Home Security Camera
- Thread starter lakngulf
- Start date
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speedbump
Silver Member
Tell us more about this camera. I'm interested in something that can see 100' at night.
dickfoster
Elite Member
That's likely done with software. If it's a color camera then there is a better than 90% chance that it has an IR filter over the image sensor. Silicon image sensors are naturally sensitive down into the near IR end of the spectrum and that NIR causes color crosstalk and is why they put either a NIR absorption or NIR reflective filter between the lens and sensor to eliminate NIR before it can get into the image sensor. A pure B&W camera will not have this filter so will yield superior sensitivity in low light conditions over the very same sensor with one. Color is pretty but you don't really need it in a security application.
dickfoster
Elite Member
No doubt it has NIR LEDs supplying suplimental lighting at night. You can't see it because it's below the human spectral response curve but silicon image sensors can.
speedbump
Silver Member
Are you saying that B&W camera's would be likely to get that kind of night range simply because they are not color with this filter?
kcflhrc
Veteran Member
This is the system I bought. I got it on sale for under $200
Q-SEE 8-Channel 96H 1TB Surveillance System with (4) 9TVL Camera, 1 Night Vision-QT598-4V6-1 - The Home Depot
dickfoster
Elite Member
It depends on illumination. Silicon sensors are not true infrared cameras, just near IR. What I am saying given equal illumination and the same sensor the unfiltered camera with have superior sensitivity therefore range.
Trust me you can take my word for it, I worked for several years in the tech end for one of the largest if not the largest CMOS image sensor/camera chip makers in the world, OmniVision Technologies. I was in on the startup in fact. One of my duties was to aid electrical design engineers in designing cameras for all sorts of things, security being among them. You could even say that I'm an expert in the field although I'm retired and a full time goof off now.
speedbump
Silver Member
I don't suppose we will be seeing that deal again any time soon.
Can you even buy black and white cameras anymore?
kcflhrc
Veteran Member
It was back in late October when Home Depot had it on sale. I'm happy with it and for the money it was a steal.
dickfoster
Elite Member
Of course you can. All they have to do is leave the IR filter out and turn the color processing off. Most image sensors today, at least the CMOS stuff, has full on board image processing but it can be controlled in a lot of ways including having a B&W mode either through a serial control bus or pin programming for the common stuff and usually color or B&W mode is one of them. Here's one. It's an IP or ethernet camera with IR illumination LEDs and it's 3 megapixel High Definition camera so has useable definition. You could add more illumination to extend the range even further. You could probably find someone who will take the filter out and permanently set it to B&W mode.
Here's one that has high dynamic range too. About 115 db I think although it's not in the specs.
Indoor/Outdoor SUPER HD 4MP Network IP Infrared Bullet Camera with Smart Detection (See Up to 100 Foot in COMPLETE DARKNESS),Infrared Bullet Security Cameras, - CCTVSecurityPros.com
High dynamic range simply means it can cover scenes with dark areas and areas in bright sunlight at the same time. It has more dynamic range than your eyes do so you lose nothing. With 4 mega pixels, it's high def too. It uses an Omnivision CMOS image sensor.
Sometimes dynamic range is more important than sensitivity because you can always add illumination for the dark but you can do nothing about scenes that have a higher dynamic range than the sensor can accommodate. I got the company to develop high dynamic range sensors in order to deal with the automotive market and they found it to be a big hit in security market too.
