Homemade starlight camera

[Tehnicni]

My idea is to put together a great starlight camera that will operate at night with minimal white LED lighting. So I need as much of your experience, especially with a lens with IR filter and a big aperture.

Personally I need a camera that will cover a square area of my front yard, so I'm targeting IMX225 board with a 4: 3 sensor, which will gave me picture almost as 2K model (960/1080) for half price of IMX291 board. 4mm lens will be just right.

Holder for CS lens
Board
Or all in one

 

[hmjgriffon]

My idea is to put together a great starlight camera that will operate at night with minimal white LED lighting. So I need as much of your experience, especially with a lens with IR filter and a big aperture.

Personally I need a camera that will cover a square area, so I'm targeting IMX225 board with a 4: 3 sensor, which will gave me picture almost as 2K model (960/1080) for half price of IMX291 board

Following.

 

[Tehnicni]

Today I got starlight module 1.3MP HD 960P Starlight Network IP camera Module Colorful Night Vision Sony IMX225 Sensor, here are the first results of comparison with TOP-308.
Lens on both camera is the same varifocal 2.8 - 12mm. On IMX225 was set to max (12mm), at TOP-308 to get same picture width. Both with IRcut filter.
Both camera was set to 15 fr/s 2048kb/s, sharpnes 0, Brightnes 70, contrast 42, GOP interval 2s.
All pictures are taken at the highest light at which there is no closing operation of the shutter or AGC, so white level is always bellow 100%.
The distance from the wall of the racks to the camera was 3.2 m, illumination: 12V LED stripe 160 cm from the wall.
3 pictures is grabed at Closed AGC (AGC = 1), all 5 pictures at Slow Shutter at None.

If you compare Top-308 at 200mA LED light with IMX225 at 20mA LED seems that the IMX225 is 10 times more sensitive than the sensor in TOP-308
IMX225 is 24% wider.
My module have heatsink on CPU, which extends beyond the module border, so you can't put it into 38 x 38mm housing.

Now I have to find a 5mm (+-1) lens with a large aperture. I already ordered 20mm IR-CUT-CS-mount, so suggestion for both types of lens (M12 and CS) is welcome

 

[Tehnicni]

Picture of the module with heatsink

 

[00Buck]

Have you seem these? http://www.ebay.com/itm/262760133657?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[Tehnicni]

Ful HD is not interesting for me, because I need 4:3 image format (front yard shape), which I can get from IMX225, so I have 960 vertical resolution.
Picture at day light with TOP380 and from IMX225
Lens on both camera is the same varifocal 2.8 - 12mm. On TOP-308 was set to min (2.8mm), at IMX225 to get same picture width.

Picture at 1W LED with TOP380 and with IMX225 at 960 line format
Neighboring house is illuminated by the moon. Between winter garden and garage is night vision 0.1W LED lamp.
On both camera Slow Shutter High (f/s decrease to aprox 2f/s) and AGC 50.

 

[Tehnicni]

Fnally got the lens and also moon is in good condition
My twitt:
Security camera in front of my house. 4mm M12 lens (decl. f1.2, measured f1.4) on #starlight IMX225 module 15+21€. 96% moon at 37° elevation Tone Martinjak on Twitter

Camera is 4m from the ground.

 

[Kawboy12R]

What's the exposure time? A good picture of your landscaping won't help the cops identify the blur walking through the yard. If that's at 1/60th of a second I'll be impressed.

 

[Tehnicni]

I know that. Slow Shutter is at High, so f/s decrease to aprox 2f/s, AGC is 55.
Any way, at night almost any lighting produce overexposed faces.

 

[Kawboy12R]

With wide-angle lenses, yes. With built-in IR, usually yes. Cheap cameras with low dynamic range, yes. Blown out faces are common but they don't have to be. Limit the scene with a narrower lens, light up the background so the camera isn't straining to see it, and have at least the bulk of the lighting separate so when a face comes close it doesn't catch most of the light and act like a reflector against the almost black background. Good, effective lighting is artistry. Ask any director. Control distance, angle, and lighting and you've got your mug shot once you've got the settings in your camera set right. Auto mode usually sucks.

I like your results, don't get me wrong. I just don't think you will get a face shot unless you can convince somebody to stand absolutely perfectly still looking at the camera without moving an inch for about two whole seconds.

 

[MakoMillenium]

At night.......Face or identity detection is a "nice to have" especially in a forensic sense after an event, so don't get me wrong. In the real world, real time detection rather than resolution is first prize as the threat can be dealt with either by deflecting it or evading it. For this identity is not as important as simple detection and identifying body language as friend or foe. Witness bababouy videos where persons are monitored while security / police are guided in for the real job of detaining and identifying on scene. In most cases video identity isn't needed.
Even in relatively small communities good resolution IR pictures very seldom lead to a solid identification unless the subject is known to the viewer and even then it's only useful as an investigation lead. Daytime high res of course is very useful but again unless the troublemaker is known to the person viewing the video/picture after the incident it's only useful for planning/defending against future events.
Police are generally not inclined to go on video evidence especially if the crime is considered 'low level' and will cop out by saying the resolution is not good enough which ends the investigation and leaves the victim thinking they are the problem and need better CCTV.
For hobby CCTV high res is great and resides in the same arena as the latest cellphone or gaming kit and is very satisfying.
For serious intruder/criminal detection low res thermal with zero chance of identity reveal beats high res anything.

 

[Tehnicni]

The last sentence I do not understand.
Blown out faces (at night) can be avoided by settings AGC to optimal value for burglar face in front of the door.

 

[MakoMillenium]

Tehnicni, IMO it's more important to know that someone is there and read the body language than it is to get a high res identifiable image (which is a nice to have) if you can get it. I'm obviously ignoring well lit scenarios.

 

[Tehnicni]

I totally agree especially because you need more than 100 times more pixel for face recognition and complex illumination system.
I must check Slow Shutter settings on body silhuete sharpness

 

[randytsuch]

Tehnicni, IMO it's more important to know that someone is there and read the body language than it is to get a high res identifiable image (which is a nice to have) if you can get it. I'm obviously ignoring well lit scenarios.

I disagree, at least in my application.
I almost never watch my camera feeds real time. If this is for personal use, I think most peopled are not watching feeds.
For me, the entire point of the system is to see who the bad guy was, if something does happen.

But, if this is for commercial use, with someone sitting in front of a bunch of monitors watching feeds, then I get your point.
But for commercial use, they will buy a camera, not build one.

 

[Tehnicni]

These lens is not 4, but 3mm, with apperture 2.8mm (my measurement), which mean f1:1.1 which is fantastic. Apperture of varifocal 2.8 - 12 at 3mm is 1.6mm.

With AGC 55 & without slow shutter picture have 2much noise.
Picture at full moon, AGC 51, Slow Shuter at Low 7f/s 720p

You can see me walking at normal speed
And with same param. only Slow Shutter at None: 10f/s 960p

10f/s is maximum for these board for 960p, for 720p max is 14f/s.

For comparrison daylight picture