Substitute for ring flash
 

Here is a simple lens torch I made to illuminate subjects on my 60mm macro lens, as I found I often blocked out the light when closing in on the subject.

You require a small soldering iron and to be able to solder.:)

To make it you require enough 3.0 volt LEDs to cover the edge,mine has about 60, buying them in a bulk pack they are very cheep, I used ultra bright white LEDs , you have a little white balance to adjust in the shots but they are normally very good.

Stiff plastic, card could be used but plastic is more durable.
I recommend you experiment to get the correct fit and length of tube, make it as long as you can, when looking through the viewfinder it should not be in view

Copper wire, I used a single strand of mains twin and earth 1.5mm

A battery holder.


Method

1: cut a strip of the plastic about 2 inches wide, depending on your lens it may require to be wider but you can check later. Wrap the plastic around the end of your lens like a lens hood. Cut it length so that its just a nice fit without falling of, you can use a bit of tape to hold it in a tube shape while you get it right.

2: put batteries in your holder and find out which way round the LEDs work, the only work connected one way. Note down the connection.

3: Using a bit of single strand copper wire make one ring that fits inside the plastic tube, and one that fits round the outside of the plastic tube, solder the ends of the rings, they can be a slightly loose fit but assembly will be easier if they are good.

4: Fit the battery box, mine had 2 wires under it, make small hole for them to go through, bend one wire up towards the front the other towards the back. Fit your copper rings to the inside and outside connecting one to each end of the batteries, install the batteries for a few minutes to test an LED, slip it over the end so that one wire goes each side of the plastic and it should illuminate, now all LEDs must be mounted in the same manner, either long wire inside or outside depending on how the first one worked.

5:remove the batteries, start fitting the LEDs side by side, soldering each one as you go, trying to keep them all pointing straight forward, clipping the excess wire off as you procede.

Your done, simply install the batteries and they will all light up, the batteries will last a long time, slip it on the front of your lens and off you go.

I hope the images help illustrate the idea and demonstrate the light pattern, its nice full flood that gets into all the wee spaces reusing shadow.

Have fun, Bob

OOOh! I like it Bob, that's a brilliant idea and you wouldn't have to wait for it to charge. I know what my next project is going to be.
All I have to do now is source some Led lights. I can't wait to have a go.
I could take apart all my garden lights and nick one bulb out of each one:D but I don't think Mario would be very happy. LOL!

Parts
 

This link to Fleebay may help 50 for £5 ultra bright 3.volt Leds

http://cgi.ebay.co.uk/50ps-10mm-1500...d=p3286.c0.m14

Bob

Thanks Bob the cheapest I could find was 49p each.

Bob, what is the difference in 10mm 2500mcd and 10mm 1500mcd, the 2500mcd are in a pack of a 100.

mcd
 

Hi Christine I'm sure the MCD is the output

"The unit of measure commonly used to describe LED intensity is the millicandela (mcd), 1000 millicandela equals 1 candela.

10 mm is quite big and 50 would probably do it, but if your making 2 :)

I think you have the bug :)

Bob

Thanks Bob, I will go for the 50 of the 2500 if they are brighter, I counted how many you had in the one you made and thought I would be short.

Looks fascinating Bob. I wish I'd have seen it before I bought my ring flash - much cheaper, and I would imagine just as effective.
How about a refinement - 2 switched circuits, one for each semi-circle of LEDs - so you can have modelling light if required?

LEDs
 

Christine, my LEDs are 5mm so you will require less if using a bogger diameter, your battery will not last quite so long with the brighter output but LEDs take hardly any current so I'm sure they will last a long time anyway.

Gordon, good idea it could be that each alternate one is iluminated to maintain the ring pattern. I doubt very much if this will be anything like as bright as a flash gun\ring flash but I found it delivers a softer more efective light for close macro, and when you move in close if the subject is live, theres no bright sudden flash to scare it off.

Bob

I think you'd need some asymetry to the array - what I had envisaged was directional light so that you could introduce some subtle shadowing to give a more 3D feel than the ring flash light does. (My ring flash can do this - you can turn up or down each side, or have even shadowless lighting, but it is a bit flat)

Bob I have just received the leds and will be doing the build sometime next week when I have time, I can't wait to see how they work.

Excelent, you can test one out by attaching it to a battery of course, and now that natural light is starting to fade a bit you will get even more use from it, experiment at night taking shots of flowers etc, its good fun :-)

Bob

I decided I couldn't wait until next week to start this project, so here is what I have done so far.

I bought 50x 10mm Leds off ebay. Total cost £4.95 with postage.
Spare 2 core Speaker wire.
Black gaffa tape
Chrome Tape to use as a reflector.
The cardboard tube from an empty gaffa tape role, this fits nicely around the Canon 100mm Macro.
A straight Pin
Long nose pliers.

Photo 1.
Mark and pierce holes with the pin 11mm apart in each side of the speaker cable and push the positive pin though the positive side and negative through Negative,

Photo 2.
Align all LEDs so they are the same height and bend the pins over so they don't touch each other.

Photo 3.
Put a small strip off gaffa tape over the bottom set of pins to give some insulation.

Photo 4 & 5
Cover cardboard tube with black gaffa tape on the inside and outside.
On the top edge put a small strip of chrome tape to act as a reflector.
Wrap around the LED's so the bulb is resting on the reflector and hold down with more gaffa tape.
Cut a 1/2" wide piece of cardboard the length of the leds plus a little overlap, cover this with chrome tape. Wrap this around the outside of the bulbs and pull tight and join. (This is the outside reflector).
Finish off with Black gaffa tape to hide all the pins and attach the battery holder. I have yet to do this as I have only borrowed one from something else.

I think I need to do some more modifications, if I go to close to a subject I get a doughnut effect so the subject is not lit up, to far and it is only useful as a fill light.

Christine a very inventive solution well done for lateral approach to soldering. I can see why you are getting the illumination problems. If you look at my build you will see that each leg goes each side of the tube, there were 2 reasons why it was done that way, one was to isolate each contact, the other was to ensure that the LEDs were mounted pointing directly forward, looking at your mount they are pointing outwards away fron the mount, giving you the wrong pattern. Is it possible to straiten them up.

Bob.

Bob, on the finished ring the bulbs were facing forward, I put a tight sleeve with reflective chrome tape around the outside of the LEDs to straighten them up. That wasn't the problem what I found was if I went any closer than 8" the center of the frame wasn't lit up, it was in shadow.

I only had time to post 5 photo's on Thursday, I didn't realize I hadn't posted the finished ring. Now that my Archery outdoor season has finished I am going to see whether I can get a better angle maybe pointing inwards slightly to make a snoot shape with two rows of lights..

Finished light
 

Hi Christine, the finished unit looks very good its just a pity the results are not as expected. I think it must be down the actual LED lens, mine are smaller in diameter and the light pattern is very useful. I must have been lucky mine worked first time, there are newer leds that give even more light but are fairly expensive, I'll see how the budget goes :)

Bob

Bob, its a shame they don't seem that bright with 6volts, I did try briefly with a 9volt pp3 and they are very bright but I don't want to burn them out by using the wrong voltage. I am still thinking of how I am going to make the snoot shape. I don't want to make it out of cardboard it will be to flimsy. I will get there.

I have now made Mark 2.

I stripped everything down and carefully parted the wire so as not to break the pins. I ended up with one wire all positive and one wire all negative.
I decided to use the original tube because it fits the end of the lens nicely. I then put one wire with one set of legs on the inside of the tube and one wire outside, and taped them in place. I put a hole in the tube and pulled the end of the wire through ready for connection.
I slightly tilted the bulbs inwards to allow me to get closer to the subject without any doughnut effect.
All now works brilliantly accept for one major problem the white balance I can't seem to correct this either in camera or in software without losing all colour. :(
Example below.
1st Photo finished ring
2nd photo with LED's
3rd photo with my original home made ring flash using the onboard flash

Christine,

Maybe worth a post re your White Balance problem as a 'HELP' in the Photography Forum in the hope of attracting attention.

I just had a look in Bobs gallery and see he uses a Nikon D300, and I cannot help as I do not have any LEDs.

Don

Thanks Don, I did try various settings in the camera but couldn't get rid of the blue. I used my 350d for macro so I am going to try my 40d to see if I get it any better

I have it sorted I can do the white balance in DPP it allows me to use the eyedropper tool to pick the white white balance.

Love it, now that is cheap, thanks for posting.

I have decided that the light from the led is not strong enough on its own, I still have to use another light source to get sufficient light, it works great as a fill in light.
The first ring flash I made earlier in this thread utilizing the pop up flash is still the winner as the only lighting for macro. I can use it up to f16 ,250s with no extra lighting.

Another solution would be to use manual white balance - is take a picture of an 18% grey card illuminated by the leds and then use that to set the white balance - that way you shouldn't need to adjust each image seperately in DPP

Thanks Gidders, I had completely forgotten about that feature in camera.

:confused::confused::confused:

Sorry a senior moment, it was in a previous thread DIY Ringflash

http://www.worldphotographyforum.com...?t=1860&page=4

I have tried your Quick and dirty method and it works great, thanks for that tip.:D

macro light
 

What a great idea Bob,il certainly give it a try,could be just the job for illuminating micro moths at very close range.all the best Bri.