DIY Ring Flash for the pop-up flash

After seeing many different DIY ring flashes in Strobist, I decided to do something similar myself. The only problem was, my external flash is still in the mail... So I needed to use the pop-up flash, which I do have. Actually I think it's a very good choice, because the brightest part of the flash will be on top of the flash, which makes the darkest part of the shadow below the object, not on top of it. Using the pop-up flash limits the use of the ring flash to be used only on-camera.

The ring flash will be made out of cardboard, aluminum foil and paper. You also need some tape, scissors and a glue stick. So, no expensive tupperware needed!

If you want to use some plastic in the front plate of the ring flash, it will make the design more durable and it's easier to do. I didn't have any good plastic, so I first used a cardboard template, and then replaced it with some translucent paper.

The first picture is the front plate, that will be transparent. You can cut this out of (corrugated) cardboard and replace it later, or you can cut this from translucent plastic.

This picture is the back plate of the ring. First draw the three rings and then cut along the red lines. Also draw a vertical middle line on the back plate. You'll need it later.

You also need some cardboard to connect the plates together. I used a 65mm wide strip of (non-corrugated) pizza box with additional 20mm on both sides for easier taping. The strip should be long enough to reach around half of the outer rim. (The top part of the ring in the picture below.) You also need a strip with same width to fit in the hole in the middle.

If you are using a plastic front plate, you probably should use the glue stick to glue the foil on the insides of the ring parts at this stage. Next you connect the parts together, either with glue or tape. I used packing tape.

 

Then you need a pair of extra hands or you are in trouble... You need to have a piece of cardboard that is big enough to go around the uncovered edge of your ring flash. Place it so that the edges of both front and the back plates touch the soon-to-be cardboard wall. Then have someone draw a line on the cardboard, so you know where to cut.

Cut the cardboard about 20mm too wide again, to make it easier to glue/tape. You should have a piece like this (never mind the black lines on the bottom):

Then you attach it to the ring flash and trim away the excess cardboard. Then you attach the back side.

You need also a snoot, that will direct the light from your pop-up flash to your ring flash. I used a cardboard piece like this, but then I needed to extend the part in the bottom center another 20mm. That was because some of the light went straight through the system, not bouncing around inside the flash first. Before you glue it together, you should use your glue stick and aluminum foil to make the inside surface reflective.

The resulting snoot should be something like in the picture below. (It's upside down in the picture.) The end in the right goes around your camera pop-up flash, and the end in the left reflects the direction of the light downwards.

Then you should cut a hole in the back of your ring flash that is on the right place and is the right size. You should be able to do it by putting the ring flash on your camera, and trying to figure it out in there. You can also use the middle line you drew earlier, to place it.

Next you cut off the cardboard front plate of the ring flash. If you used the plastic one, and you have foil inside already, you don't need to cut anything off.

However, if you are doing it like me, you should start gluing the foil inside. Best way to do it is (perhaps) taking a piece of foil (about 10cm x 15cm), using the glue stick to put the glue on it, and then gluing it on the inside. Then you can already do some testing!

The light seems pretty evenly distributed. However, shooting at the wall does not give that even pattern.

Time to diffuse the light by putting some greaseproof paper (That is "voipaperi" for the Finnish readers) over it.

 

Now the diffused pattern looks a lot smoother.

That's me. Picture was shot in darkness with only the ring flash as a light source.

Then some hand pictures. These were shot the hand about 20cm from the wall, and an arms length from the camera :).

 

As you can see the shadow is not quite symmetrical in the picture, when the camera is vertical. The upper side of the ring flash is a little brighter. (But I've seen worse.) In the next picture the camera is horizontal.

I can almost hear someone asking about the loss of light in this thing. Well I'm sure you can't overpower sunlight with this one. The aluminum foil only reflects about 88% of the light (according to Wikipedia), so there is a lot of room to improve. Here are two pictures of my chili plants taken at full flash power. ISO100, 1/60s, f/5.6, about 2,5m away. First one is without the ring, the next is with it.

A few more shots. First one bare on-camera flash, then two with the ring flash on.

All images were taken with Canon 1000D and EFS 18-55 kit lens. In the last picture I also used macro extension rings.

Final thoughts: For macro shots f/10 is about the biggest f-value I can use with this. There is not that much light power, but it's distributed quite evenly, compared to many other ring flash adapters. And I intend to tweak it a little, I have some ideas. It's not pretty, but maybe I'll paint it. (It still won't be pretty.) When I replace the paper in the front with some plastic, it will be durable enough to carry around.

Any comments and suggestions are welcome!