I was thinking of taking a 100 watt ebay LED and building a light around it and putting it in a Thor Cyclops.
This way you would get a whole bunch of lumens in an LED form factor pushing through the massive Thor reflector. If the focusing was done correctly it could provide amazing throw and have the benefits of LED (as oppose to HID).
What do you guys think?
Thoroughly enjoyed watching that video. You’d think that guy had built a thousand of those things. I’m sure those with experience in large reflector lights will chime in with advice as I have none. But if you do, I’ll follow your thread. That’s one large reflector!
You will never get amazing throw with 100w cob.
Was thinking the same thing. So, is there a point of diminishing returns when it comes to reflector size?
Throw is distance. In meters.
Illuminance in lux.
If luminous intensity is fixed, to have 2 times more throw you need 4 times more lux.
If lumens are fixed, all depands from cd/lm.
Cd/lm depands from die area (from square of linear size in mm`s) and from reflector size (if we are talking about parabolic reflector, 1*1mm die with 20mm reflector will have same cd/lm as 2*2mm die with 40mm reflector).
So, if you have fixed reflector size, you can use 100W cob with 729mm2 die, receive X cd/lm, X*lumens lux and sqrt(cd/X*lumens) throw.
Or XHP70 led with 49mm2 die, receive 15X cd/lm, 15X*lumens lux and almost 4 more times throw.
Of course such calculations are very rough, XHP70 is only 32W and etc. (But have much better lm/W that cob leds from china).
But main idea is that the only characteristics for choising led for throw is lumens/sq. die size.
Thanks for the informative post. Maybe putting in a few XHP70s close together in the center of the reflector then would work?
Try to cool 32watts for beginning…
This especially! Those 100w COB’s don’t produce nearly as much heat as a single xhp70 (at least in my experience). Probably because the cheap ones don’t produce nearly 100w of light. I think the best lighting option for one of those Thor Cyclops lights is to put an HID setup inside. Every one that I’ve seen has a halogen bulb, so upgrading to a true hid will make it a monster! Just got a figure out how to fit a ballast and batteries in the housing.
+1 HID if you want throw
Ya I already have a 55 watt hid and ballast in my Thor light and its definitely a very powerful light… but I wanted even more power and the convenience of LED.
Maybe I should just try to get an even more powerful HID in there.