux meter ...

 

Oh dear, here we go again. This can't be done with a single lux reading. It's falling-of-a-log easy for a photographer, but I don't want to fall into the trap again of trying to explain lighting issues to non-photographers. Please forget everything I said in this thread. It's way too complicated for this forum. Perhaps Soundy wants to jump in, but I'm done.

 

Best,

Christopher

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Oh dear, here we go again. This can't be done with a single lux reading. It's falling-of-a-log easy for a photographer, but I don't want to fall into the trap again of trying to explain lighting issues to non-photographers. Please forget everything I said in this thread. It's way too complicated for this forum. Perhaps Soundy wants to jump in, but I'm done.

 

Best,

Christopher

 

I agree, CCTV is obviously way too complicated for the average Photographer.

the bottom line is this, and it even a photographer should be able to understand it, a BW Exview camera will capture the image just fine. But Im not even going to bother trying to explain CCTV lighting to a photographer, just not worth the time. This forum is full of learning material though if they wish to do so.

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No. I was referring to the large number of stops. Even cameras that support wide dynamic range will likely be challenged by this scene. A couple quick exposure measurements will give us a better idea.

 

Best,

Christopher

Going by his lux meter, a KT&C BW Exview Bullet will not be challenged at all, in fact, a True Day Night Bullet should work great also, even a non Exview BW Bullet. In Security the goal is to get the image. He can continue to worry about why this camera wont get it, count the F stops and on and on, or spend a couple little dollars and put the correct camera in for the job. Ofcourse if one is concerned about the glare from the entrance, then one would not point the camera at that to begin with.

 

Rory I have to disagree with you here. A Exview will do alot better with this scene but with all of the lighting behind the object you have a hard time getting details from from the person if they are walking around in the garage. Not you mention you will have a quarter of the resolution to work with. To get the results you want add a IR illumination for the Mobotix camera or switch it out to multiple low light analog cameras.

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you have a lot to configure with the camera to get a better picture, the defaults aren't going to work with that scene -- call mobotix tech support in the morning and get transfered to international support, setup the camera for remote access by port forwarding ur router, ask tech support to checkout your camera at night and they will make changes and then tell you what they did so that you can learn

 

let me know how it goes

 

paul

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Just add an illuminator. Trust me... that will do a WHOLE lot more for you than slowing down the shutter speed. The mobotix cameras do quite well when you add some IR.

 

For example... here is a D12. This one has one color imager, and one B&W imager (the latter is IR-sensitive, of course).

 

125372_1.jpg

 

 

 

 

Here is an interior scene with little illumination... note the difference:

 

125372_2.jpg

 

 

 

 

 

Here it is with NO illumination. You can see the B&W imager is more light-sensitive, but even that's not enough in full darkness.

 

125372_3.jpg

 

 

 

 

Here is the same scene with a cheapo Ebay IR illuminator on the floor behind that chair:

 

125372_4.jpg

 

 

 

 

 

Sold on the IR light yet? I thought so.

 

Add some IR sources.... that will keep you from having to slow your shutter speed down. Slow the shutter speed enough, and you'll get blurring of any moving people or objects. Adding IR prevents you from having to make that compromise.

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The camera has the ability to set exposure zones, so you can set it to meter on the interior area instead of the broad default area. Also consider that while it's a night sensor, it's not magic, there has to be some light and I would recommed that you use an IR Illuminator or even a light on in that room is all that would be needed, maybe a 60-100 watt bulb. But if you want to overcome that outdoor light coming in, you may need some more serious lighting. Dont' be tempted to use a flourecent bulbs, it doesn't give off much IR light.

 

The M12 is a very complex camera with lots of settings for exposure, metering and such. You need to review the manual and try different settings to get the most out of it. Also, get help from their support.

 

Also, I understand that lux is a popular unit of measure used to compare cameras. From my experience, it's a totally worthless number, as useless as processor clock speed on computers, but people still use that to compare. I have Axis cameras, rated to 1 lux, and I'm lucky if I can ID someone in a room with a 60 watt bulb, the Mobotix will handle that easily.

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Lux rating is even worse than clock frequency.

 

If you try to use incandescent globe, try to reduce the voltage a little bit. lower voltage will make the spectrum of globe shift to infrared end.

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Lux rating is even worse than clock frequency.

 

If you try to use incandescent globe, try to reduce the voltage a little bit. lower voltage will make the spectrum of globe shift to infrared end.

 

If they don't quote a shutter speed with that "lux rating," it's utterly worthless.

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even the Lux rating with Shutter speed, Lens F stop, and IRE ( 15%, 30%, or 50% full scale output amplitude). it still means nothing. the manufacturer can manipulate the gains of signal. they can get any result if they really want.

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