Build A Camera

Parts and Tools needed

Annotated Parts List

Click on the image to the right to see a larger version with the parts labelled

1. IMX291 sensor board
2. Lens with the lens holder - 4mm, 6mm are M16 mount as pictured, while other lenses might be CS which have a different holder
3. 2x M2 screws
4. Camera housing
5. Small cable gland
6. Large cable gland
7. Camera PoE cable (sometimes called a network cable by the sellers)
8. Camera board holder
9. Holder metal plate
10. 3x M2 screws, 12 mm long
11. 1x M3-.50 screws, 6mm long
12. Metal plate screws supplied with the housing
13. Transparent weatherproof silicone
14. Housing mounting bracket
15. Waterproof ethernet cable protector
16. Pair of PoE adapters (not shown) or a PoE injector (not shown), to supply 12v to the camera.
17. 12V power supply for the camera (not shown)

Some cameras come with a slightly different cable with a separate 12v socket for power input as shown here. If you have this cable you will need a pair of PoE adapters. If your camera has a single cable as shown in the main picture, you will need a PoE injector or single adapter.

You will also need small wire cutters and various size screwdrivers, plus a drill and suitable screws to attach the bracket to a wall.

To test and focus the camera you will need VLC. This software is preinstalled on the Pi but is also available for Mac, Windows or Linux from here.

Notes on Purchasing

• The Camera, lens and camera PoE cable should be bought together to ensure they're compatible.
• The camera housing, board holder, plate, cable glands and mounting bracket normally come together too, but you may need to ask the seller to include the camera board holder and bracket.

• The camera and housing can be bought from AliExpress. There may be other sources but we have yet to find any reliable ones.

• Other items can be found in most hardware stores or your favorite online retailer.

Assembly

[Note: there's a longer version of the camera assembly section of this page available on Google Docs. Please refer to this if you need more information.

Preparing the Lens Punching out the filter Start by removing protective covers from the sensor and lens. Take care not to touch the sensor after this! The cameras come with an IR Block filter in the lens holder. We don't want this, so unscrew the lens from the holder and using a screwdriver, carefully punch out the filter from the front as shown in the image on the right. If it shatters, make sure there are no shards left. Next look on the underside of the lens holder where you will see two plastic nubbins. These get in the way, so using the wire cutters snip them off. Then screw the lens back into the lens holder.

Attaching the Lens to the Camera Attaching the Lens Carefully unclip the circuit board from the plastic holder but do not detach the ribbon cable. Using the supplied screws, attach the lens to the sensor. Replace the circuit board in the plastic holder.

Preparing the Camera Housing Glands in Place Fit the small cable gland to the housing and pass the loose ends of the Camera PoE cable up through, but don't tighten it up yet. Remember to slip the cap over the cable first! Fit the large cable gland in the other opening, and push a piece of plastic packing foam into it. Don't seal it up completely though this is to keep insects from getting in, but allow moisture out.

Attaching the Camera Camera In Mount Connect the metal camera holder to the metal plate using one 6mm M3 screw. Note the orientation of the plate as shown in the photo. Using three 12 mm M2 screws, connect the camera board to the metal holder passing the lens through the square hole from the back. Note that the writing on the camera board must be UPSIDE DOWN to get the correct orientation of the camera. In this orientation, the sockets for power and networking will be at the bottom of the rear of the camera board. Finally, remove the plastic cap on the lens. See image for the proper camera board orientation, so the video is not sideways or upside down.

Installing the Camera in the Housing Camera In Housing Remove the plastic plate from inside the housing and discard it. Fit the camera on its metal plate into the housing, as close to the front glass as you can get it without actually touching. A few millimetres away should be good. Looking at the camera from the rear, attach the largest connector (often with blue/green wires) to the right hand socket. Attach the power connector to the left hand socket. This connector has several pins but only two are connected (red/black). The third connector (two pins, red/black) is for a powered lens and is not used so tape it back out of the way. Once you've secured the camera in position, you can tighten up the cable glands.

Testing and Focusing At this point, your camera must be tested and focused. There's no point sealing up the housing and screwing it to the wall if its not working or isn't focused ! Testing the Camera If your camera came with a single PoE cable, connect this to a netork cable and plug the other end of the network cable into your PoE injector and supply power to the injector. if your camera came with a cable with separate network and power sockets, plug the "output" PoE adapter into the camera cable and plug a network cable into the PoE adapter, then connect the other end of the network cable into the other PoE adapter and attach the adapter into a spare socket on your home router and connect the camera power supply to the power socket on the adapter. The Camera PoE cable lights should come on, indicating traffic is flowing. After a few seconds, it should steady down to irregular flashing. If you don't see flashing lights then check the cable connections to make sure everything is plugged in properly. Find its IP Address The camera should now appear as a device on your network and to test it properly you will need to find its IP Address. Some routers will show you a list of connected devices, from which you should be able to identify the camera as a device called "LocalHost". Make a note of this address as you will need it later as well as now. If your router doesn't have this facility, there are many free pieces of software such as Zenmap that can scan your network for IP addresses. Checking for Obstructions Once you have the IP Address, open VLC on your Pi, Mac or Windows machine, and from the "Media" menu, select "Open Network Stream". Enter the following into the address box, replacing 1.2.3.4 with the address you got earlier rtsp://1.2.3.4:554/user=admin&password=&channel=1&stream=0.sdp After a second or two, you should get a view through the camera. If nothing comes up, check you have got the right IP address, and that the cables are secure. You can now double-check that you installed the camera the right way up... You should also close the housing case up and check if it can be seen obstructing the view anywhere. Move the camera around in the housing to minimise the obstructions, and if necessary bend the metal bracket forward a little to angle the camera down a bit. However, dont worry if you can't eliminate all obstructions. Later on you will create a software mask to prevent these areas causing false detections. Focusing the Camera There's a whole separate section of the Wiki on focusing, but here's the short version !! connect the camera to your network as above. Open VLC. Aim the camera at something at around 30-50 metres away. Screw the lens in and out slowly to get best focus. Note that there's a short lag due to the network, so you should wait a second or two after each adjustment to allow the change to be reflected in VLC.

Final Steps Sealing the Housing Sealing the Housing Depending on your climate, its usually advisable to seal up the camera housing against rain and snow. From the outside, carefully go round the edge of the glass with silicone sealant. Also squirt sealant into any screw holes visible on the front of the camera housing, where it will be most exposed to rain. But DONT seal up the hinged door because you will occasionally need to maintain the camera, and you don't want to have to prise it open with a chisel!

Mounting Outside Mount the camera somewhere with a good view of the sky and without too many 'terrestrial' obstructions such as trees, hills and buildings. Take special care to angle well away from security lights. These lights emit infrared and without the IR Block filter, the IMX cameras are extremely sensitive to this. When locating the camera, bear in mind that you will need to be able to get to the camera to maintain it. The cameras do not need to be high up as long as they have a good view of the sky. Mine are at eye-level on my observatory shed. As before, don't worry if its not practical to eliminate all obstructions as you can mask off any that can't be avoided. Aiming the Camera The cameras have a field of about 40-45 degrees vertically and 90 degrees horizontally so angle the camera upwards at between 35-45 degrees. This should maximise meteor detection. If you can arrange so that the camera view overlaps with other RMS users, thats even better. Check with the network to get an idea of a good direction

Thats it!

Once the camera is installed, connect up the PoE adapter, attach a long network cable and run it to wherever you are going to keep the Raspberry Pi. Remember to ask permission before drilling holes in the walls... :)