Introduction: Build Ring Light for Your Camera
I did not want to spend several hundred pounds of professional equipment, hence I was happy to find the following site:
This was simple enough for me to build, made from components that are easy to get.
You need the following:
- T10 21-LED White Light Car Angle Eye (70mm Diameter) from Dealextreme
- T10 24-LED White Light Car Angel Eye (90mm Diameter) from Dealextreme
- T10 39-LED White Light Car Angel Eye (120mm Diameter) from Dealextreme
- Big Altoids peppermints box from local supermarket
- Old laptop power supply “borrowed” from work
- 3.5 mm stereo plugs and socket, 3 each. I used a socket which has screw mount, so it is easy to fit into the box.
- 2.5 mm DC socket that fits your power supply plug
- TS7812 1A 12V fixed voltage regulator
- 9V battery clips
- Adapter ring, my Canon ESO 300D has 58mm ring
- Some cable
The Altoids box is big enough to fix two 9V batteries which give enough voltage when connected in series. The voltage regulator keeps the voltage on 12V which is required for the LED rings. In most cases I would use the ring light when mains is around hence I opted for the external power supply.
The adapter ring I used to mount the ring light on is a 58-58 mm Marco Reverse Adapter Ring that I bought from this store: http://stores.ebay.com/ADPLO. This has a nice rim where I could glue the base on.
The electronic components are either Maplin or Farnell. There is nothing special about them. The voltage regulator heats up during use, especially if the “in voltage” is high. I am using an old 19.7 V laptop power supply. Just to be on the safe side I put a small heat sink on the voltage regulator. Note that in my ring light I was using the base ring of the 3.5 mm jack for ground and the outer connector of the power supply is also ground. These terminals are connected through the metal mounting screws and the box. So if your power supply has the positive outside and the negative inside it can cause short circuit.
See the video from the build:
Step 1: LED Rings
These ring light were designed for automotive use (to create BMW like light rings I presume) hence they are running from 12 volts. The rings are 8 mm wide so you can only fit the D80 around D60, or D90 around D70. They give a very homogonous white light, not blue and not yellow either. My rings draw 100, 130 and 170 mA respectively. With all three turned on it is still less than half amp which is under the voltage regulator’s 1 A threshold.
Step 2: Assembling the Light Rings
I used the cover of a 10 pcs CD/DVD case as the base. I am using the biggest 120 mm ring which fits comfortably in the case. Cut a circle in the middle to fit the adapter ring. It depends on the type of your adapter ring, but the CD case should site on the rim of the adapter ring giving enough space to glue the two together. I used regular superglue (CA) to glue these two parts together. Cut back the side of the CD case. I was originally planning to cover the front face of the ring light, but so far it is open. Keep the side the same height as the whole assembly (adapter ring depth and LED ring depth) in case you wish to cover it with a semi transparent material to help diffusing the light. With all LEDs on, the light diffused enough. I can’t see the individual LEDs in the pictures unless shooting something highly reflective.
Using a soldering iron I removed the leads from the LED rings and soldered my own cable on. I had some 3 wire cable around, from which I used 2 wires. I left the cable around 1 m long which would be the distance between the box in my pocket and the camera in my hands. I soldered the other end of the wire to the 3.5 mm jacks. I used the bottom ring for the ground (marked as “-“ on the back of the LED ring) and the tip for the positive voltage (marked as “+“ on the back of the LED ring).
Before soldering the jacks on, I drilled small holes on the case one for each ring push the cable through the hole. I tested that the connections are working and the all 3 rings are working. This is important before gluing them on the base. After that you will not be able to access the back of the LED rings. I used two part epoxy to fix the rings to the CD case. I used tape to fix the cables to the back of the case 5 centimetres from the holes. I glued (with CA) the cables to the back of the case to fix them in place. Then I put some more epoxy over the wholes and the first few centimetres of the cable to lock them in place further.
That’s all there is to it. As I said you can think about mounting a screen on the front if you wish to diffuse the light. I might do it in the future, but I am happy the way it is at the moment.
Step 3: The Juice Box
Use a big Altoids box. There are a couple of reasons I used this. First of all I saw the same application on the original ring light page. Secondly two 9V battery fits comfortably inside and even leaves space for the sockets and the voltage regulator. Thirdly it was very easy to mount the sockets in them.
I drilled 3 holes for the 3.5 mm jack sockets on the short side and one bigger hole for the 2.5 mm DC socket on the long side under the hinge. Just push the components through from the inside and fix them with the screw. Now the electronics.
Take the two battery clips and solder them in series: solder the red wire from one for the clip to the black wire of the other clip. Now you will have 9+9 volts between the free red and black wires. Now connect the free black wire, the ground terminal of the DC socket, all 3 ground terminals of the 3.5 mm sockets (pin closest to the box in the middle in my case) and the middle terminal of the voltage regulator together (black wires on my picture). Connect the free red wire from the clip, the positive terminal of the DC socket and the left pin of the voltage regulator (letters on the regulator facing you) together. Now connect the right pin of the voltage regulator and all 3 positive pins of the 3.5 mm sockets (pin on the right in my case) together.
Note that there is roughly 2 V drop on the voltage regulator. So you need at least 14 V from your external adapter for full light. If you happen to have a 12 V adapter, you need to connect the positive DC socket terminals to the “out pin” of the voltage regulator – to bypass it.
That’s it, it should work now. Put the batteries in and connect plug the rings in. Don’t use the batteries when the external adapter is connected. Either use batteries or the external adapter. Just to repeat what I said earlier. The screws on the DC and the 3.5 mm socket are connected to one of the terminals. If these terminals are not both ground you can create a short circuit. I also put a tape around the battery clips to make sure that they don’t touch the box from the inside which again can cause short circuit if used with the external adapter.
Step 4: Results
See a few examples below. Mines are not as dramatic as on the link in the beginning of this article. But you can see that there are much less highlights and cast shadows using the ring light. The railway pictures show that nicely. You can see all the details there are no harsh shadows. Exposure is more uniform. These pictures have not been altered. White balance is as the auto white balance function determined it. I am not saying that it gives an artistic result, but it is the best for documentation purposes where too much shadow makes the image hard to interpret.
Step 5: Conclusion
These are the things that I learned while building and using this light ring. Consider them while designing your ring light.
- My Canon camera other ring which the light goes on rotates as the camera focuses. The focus motor can easily rotate the ring light but make sure that you have plenty cable around and it can rotate freely. You don’t want to burn the focus motor in your lens.
- It is not always easy to screw the ring light on the lens with all the cables around. You might consider mounting a lightweight socket on the back of the CD case. Screw the ring light on the lens without the wires and plug it in afterwards.
- You can hook all rings to the same cable. Reason I have one for each so I can unplug any of them if I don’t need so much light.
Have fun and happy shooting.