Want to build a macro ring light using LEDs

[srvctec]

I was wondering if anyone could tell me if these LEDs would give a nice wide beam pattern at about one to 6 inches without a lens- just the bare LED. I want to build a macro ring light with 6 - 12 of these LEDs using this driver. Is there a better source for the driver?

 

[Meduza]

That is the Batwing luxeon I, it will not give you a smooth pattern, but a quite wide and weird pattern in my opinion...

Go for a Lambertian instead if you want to go the Luxeon way.

Or get modern and go with Seoul P4's.

 

[srvctec]

That is the Batwing luxeon I, it will not give you a smooth pattern, but a quite wide and weird pattern in my opinion...

Go for a Lambertian instead if you want to go the Luxeon way.

Or get modern and go with Seoul P4's.

Thanks, I was afraid of that- I've never dealt with a batwing before so wasn't familiar with the beam pattern. The only reason I wanted to use these was because of the price (.75 each with CPF discount). With P4's, I won't be able to afford to build the thing. :ironic:

 

[Calina]

I guess you want to do macro photography. You might try to build what you want by using 5mm LEDs. They should provide enough light at such a short distance. You might have problems with the color rendering though as the color temperature might not be optimal.

 

[dulridge]

This article might be of interest

http://www.dansdata.com/ringlight.htm

Donald

 

[Nils]

If on the cheap have a look at the K2 on star at Kaidomain it's 2.75$. Don't know how they will turn out (pre or post ttfl) but I have one on the way to test it.

I think problem with the 5mm's would be that the beam pattern would not be very even as most have kind tight "hotspot" with lots of rings. At close distance this may be quite distracting so a diffuser would be needed.

 

[Meduza]

The Kaidomain K2s is the "old" K2s, not the TFFC.

 

[srvctec]

This article might be of interest

http://www.dansdata.com/ringlight.htm

Donald

Thanks for that link. I have searched the web for a couple of hours in the last week or so and found about every version of a ring light there is, but didn't come across that one.

 

[dulridge]

Thanks for that link. I have searched the web for a couple of hours in the last week or so and found about every version of a ring light there is, but didn't come across that one.

I'd guess Dan is a CPFer - but his site is well worth reading through with true classics like Vegemite as a heat transfer compound. He has reviewed quite a lot of lights though not so many lately.

 

[MikePL]

I've been taking photos professionally for 10 years, so maybe I will be able to help you.

The 5mm LEDs are a good solution on one condition. You need to use lots of them. BY 'lots' I mean enough LEDs to create a 70mm diameter ring without any spacing. You will need to mill or sand the tips of the LEDs in order to avoid any hotspots or color rings. This setup will work. You can make the ring smaller if you use a smaller lens. With macro photography the ring light needs to be as close to the lens as possible. For example using a 77mm ring of LEDs on a 52mm lens will tend to create a strange dark spot in the middle of the photo, when taking shots from short distances.

You can also cut out a rim out of opaque polycarbonate (pelxi or lexan, whetever the name) and glue the LEDs to it. It will diffuse light even further.

But the only concern is light output. It may be insufficient and may need long exposures. If you want to have a high depth of focus you need apertures in the f11-f22 range and this could give you shutter speeds of a few seconds.

You can also use any high power LEDs. The K2 LEDs, whether new or old are really cool. I have a few and they are more than enough for your project. You don't have to buy some P4 or Q or Z-whatever bin because you will be using many of them. In the case of the K2 LEDs you will need to buy 6 or maybe 10 of them and you will have really lots of power. But with just 6 or 10 LEDs you need a diffuser to create a ring of light and not 6 spots of light. And remember that the further the LED is from the diffuser, the more diffused the light is, so you will need to get a PVC tube and build the setup around it.

 

[srvctec]

I've been taking photos professionally for 10 years, so maybe I will be able to help you.

The 5mm LEDs are a good solution on one condition. You need to use lots of them. BY 'lots' I mean enough LEDs to create a 70mm diameter ring without any spacing. You will need to mill or sand the tips of the LEDs in order to avoid any hotspots or color rings. This setup will work. You can make the ring smaller if you use a smaller lens. With macro photography the ring light needs to be as close to the lens as possible. For example using a 77mm ring of LEDs on a 52mm lens will tend to create a strange dark spot in the middle of the photo, when taking shots from short distances.

You can also cut out a rim out of opaque polycarbonate (pelxi or lexan, whetever the name) and glue the LEDs to it. It will diffuse light even further.

But the only concern is light output. It may be insufficient and may need long exposures. If you want to have a high depth of focus you need apertures in the f11-f22 range and this could give you shutter speeds of a few seconds.

You can also use any high power LEDs. The K2 LEDs, whether new or old are really cool. I have a few and they are more than enough for your project. You don't have to buy some P4 or Q or Z-whatever bin because you will be using many of them. In the case of the K2 LEDs you will need to buy 6 or maybe 10 of them and you will have really lots of power. But with just 6 or 10 LEDs you need a diffuser to create a ring of light and not 6 spots of light. And remember that the further the LED is from the diffuser, the more diffused the light is, so you will need to get a PVC tube and build the setup around it.

I never really considered the 5mm LED for this project for the exact reasons you mentioned- It would take way too many of them and they wouldn't be bright enough anyway.

Not quite sure what you mean by building the setup around a PVC tube- could you elaborate?

I'm planning on using 8 Lux I LEDs for this project mainly due to the relative low cost of the Lux I currently and they should be bright enough at a distance of 1 - 8 inches. Another idea I'd like to incorporate into this is to mount the LEDs on pivoting segments in an octagon. It's times like this I wish I had experience in machining and the equipment to go along with that.

Here is kind of what I was thinking for the basic design. The black part will pivot around an internal frame so the LEDs can be aimed at whatever I'm shooting. This may be over engineering, but it would sure put the light exactly where I want it.

 

[mvnsnd]

I have just recently become interested in building one of these myself. In searching the net I also came across this site where the owner has done some extensive work on DIY ring lights. http://fuzzcraft.fuzzphoto.eu/ringlights.html

A good suggestion for a diffuser would be to use one of the clear discs that come in a stack of CD's and finely sand one side. Then place that on the front of the lights.

I think that one of the issues with using the high output LED's is going to be removing the heat. Perhaps several 1 watt LED's at low power would help?

--
Jeff

 

[srvctec]

I have just recently become interested in building one of these myself. In searching the net I also came across this site where the owner has done some extensive work on DIY ring lights. http://fuzzcraft.fuzzphoto.eu/ringlights.html

A good suggestion for a diffuser would be to use one of the clear discs that come in a stack of CD's and finely sand one side. Then place that on the front of the lights.

I think that one of the issues with using the high output LED's is going to be removing the heat. Perhaps several 1 watt LED's at low power would help?

--
Jeff

Thanks for that link- I hadn't seen that one yet either. That's quite the setup with the fiber optics.

I was thinking of mounting the LEDs on aluminum tubing (for the heat management) that will rotate around some sort of octagon frame as pictured above. I don't know if this will work or not.