Here is my take on a macro ring light. The concept is not new but for me need and availability have handily come together. I just bought an Olympus TG5 and housing; two of its features are super close macro and a fast frame rate, up to 20 fps. I do not have strobes but it is evident that no flash will recycle that fast.
Recently a number of ring COB LEDs have been available, popularly used on car headlights and often termed 'Angel Eyes' from a well known online market place.
I have not found a spec sheet and the ones I purchased came with a buck driver giving 350mA at ~9V from a 12V supply for all sizes from 60 to 120mm. This can easily be replaced with a XL6003 based boost driver (available from the same place) giving 650mA. I have coupled these with 80mm and 90mm ring with 21 and 22 LEDs (sets of 3 in series) which drive each LED at 30mA. Power comes from two 18650 to give 7.4 V controlled by a clickey switch and logic level MOSFET.
Drawing about 12W I recon the setup is good for 1000 lumen.
Photo show the set up, it is a bit crude, but has done a good job as a 'proof of concept' Mk 1.
Other photos show it in action and what I think may be the photo I was taking at the time. It takes more than a nice camera and a bright light to get the perfect photo but I think it shows its capabilities. This little shrimp was on a Feather Star and demonstrates the even lighting while the Cuttlefish was from a series of shots of it while constantly moved and changed colours and shows the benefit of being able to pick the perfect (well best) frame of a swimming subject from a series of shots when neither the subject or photographer are perfectly still. (Beware of shooting at 20fps, you are left with an awful lot of deleting to do).
I now fancy that the LEDs can be driven closer to 60mA, and have tested a ring for a couple of hours at 45 mA, which should give a 50% boost in output.
I would be glad to hear from anyone who knows the true max current of these COB lights.
Construction is pretty obvious with bonded Acrylic, bolts and O ring.
Mk2 is already under construction with a more 'compact and finished' look and hopefully brighter 45mA LEDs.
Mk3 might go for the 'full' 60mA and a third ring which should push it up to nearer 3000 lumen.
OK I will post photos when someone tells me how to post from Google Photos
.
Rod
Recently a number of ring COB LEDs have been available, popularly used on car headlights and often termed 'Angel Eyes' from a well known online market place.
I have not found a spec sheet and the ones I purchased came with a buck driver giving 350mA at ~9V from a 12V supply for all sizes from 60 to 120mm. This can easily be replaced with a XL6003 based boost driver (available from the same place) giving 650mA. I have coupled these with 80mm and 90mm ring with 21 and 22 LEDs (sets of 3 in series) which drive each LED at 30mA. Power comes from two 18650 to give 7.4 V controlled by a clickey switch and logic level MOSFET.
Drawing about 12W I recon the setup is good for 1000 lumen.
Photo show the set up, it is a bit crude, but has done a good job as a 'proof of concept' Mk 1.
Other photos show it in action and what I think may be the photo I was taking at the time. It takes more than a nice camera and a bright light to get the perfect photo but I think it shows its capabilities. This little shrimp was on a Feather Star and demonstrates the even lighting while the Cuttlefish was from a series of shots of it while constantly moved and changed colours and shows the benefit of being able to pick the perfect (well best) frame of a swimming subject from a series of shots when neither the subject or photographer are perfectly still. (Beware of shooting at 20fps, you are left with an awful lot of deleting to do).
I now fancy that the LEDs can be driven closer to 60mA, and have tested a ring for a couple of hours at 45 mA, which should give a 50% boost in output.
I would be glad to hear from anyone who knows the true max current of these COB lights.
Construction is pretty obvious with bonded Acrylic, bolts and O ring.
Mk2 is already under construction with a more 'compact and finished' look and hopefully brighter 45mA LEDs.
Mk3 might go for the 'full' 60mA and a third ring which should push it up to nearer 3000 lumen.
OK I will post photos when someone tells me how to post from Google Photos
Rod