cglaeser

Excellent! Thanks for posting this. Do you by chance have access to a photography light meter? I know the Mobotix is reporting reflected lux values, but it would be great if we could independently measure the ambient lux value. Best, Christopher

Right, we agree, the banding is not due to high gain. That's why I provided a different explanation than your original answer. Take another close look at the sunlight photo of the car. Look at the high contrast diagonal parts of the car wind shield and front bumper. See those horizontal bands near the high contrast transitions? Those bands do not appear in the SEC model, and yet, here they are in the IT model, which uses the same sensor. I'm suggesting those bands were introduced by the firmware when the megapixel image was reduced to a VGA image, and at night, those bands are amplified by the high gain. I asked Mobotix tech support and they confirmed it. Best, Christopher

Have you actually tried to identify someone.? That chair is not moving. It's important to keep in mind that many of these IP cameras will automatically adjust the exposure time to as long as 1 or 2 seconds. Try walking across the room in total darkness and see if your face is as sharp as the chair, or is it just a blur. Regarding the car at 35 mph, that's daylight, when the shutter speed could be 1/100 or faster. You need to test moving objects in total darkness and then post those images. Best, Christopher

No doubt the high gain is causing the high noise, but it's possible the firmware could be contributing to the horizontal banding. The IT uses the same sensor as the SEC, and the megapixel image is converted to VGA in firmware. If the algorithm uses a relatively simple approach of combining pixels along a horizontal row, that would introduce banding. BTW, that's why the IT and SEC have identical minimum illumination specs. They use the same sensors. Best, Christopher

Please test the LED in total darkness using a reasonable shutter speed (1/30 or faster). Best, Christopher

No doubt the dedicated B/W lens is a big help for the M12D. The Axis 223M can not come anywhere close to this performance. I would estimate it requires at least 7 stops more light. Each stop is 2x, so 7 stops is 128x more light. Or, approximately 0.1 lux in 2 seconds. Two second exposure time is an eternity when someone is walking; subjects are just a wispy blur. Would love the opportunity to measure the M12D SEC in low light. Best, Christopher

The Axis 223M megapixel day/night security camera has a minimum illumination of 0.2 lux at f/1.4 listed in the technical specifications. However, the technical specifications fail to mention the shutter speed (exposure time) used to measure that minimum lux value. Using a photography light meter under a street light at night near my house, I measured a light value of ISO 3200, 1 second, f/8. Using a table I located on the net, this corresponds to EV 1 or 5 lux. Objects under the street light look very good on the 223M if the shutter speed is set to 1/2 second, and look poor and grainy at 1/6 second (the camera does not have any settings between 1/2 and 1/6). A light value of 0.2 lux is between 4 and 5 stops less light than 5 lux (reducing light by one stop reduces the lux value by half). This means that Axis exposure time must be increased 4 to 5 stops to compensate for the reduced lux value (my lens is zoomed about half way, so that could account for one full stop there). Although the Axis brochure does not mention the exposure time required for the 0.2 lux rating, this analysis, if done correctly (please check my math) means Axis used the longest supported exposure time of 2 seconds to measure that 0.2 lux value. In other words, a stationary building and a parked car look great on the Axis 223M at 0.2 lux. However, if you want to recognize people who are walking and otherwise moving at normal speed, 1/25 is pretty much a minimum requirement, and 1/60 would be considerably better. Of course, using a shutter speed of 1/60 requires considerably more light than 0.2 lux. These values seem very far from the product specs for the Mobotix M12D which claim 0.1 lux at 1/60 (is this for both the IT and SEC? It's not clear from the brochure). The Mobotix has both a larger sensor and a sensor specifically designed for B/W low light use, so that could account for the large difference. 0.1 lux at 1/60. That seems pretty remarkable. Does anyone have access to a Mobotix SEC M12D and a light meter? Comments? Please check my analysis and math. Best, Christopher

IP cameras often contain a processor capable of motion detection. Why is auto tracking so rare in IP PTZ cameras? A good example is the Axis 215, which appears to be a fine compact PTZ, but does not include auto tracking. Although auto tracking could be done by the server, the lag time and increased load on the server make this a less-than-ideal solution. And, it's not like these vendors have not already solved this problem in another model (e.g. Axis 233D supports auto tracking). Why isn't this code/feature included with other models? Best, Christopher

Thanks for bringing that to my attention, I missed that. That explains the excellent low-light photo (I thought it was a down-res'd megapixel). I'm interested in the SEC model. Would be interesting to compare the night photos of the SEC. Best, Christopher

The M12D has two sensors and both have considerably more pixels than VGA. Take a look at the purple fringing and CA. Best, Christopher

Have you seen exceptionally good photos from a high-quality digital camera posted on the internet? The camera may be 10 megapixel or more, and then the resolution is reduced to VGA sized to fit on a web page. Photos taken with a high megapixel that are then down-resed typically look much much better than photos taken with low-end cameras with only a modest number of pixels. There are other factors as well. Cheaper cameras not only have fewer pixels, but the pixels themselves may be very small, which means they collect less light and have more noise. In addition, high-end cameras typically have multi-element glass lenses, whereas low-end cameras may have plastic lenses. Best, Christopher

I am especially interested in the shutter speed (exposure time) used at night. The 223M produces great images of my driveway at night using a 1 or 2 second exposure time, but even very slow moving objects are just a blur at that setting. Please post your observations and images when available. I placed an order for a RayMAX 50 Fusion IR Illuminator. No word yet on when it is due to arrive, but looking forward to using the 223M with an illuminator. Also, where did you get the M12D? The Mobotix website has a list price of something like $1,195, but I have not seen them for sale on the net for that price. Did you get a loaner for testing? Would love to get a loaner myself. Regarding the M12D form factor, I agree, I like the design compared to the standard CCTV enclosure. The M12D would blend in pretty well with the front of my house without too much clutter. Best, Christopher

Just a very quick stab at this, but what are the IP addresses of all 10 cameras? Did you manually set the IP address of each camera, or is each IP address assigned via DHCP? If two or more cameras have the same IP, that could cause problems. Best, Christopher

Here are some low light specs from the two cameras. Axis 223M 1/2.7" sensor B/W 0.2 lux F1.4 Mobotix M12D 1/2" sensor B/W 0.1 lux 1/60s F2.0 B/W 0.005 lux 1/1s F2.0 - The M12D has two sensors, one each for day and night. The 223M has one sensor with an IR cut filter to cover both day and night. - The M12D sensor is much larger than the 223M sensor, and thus has the potential for better low light characteristics, everything else being equal. - The 223M specs do not indicate the shutter speed (exposure time). The camera is capable of a 2 second exposure time. Since they do not include the exposure time used to measure the low-light lux level, it's not clear if they used an excessively long 2 second exposure time or a more realistic 1/30s exposure. The M12D specs list the lux levels for two exposure times (all manufacturers should list at least one exposure time for the data to be meaningful). - The M12D has five fixed lenses from which to choose. The aperture on all the lenses is F2.0 except the longest lens which is F2.5. The 223M has a varifocal lens from 4mm to 8mm. The aperture at 4mm is F1.5. Axis does not specify the aperture at 8mm, but the aperture is likely much smaller (higher F value) than 4mm, which would reduce the light to the sensor. Reducing the aperture by one stop will reduce the lux sensitivity (increase the minimum lux number) by one stop. - It is easier to optimize the performance (sharpness in particular) of a fixed lens vs a varifocal lens. Since the Axis specs fail to include the exposure time used to measure the low light lux rating, it's difficult to compare the night performance of the two cameras on paper, but the list of issues above make the M12D a compelling design compared to the 223M. Best, Christopher PS: Kudos to Mobotix for including the exposure time in their product specifications.

Wow, that looks pretty good! Do you know the shutter speed? The car is not blurred, but it may have been driving very slow in the snow. I have an Axis 223M and although we don't know the lux value at your house vs mine, judging from this photo, I would say the M12D has much better low light capability compared to the 223M. Of course, the M12 has a sensor devoted to night, and I also think the M12D may have a much larger sensor as well. I also like the M12D form factor compared to the 223M. The 223M requires a large enclosure, while the M12D is built for outdoors. Plus, the PIR sensor is included with the M12D, and I had to add a separate PIR for the 223M. The M12D looks like a real winner. Feel free to post more information as you continue your testing. Best, Christopher