cglaeser
DIY'er-
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Everything posted by cglaeser
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Before the introduction of IP cameras, I'm guessing most manufacturers were using 1/30 and therefore did not specify the shutter speed with the minimum lux value. Now that many IP cameras support DSS with very low shutter speeds, it's become impossible to compare the lux values in a meaningful way since we can no longer assume a 1/30 shutter speed was used. While it is true the Axis does specify the shutter speed range supported by each camera, they do NOT specify the shutter speed used to measure the minimum lux value. Based on my measurements of the 223M, I believe they use the slowest supported shutter speed when reporting minimum lux value, which is very misleading. In contrast, Mobotix does report the shutter speed with each reported minimum lux value, and they often cite two lux/shutter speed combinations (one realistic shutter speed and one very slow shutter speed). Kudos to Mobitix. Axis needs to update all their data sheets to include the shutter speed with those lux values. Best, Christopher
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Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
Nope, that won't do it. 1&1 puts too many websites on each server, and no amount of persistence from a customer is going to change their website-to-server ratio business model. If you run a forum and you want to provide good performance, you have to be prepared to move to a new hosting service. Hosting services that provide good performance today may let it slide in a couple of years, so unless you can afford a dedicated server, you may have to move every few years. Either that, or suffer the poor performance when it declines. Best, Christopher -
The real problem is that few manufacturers include the shutter speed when citing a minimum lux value, and many of the new IP cameras support a shutter speed as low as 1 or 2 seconds. For example, I have an Axis 223M megapixel day/night camera. The data sheet lists a low light value of 0.2 lux. However, my testing indicates that this 0.2 lux requires a 2 second shutter speed, which is useless for anything but stationary objects. My front driveway is illuminated with a 5 lux street light, and even that is too low for the 223M using a 1/30 shutter speed. So, to answer your question, when you compare lux values, you must also compare shutter speed. Since most manufacturers fail to include the shutter speed, it's difficult to do a meaningful comparison. Best, Christopher
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Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
It must be moved to a better web hosting service. The 1&1 hosting service puts too many websites on each server. While the traffic to the CCTV forum is relatively low, it must compete with all the other websites that share the same server. Best, Christopher -
Couple of quick points: - There are some very low lux cameras, but they are relatively expensive (may cost $8,000 or more). - Manufacturers typically do not mention the shutter speed with thier low-light lux rating. To achieve those low lux numbers, they may use a 2 second shutter speed, which is useless if you want to record movement. For example, 0.1 lux at 1/60 is considerably better than 0.01 lux at 2 seconds. Best, Christopher
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Our Axis camera mobile demo system.
cglaeser replied to thewireguys's topic in IP/Megapixel Cameras and Software Solutions
Would be an extremely compelling demo if there was a way to precisely control night lighting at various lux levels (e.g. 1.0, 0.5, 0.1, 0.05, and 0.01 lux). Best, Christopher -
Parking Lot - Help me capture theifs and vandals
cglaeser replied to noreason's topic in Security Cameras
Check out the Axis 233D. It includes 35x zoom PTZ with autotracking. http://www.axis.com/products/cam_233d/index.htm Best, Christopher -
Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
Performance remains poor. I've read this book before. I know how it ends. Performance will improve when this forum is hosted with a top-rated hosting service. You can talk and talk to the current hosting service, but in the end, it won't help. I know it's not easy picking up sticks and moving to another service. Been there, done that. However, after the move, you'll say wow, why did I wait so long. Check out some of the Top 10 Web Hosting rating services and read the reviews. Best, Christopher -
Brownout? Thermal? Do you have a good power supply?
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Parking Lot - Help me capture theifs and vandals
cglaeser replied to noreason's topic in Security Cameras
What is the size of the parking lot? Is there light at night? Best, Christopher -
Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
Unfortunately, there's not much we can do about it except do as you have done and continue to report the problem to the forum moderators. As was stated above, this problem is not caused by issues on our computers. The problem is at the server. The most likely cause it too many virtual hosts being hosted on one physical server. Someone needs to contact tech support at 1&1 and request improved bandwidth. Best, Christopher -
low light or super low light IP security cameras
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
Thanks. Did you find any specs that specify the shutter speed of the 0.01 lux? I located various specs on the net, but no shutter speed. Best, Christopher -
low light or super low light IP security cameras
cglaeser posted a topic in IP/Megapixel Cameras and Software Solutions
Are there any IP cameras with a lux rating as low as 0.01 or even 0.0005 rating? Best, Christopher -
low light or super low light IP security cameras
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
Thanks, the Axis 223M has those settings as well. Here's the problem. When manufacturers publish low light specifications, they typically do not include the shutter speed required to achieve that lux value. For example, the Axis 223M specifications are 0.2 lux, BUT .... at what shutter speed? Well, my testing indicates 0.2 lux requires a shutter speed of 2 seconds. Sure wish I had known that before I purchased the camera. 2 seconds may be fine for viewing parked cars, but is pretty much useless for person identification. So, that's why I asked about the Arecont low light lux value and shutter speed. Is that 0.01 lux at 1/60, or is it 2 seconds? That's a *huge* difference in performance, and that's why 0.01 lux does not mean much without specifying the shutter speed. Best, Christopher -
Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
This forum is much too small for that to cause performance problems. Best, Christopher -
low light or super low light IP security cameras
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
Right, I added megapixel to the thread. I found a product spec on the net that indicated 0.01 lux, but the specs did not mention the shutter speed. Based on my experience with the 223M, I know how that game can be played (i.e. extremely long exposure time to achieve low lux value). Do you know the shutter speed of that 0.01 lux figure? Best, Christopher -
Slow connection to the forum
cglaeser replied to CCTV_Suppliers's topic in Questions about this site
It's probably the web server. Most hosting companies use virtual servers, where many web sites are hosted on one physical server. To save money, some hosting companies cram far too many web sites onto one server, and performance drops to practically unusable. I had this problem with AIT, and it just kept getting worse, so I reviewed a web hosting rating service and selected Hostmonster.com. So far, performance has been exceptional. Best, Christopher -
low light or super low light IP security cameras
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
The problem with the Axis data sheets is they don't specify the shutter speed used to measure the reported low light rating. Any exposure longer than about 1/25 is not really usable for a security camera, but Axis typically use exposure times much longer than that. I have the Axis 223M, which has a low lux rating of 0.2 lux in the data sheet. What they fail to mention is the lux rating is for exposure times of between 1 and 2 seconds, which is completely unusable for person identification. I have measured the low light capabilities of this camera, and a shutter speed of 1/25 is no where near 0.2 lux. So, when I see an Axis low light rating of 0.008 lux for the 223D without an associated shutter speed, it make me wonder. FWIW, Mobotix does include shutter speed with low light ratings, so their numbers are useful. Are there any low light fixed megapixel IP cameras available? Is there anything comparable to or better than the Mobotix M12 SEC Day-Night? Best, Christopher -
New Axis M1031-W just arrived
cglaeser replied to thewireguys's topic in IP/Megapixel Cameras and Software Solutions
This must be them ... http://www.axis.com/promotion/new_generation/products.htm Best, Christopher -
New Axis M1031-W just arrived
cglaeser replied to thewireguys's topic in IP/Megapixel Cameras and Software Solutions
To which camera are you referring? Best, Christopher -
New Axis M1031-W just arrived
cglaeser replied to thewireguys's topic in IP/Megapixel Cameras and Software Solutions
Slick. I especially like the form factor. Best, Christopher -
New Axis M1031-W just arrived
cglaeser replied to thewireguys's topic in IP/Megapixel Cameras and Software Solutions
Can you provide any details? Best, Christopher -
Comparison of Axis 223M and Mobotix 12M
cglaeser posted a topic in IP/Megapixel Cameras and Software Solutions
Does anyone have experience with both the Axis 223M and Mobotix 12M or is there a review on the net that compares both? In particular, how do they compare wrt low light at night? The specs of each camera list the minimum lux level, but the 223M specifications do not mention the shutter speed used to determine that lux level, so it's difficult to compare based on specifications. Best, Christopher -
Comparison of Axis 223M and Mobotix 12M
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
I use a Minolta IV, but pretty much any photo light meter will do. You can find conversion tables on the net that will convert ISO/shutter/f-stop to EV to lux. Best, Christopher -
Comparison of Axis 223M and Mobotix 12M
cglaeser replied to cglaeser's topic in IP/Megapixel Cameras and Software Solutions
Here's an image taken with the Axis 223M at dusk. http://tinyurl.com/bfy4u7 I waited as long as possible to take the dimmest light that might be usable for identification purposes. The light meter indicates ISO 400, 1/4 second, f/1.4.7 (this meter can measure fractional f stops). That corresponds to about 7 lux. The Axis is set to 1/50 shutter speed and 36 gain. IMO, 1/50 is the slowest shutter speed possible to keep motion blur under control. Setting the exposure time to anything longer (e.g. 1/25) causes too much motion blur to really be useful. I think this image is barely usable at 7 lux. At 1 or 2 lux, the image is too dark with too much noise. The Axis brochures indicates a minimum illumination of 0.2 lux, which is considerably less than 7 lux. Why the huge difference? Because they are using an exposure time on the order of 2 seconds. Here's an example of me walking very slowly when the exposure time is set to 1 second. http://tinyurl.com/b43297 Is that me, or is that the dog standing on hind legs? More important, is this really a day/night camera? Best, Christopher