Portable LED Ringlight for Photography
by Nuonaton in Circuits > Cameras
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Portable LED Ringlight for Photography
A friend of mine asked "Could I build that" And there is only one reply to building something new. The LED ringlight was born. I don't quite have the right tools for this build, but I will let you in on a little secret: Sometimes it's not about having the right tools, But knowing how to use the wrong tools right.
The design allows a camera to be mounted in roughly the center of the ring of LED strip lights that sit behind a fresnel lense and diffuser. Running on 12 volts allows the flexibility of using a mains power adapter OR a 12V battery, OR a car adapter for traveling. Want to build one? Get ready to solder!
Please vote for my project in the contests!
I Neeeeed Stuff!
Not much actually, though you may need some different tools than I used... .
LED Strips (Cheap on Amazon!)
A razor knife for stripping the "waterproof" coating from the lights,
Wire strippers for your contact wires and cutting the strips to size
14 gauge wire for the contact rings (I used 0 gauge. 10/10 do NOT recommend!)
a good soldering iron. (My Hakko 888D is GREAT!)
A router for cutting the aluminum (A bandsaw would be better but I use what I have)
1/8 inch thick Aluminum sheet (Found mine on the road after a scrap truck swerved to avoid my mailbox as it jumped out in front of him... You know how that happens.) My ring is approximately 18 inches in diameter with a 9 inch center opening and a 3 inch "tongue" in the center for camera mounting.
Double sided carpet seam tape. (You may love it... you may hate it. Keep some at hand at all times and things will stay stuck.) Find it at home improvement stores!
Eggcrate Found around the fluorescent fixtures at Lowes and Home Depot
Fluorescent diffusion material (I don't know what it's called but it is acrylic with pyramids on one side, about 1/8 inch thick) Found with the eggcrate
A scroll saw or band saw to cut the eggcrate and diffusion material
lots of wire. Thermostat wire works pretty well, I used some hookup wire that I got at a garage sale for $0.25
Flux for all copper to copper attachments
solder
Silicone sealant to help insulate any possible shorts. It's going to happen. Trust me.
Space to work and a decent vise for bending and holding the ring as you work on it.
1/2 inch tubing, I used air hose
8x 1/4 - 20 bolts with matching nuts and washers
drill and drill bits
wire
heatshrink
buck converter
That's a lot of stuff.... Not really, but it seems like it when you write it out!
Layout and Cutting
The first thing you need to do is layout your circles. Find the center of your aluminum and mark it well.
Layout a 3 inch circle, a 9 inch circle, and an 18 inch circle.
Cut the 3 inch circle PARTIALLY OUT as in the photo. DON'T bend it yet, but this will be your "tongue"
cut the 18 inch circle so the outside is smooth.
Cut the 9 inch circle partially so it matches the 3 inch circle, and remove the majority.
Mine is shown after the "Tongue" is bent. If you bend it last, this is an easy operation even using the router.
Now..... How did I do this?
I mounted a router upside down on my lathe workbench (It's the heaviest, most stable work area for now) and drilled a 1/8 inch hole at 1.575 inches, 4.575 inches, and 9.125 inches then drilled a 1/8 inch hole in the center of the aluminum sheet. Dropping a 1/8 inch pin in one hole at a time and running the router while rotating the disk INTO the cutting edge of a 1/4 inch end mill in the router resulted in an excellent finish and accurate circles. Hindsight what it is, I would use at least a 3/8 inch end mill and increase size to suit the bit I chose accordingly. Hard to imagine? Let me know and I will make a YouTube video showing the process.
Now, bend the tongue over like in the photo.
Experimenting With LED Layout and Finalizing the Design
Layout is important. The better we plan, the less we fail.
You can see I tried several designs before choosing the final rendition.. Once I had settled on a layout, I stuck the double sided carpet tape to the aluminum (AFTER CLEANING IT WELL WITH ACETONE!) and carefully stuck my LED strips down (STRIP THE ENDS FIRST!!!!)
Soldering and Testing and Soldering and Testing.... .
If I said it wouldn't take long.. I'd be lying.
Anyway, It won't take you long to solder all these lights. assuming you place 66 lights as I did, there's only 264 contact points to solder. No biggie.
Since soldering is tedious, I took few photos, but I have some tips.
1:Layout each strip with + facing the same direction. It prevents confusion later.
2: Solder the heavier gauge wire side first. Just trust me on this one. It will save you time and temper.
3: Flux EVERY contact point.
4: test often. A short after hours of soldering would be disastrous!
5: Good music or an audio book. 3 men in a bout By Jerome K. Jerome and Narrated By Hugh Laurie will make the time fly!
Now, when you've soldered each point, solder a connection lead to each ring and run to the center tongue. drill a hole in the connecting bit and run your leads through.
Diffusion
Staring into bare LEDs is bad at the best of times. There are 396 to look at here. Diffusion is key.You need 3 layers to pull this off.
Eggcrate, Cut the outside diameter 1/2 inch smaller than your ringlight diameter, and the inner diameter the same size.
A fresnel lens. Easily pulled from projector style TV's. Cut each circle the same as your ringlight.
Fluorescent diffusion acrylic, Cut the same as the fresnel lens.
excepting the eggcrate, these can be cut the same way we cut the aluminum.
The eggcrate will have to be cut on a scrollsaw or bandsaw.
I wish I had more photos of this, but if there are any questions I will answer them as best I can.
You'll need to drill several holes around the outside of the ringlight and diffusion assembly About 1/2 inch in, to hold the diffusion assembly in place. 8 will do it, after you've drilled your holes , wrap your tubing around the eggcrate and tape it in place (Blue tape works well) and run a drill bit through all the layers again (Be careful of the LEDs!) and push your 1/4 inch bolts through (With washers on both sides) and HAND TIGHTEN the nuts. Snugged up by hand should be good. Using a wrench will crack the acrylic. Let my mistake be your teacher.
Custom Electronics Cover
Alternatively you can buy premade covers, but where's the fun in that?
Cords and Switch
your output power supplies should have the same ends, I chose an old laptop charger (18-20v) and a car charger end. Give yourself at least 6 feet of cord on each.
Fixed Power!
solder your input to the buck converter, then your converter to the switch and negative.
Adjust the potentiometer to output 12.3 volts. set this aside.
Prepare a small heatsink for the converter. I don't know where this one came from. but after you've drilled the holes smear on some thermal grease and drill matching holes in your plastic cover, run a zip tie through the holes and set your converter between the heatsink and cover and pull as tight as you can to snug the heatsink up to the grease.
Some carpet tape or foam tape behind the converter add a sense of security before you ziptie it into place.
If like me, you're nervous about heat in spite of the heatsink; You can take this time to wire in a fan. I included a photo, but no how-to. I added this to appease my paranoia not because I think it absolutely necessary.
If you're going along with his Instructable, Please check the notes on the photos! They highlight things I feel need more explanation.
Wrapping Up and Testing
A hole drilled about an inch from the back of the tongue is where the camera quick connect holds the camera in place and mounts to the tripod.
Failures and More Test Photos
I wanted a 9 volt battery to serve as a backup power source in case you needed it to be even more portable. In hindsight, an 18v tool battery would serve better. A 9 volt through a booster is only powerful enough for about 60% power which is barely enough to do anything. good idea... But my lack of experience here means it's poorly implemented.