Making Raspberry Pi in the NoIR - Part IV - assemble IR lights
Updated: May 24, 2020
If you don't know what this post is about, go back to Part I to find out.
There are two types of infrared (IR) light sources that I trialled for the nocturnal cameras. One good, which I detail, and one bad, where I explain why I did not use them.
The Good Lights:
The first is a kit from BrightPi. This is what I am actually using. It is a little more expensive but it comes as advertised. There are 4 x white LED lights and 8 x IR LED lights. All of this needs to be soldered.
Let's start with some basics about the kit.
It comes with the BrightPi board (PCB) which you will solder all the bits to
It has four female-female jumper cables - no need to pull these apart
There are 8 x IR LEDs - these look clear when viewed from above - see images above
There are 4 x white LEDs - these look yellow when viewed from above - see images above
All lights have a long pin (anode) and a short pin (ground) - this is important - see images above
There is a small 4-pin header connector - the pins have a bent side and a straight side
There's a bunch of plastic screws
Let's start the assembly.
Turn on soldering iron - usually around 350 degrees for non-lead solder. Make sure your work area is well-ventilated.
Check out the board. The inner circle of holes is for the IR lights, the outer corner holes for the white lights. One side of the board has little semi-circle drawings on it - this is the side that should face you. The black arrow heads indicate the side with the negative charge. The negative charge on the board needs to be paired with the shorter 'ground' pin on each light.
Insert one of the central IR lights. Remember: black arrow heads = shorter pin on light - as indicated in image below. Flip the board over so the light can rest on something while you solder the back.
Touch the end of your solder spool to the base of the board where the light pins stick out. Touch your soldering iron to the spool. You will see some smoke and a tiny droplet of liquid metal will form. Try to touch this liquid metal to the board and the light pin so that a 'seal' is formed. This seal will hold the light in place and conduct the current for power. Don't make it too big - too much metal makes the current work harder.
Repeat for remaining lights. Remember: 8 x IR (clear), 4 x white (yellow).
Trim the excess light pin wire at the back of the board.
Now, insert the 4-pin header connector. The bent ends should go into the board so they poke up toward the light heads (see figure). The longer ends will point directly out from the base of the board so you can attach the jumper cables. Solder the 4-pin connector in place.
Attach the jumper cables. There is a system to this - don't just put them on any old way. Refer to the figures below to match the right colour cable with the right GPIO pins on the Pi board.
If you have the Pi camera mounts, you can use two of the black screws to attach the camera to the plastic mount. Use the two lower holes and DO NOT over-tighten as you may damage the camera components. I added a small strip of mounting foam to the camera mount so that the camera was balanced. Without the foam, the chip on the camera that you could squish tends to position the camera at an angle. Then use two of the plastic screws that come with the BrightPi to attach to the camera and the mount.
Note: the natural orientation of the Pi camera is with the ribbon at the bottom. This means that if the ribbon is at the top, the image will be upside down. You can fix still images in a batch job using > raspistill -vf -o *.jpg
Here are some before and after images showing the difference that the small piece of mounting foam can make to the angle of the camera. On the left, you can see how much of an angle is created by the camera chip. This means your camera doesn't point straight very well. The addition of the foam (on the right) helps a lot.
Hooray!! You made a BrightPi light system. You will need to install some scripts to make these run, but let's get the OS tested and motion detection software installed first.
The Bad Lights:
The second is a kit that I gave up on. It is a kit containing 2 x IR lights that came from Tinkersphere. These IR lights are LEDs to reduce power use and they have diodes that automatically detect when it is 'night time'.
Above is what the lights would like if you could just power them through the camera as advertised. However, they are falsely advertised ! The ad claims that they will just screw onto the V2 NoIR camera and be powered. This is incorrect. The screw holes are plastic so they cannot carry a current to power the lights. This means you will have to solder some bits and pieces.
This is not the reason I gave up on them. If you solder the male section of a male-female jumper cable to the metal screw hole of the IR light you can achieve power. The female section then slides onto the 5V and ground pins on the GPIO board (see image below - pins 4 and 6).
The reason I gave up on them is because they get ridiculously hot. So hot you would need another heat sink to stop them overheating. Another reason is that the solder points are weak which means the connection breaks or you have to wire them so the screw holes become useless for connecting the lights to the camera. For these reasons, I provide no further instructions.