Thursday, November 15, 2007

Ring Flash Week: Building the HD Ring Flash

I just didn't have the heart to force-feed you another donut. Even Krispy Kremes get old after three days in a row. Logo or not...
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So, here's the main structural component of the ring flash. A 16" concrete form tube. ($10.67 at Home Depot.)

This stuff is so useful for DIY goodies. I have seen giant Dobsonian telescopes made out of this. And some killer speakers, too. (No standing waves in a cylindrical design.)

I made this two days after Halloween, if you couldn't tell. More after the jump.
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The height of your device will be determined by the length of your lens and body, including shade. Since mine was a tele, I gave the PVC tube a couple of extra inches as a auxiliary shade, so to speak.

You could make this using a wide lens. But the longer it is, the more room for the flash light to disperse inside. And thus, the more even the light on the front diffuser.

I traced a line around the cardboard tube and cut it easily with a jigsaw. I never once made a measurement in the whole process. Just eyeballed, drew the line and cut. As a guy, I am rather proud of that. And it is no loss on your end, as your dimensions will be determined by the camera and lens combo you choose to design it around.

I cheated it a couple of inches on each end (extra PVC for shade and a little extra cardboard tube at the back.) I wanted decent depth for good internal flash throw. Worked out fine.

I traced the tube and the PVC (also cut to length with a jigsaw) to create the donut/washer shape for my front Plexi diffuser. I screwed up the cutting with a jigsaw, so mine had cracks (none fatal) that I had to shore up with clear packing tape. Before taping, I also sanded it on both sides to frost it. (It was not enough, as we saw yesterday, so I ended up with an addition sheet of paper inside for more diffusion.)

This shot shows how the tube and hand-bent aluminum plate brackets mount together. It is important to allow for the bolts in the PVC when checking to see if it will be thick enough for your chosen lens.

If you look at the large version, it should be easy to see how the pieces go together. The camera mounting plate is sandwiched between the PVC and one of the brackets.

You can see the "L" brackets that hold the Plexi to the cardboard tube and PVC here, too. That cardboard tube is tough. May as well be wood.

The bracket assembly bolts to the cardboard concrete form tube, making for a very solid final unit. It went together more easily than I expected.

I think the key is transferring the correct "inner tube" to "outer tube" distance for your aluminum brackets. Get that right, and you are pretty much home free.

Here is the whole thing, put together. The flashes ball-bungee to via two sets of two holes on each side. You'll need a strap, too. Put the strap holes at about 90 degrees apart and it'll ride better on your shoulder. You'll still look like a geek, tho.

You can see the paper disc inside at the bottom here, too.

I used foil-backed tape on the outside of the PVC tube all the way around. This got the light to bouncing around on the inside. I put foil-backed tape pretty much everywhere but near the flashes on the outside. Flashes are fired at the widest setting (W/A diffusers in place) and provide very even -- and strong -- light when all is said and done.

Here is a shot from the front. The light is broad, round and plenty even. I can easily work at modest portrait ranges outdoors in broad daylight, which is great.
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It is a little clunky, but hand-holdable nonetheless. Next improvements will be:

• Tripod mounts along both axes -- vertical and horizontal camera orientations.

• Spray paint it flat black, then acrylic to protect it.

• Rounded cap nuts on the protruding (1/4x20) bolts.

• Drop some money on a soft drum case to be able to take it on the road (airlines.)


Here's a photo of the business end, shot by Jeremy Reitman at the Patasco Meetup. I'll be the first to admit that this is a little, uh, gung-ho, compared to some of the earlier designs. But this thing rocks on the output and the even light, so I am one happy camper.

Oughtta have some pretty nice guns by summer if I use it enough, too...
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NEXT: Test Driving the DIY HD Ring Flash




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44 Comments:

Blogger Richard Walker said...

So the camera resides inside the tube? Do your arms not hit the sides of the tube when in use? Is the reason for this to keep the lens from vignetting?

November 15, 2007 9:14 AM  
Anonymous Anonymous said...

That thing is huge!

Might get gang-tackled by homeland security if you wander too close to DC.

November 15, 2007 9:15 AM  
Anonymous Anonymous said...

How are the flashes triggered? Are rf-triggers required or is it enough to just use the camera's master-trigger (via flash)?

November 15, 2007 9:33 AM  
Anonymous Brett Carlsen said...

The three questions that arise for me, is why the notch in the pvc tube? just for grip or does it serve another purpose? You mentioned that you wanted to do ttl, how can this be achieved accurately with the strobes pointing forward but sensors pointing inwards? Lastly what method did you use to connect the strobes to the camera (main reason for that question is because you said you could do ttl)
love to finally see a nicely designed ring flash though

November 15, 2007 9:38 AM  
Blogger Nicholaus Haskins said...

I was waiting to buy a ring light...I am soooo going to build this!

November 15, 2007 9:41 AM  
Blogger easymovet said...

hmm, the size of the diffuser makes this look more like a soft box than a ring light, i'm sure it will have awesome effect though. It looks rather like those alien bees moon units. Cool design, i will make one for sure. Not as flexible or portable as my design but i'm sure yours is about 14% more efficient since the lights don't have to bounce of any thing (mylar is only like 93% reflective in my unit).

Can't wait to see your pictures (and possible arrest stories) with that thing.

November 15, 2007 9:53 AM  
Blogger Jeremy said...

In use here:


Thanks for the photo cred, David.

November 15, 2007 10:01 AM  
Blogger Baile said...

Ummm, how much does this thing WEIGH? How much extra time am I going to need in the gym, training to use it? :-)

There is a bunch of truly creative thinking in this project. Well done!

Bill

November 15, 2007 10:15 AM  
Anonymous Anonymous said...

I'm sorry, the quality of posting on this site have gone way down. I'd pay $400 to not have to carry this thing around.

tw0phat

November 15, 2007 10:31 AM  
Anonymous Madelien said...

Wait... did you say concrete? :o

November 15, 2007 10:40 AM  
Anonymous Eric said...

@ tw0phat: Speak for yourself. I think finding a D-I-Y project to save me $350 is awesome.

November 15, 2007 10:44 AM  
Anonymous Aaron said...

Could you cut the length in half by turning the flashes around and bouncing into reflectors? Here is a sketch.

November 15, 2007 11:09 AM  
Blogger Will Foster said...

Wow, that thing is definitely a "man made" ring flash! Reminds me of something Tim "The Tool Man" Taylor would build. MORE POWER! HO HO HO!

November 15, 2007 11:20 AM  
Anonymous Jeremy Center said...

guess i got ahead myself yesterday. thanks for the pics. I bet that thing would double as a cantenna. but i wouldn't want to try to get it past TSA:)

November 15, 2007 11:48 AM  
Anonymous BoxCarPhoto said...

how much light is wasted, bouncing backwards out of the flash, right back into your face, i wonder?

could the back of this be sealed up, and line it with silver tape?

November 15, 2007 11:57 AM  
Blogger Jürgen said...

This is impressive and finally my exercise routine in the gym makes sense.
So first step, hit the gym and then start building.
I curious to see picture results.
David, how do you trigger the stroves, working with the old faithful remote triggers?

November 15, 2007 1:25 PM  
Blogger scubajunkie said...

I have to admire the creativity. I didn't realize how big it would be. I'm thinking you could put a handle on it, and make some foam inserts and put a door on the back and it would double as a camera case.

So again I ask, has anyone tried making a ring flash out of disposable camera flashes?

November 15, 2007 1:30 PM  
Anonymous dan culberson said...

I'm sure there's an answer already waiting in moderation, but for Brett Carlsen, the TTL flash is "through the lens". There is no sensor measuring the light on the flash itself--that's how older "automatic" flashes worked. The camera is handling the exposure measurements in this case.

November 15, 2007 1:32 PM  
Blogger peted301 said...

just a tip on cutting the center circle out for the tube. Use a hole saw drill bit. they come in tons of diameters.

just a thought. lexan is also less pron to crack than straight plexi. comes at a cost however.

pete

November 15, 2007 1:34 PM  
Anonymous Eddie said...

Are you serious?? Who's gonna carry this thing... Godzilla??

November 15, 2007 1:40 PM  
Anonymous Doug said...

People - don't lose sight of the goal here. Is it functional? Yup. Look cool? Not a chance in hell. Does it matter? For some, not others. It's a little bit of ingenuity, a little bit of, "you get what you pay for." What I'm saying is, don't be fooled by the looks of it, if it gets the job done, it gets the job done, period.

November 15, 2007 2:08 PM  
Blogger scubajunkie said...

@jurgen (sorry about the missing uhmlout) - The way he has it mounted with both the strobes and the camera inside the outer cylindar, he could fire it using Nikon's wireless CLS. In fact, he could even play around with varying the strobe output from one side to the other from the camera.

November 15, 2007 2:26 PM  
Blogger scubajunkie said...

I, for one, want to see some pictures that were taken with this thing, both macro and portraits. That would be the true measure of "success".

November 15, 2007 2:27 PM  
Blogger chadw said...

@scubajunkie:

Here's a page that shows how someone made a "paparazzi" costume using disposable camera flashes. The same principle could be used to create a small ring circuit of disposable camera flashes to be triggered via a single pc sync.

http://www.cockeyed.com/incredible/paparazzi/paparazzi.html

Take about 4 flashes, put them in a ring shaped reflector (cake pan?) with 4 AAs on the back and a PC sync. Throw a diffuser on the front.

November 15, 2007 3:39 PM  
Blogger Will Kronk said...

I believe David said he was firing them as optical slaves via the camera's popup. I asked him about that one. I would also think that that's why the PVC pipe is slightly notched.

November 15, 2007 4:09 PM  
Anonymous Anonymous said...

It's "hole", not "whole".

I can't wait to see the photos from this. Finally a ringlight design with lots of power and even light.

November 15, 2007 5:14 PM  
Anonymous LBC said...

I guess a smallish translucent plastic bucket could sub as the body/front diffuser just as well. cut a hole for the lens, make a mount for the camera and a few more holes for the strobes.

Great concept David!

November 15, 2007 5:38 PM  
Anonymous reg said...

I want to see the photo of Dave actually shooting with it!!! That would be the ultimate strobist symbol:- a head made of light!

November 15, 2007 6:27 PM  
Blogger David said...

Yikes" Holes it is. Did I do that?? That'll teach me to write after midnite...

November 15, 2007 6:45 PM  
Blogger Jason V said...

So, the point here is that he "made a functional ring flash", and I like the Diffused look.

For the Skeptics: Let's see YOUR ring flash and pics. :P

Thanks to the inspiration... I think I'll try to figure out how to make one like this, but I'll have to use 1 flash, and make it under 12 inches and a little lighter... Hmmm... provided time is there.

November 15, 2007 7:11 PM  
Blogger bmthomas said...

Here is another shot of it in use.

November 15, 2007 11:57 PM  
Blogger Abe said...

I'm just thinking, imagine having 4 strobes in that tube?!?

November 16, 2007 12:17 AM  
Blogger Daron said...

DH -- I'd mount this on a monopod. I use one for my 'bowl around a studio strobe reflector' ring flash and it saves my arm, I couldn't imagine using this thing without it!

November 16, 2007 2:07 AM  
Blogger theblognik said...

Cool pumpkin cannon, David!

November 16, 2007 4:36 AM  
Blogger theblognik said...

Okay, just been to Flickr and found the pumpkin gun gags already exhausted. Timing - the secret of comedy, eh?

November 16, 2007 4:42 AM  
Anonymous Anonymous said...

I thought standing waves were good for bass. :shrug:.

November 16, 2007 9:18 AM  
Blogger Bill said...

Here is a place that sells 12" aluminum tubing... paint it black and add the Nikon sticker and you're ready for market!

http://www.parallaxinstruments.com/tube.htm

November 16, 2007 4:54 PM  
Blogger chadw said...

Just in case people have missed it, a member of the strobist pool has created a prototype ringflash using disposable camera flashes:

http://www.flickr.com/photos/phased/2037587636/

It looks very promising.

November 17, 2007 3:26 PM  
Anonymous Anonymous said...

OMYGOD
You convinced me to by an AB800
Paul

November 17, 2007 8:00 PM  
Blogger David B said...

3M reflective tape might work better for a liner- it comes in ~8" rolls if you can find a vender. I used to put it on the sides of emergency vehicals, but neglected to bring a roll with me when I left that job.

November 18, 2007 12:04 PM  
Blogger Dave said...

I'm going to try building a lighter version of this, by using flashes in their normal L-shaped configuration (to reduce overall depth, building the 16" ring from sheet aluminum (riveted), and using a soup can for the inner ring. I'm thinking of using polycarbonate for the front "glass", though I might try using the plastic diffuser from a fluorescent light panel if I can figure out how to cut it without breaking it. Hopefully I'll be done next week with < $50 in parts from McMaster-Carr.

November 18, 2007 11:13 PM  
Blogger David B said...

If you don't need structural strength in your front diffuser, you might want to take a look at theatrical gels- there are diffusers available from Rosco, etc, that would be easier to deal with and lighter then polycarb or plexiglass.

November 19, 2007 11:50 AM  
Anonymous Anonymous said...

Yeah and you don't look like a tool using it.

February 06, 2008 3:36 PM  
Anonymous David Jackson said...

David,

Below is a simple DIY ring light tutorial from my blog. Feel free to check it out and post it to your blog!

http://www.davidejackson.com/blog/?p=163

Cheers,
~dave jackson

January 19, 2009 7:15 PM  

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