Posted: Feb 14, 2007 12:21 pmThanks to everyone for their reply!
Well, I kinda got the answer to the question. On Saturday I took my HID light to a deep wet horror hole cave in Central Tennessee. It was running fine at 7w until I kicked in on high 12w to look across the top of a 300 foot pit. After 20 minutes the light color started to change to yellow orange and the bulb got very dim afterward. After I turned it off the bulb would not strike and relight. When I got home I took it apart and found that the bulb fried. It is a complicated story, but ultimately has to do with volatile organics.
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Scott, No, Not Nathans, A custom carbon fiber prototype.
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Nico, Yes, Mine is Waterproof.
Tough? Well they are put on mountain bikes and tend to survive a lot of abuse there.
As is my light, it cost $900 to build, but I got a prototype that is still in development. I am able to run it at 7w and 12w settings and the ballast is 90% efficient. My battery fits inside my helmet and the light runs for 9 hours. The whole system weighs 1.1 pounds, but put this into perspective, it puts out the same amount of light as 12 normal cave lights all turned on at once. It lights up wall details 200-300 feet away.
Thanks!, and sure, Next time I see the Old Bast----d I'll pass on the shout out.
>>>>>>>
Thanks Nathan! That is great you have one too. Whoa!!! 50W, that is like a freaking light bomb!!! That is like 3,500 lumens or having a 250w incandescent light. That is more light than having both regular car headlights on bright. I guess you use it for photography?
Yeah the color temperature is great. I also noticed that caves have lots of color in them now I can see with light that is at 5800K. We have been stumbling around with dim yellow twink lights all these years and could not see it. With the power of HID that has changed.
The light I use runs the HID full time. 7w and 12w settings. I would like to talk to you more about all this in the future.
>>>>>>>>>
JoeyS is correct. Even neon lights are a discharge light. The technology has spread from HID car lights and recently compact 10w HID bulbs started getting produced. Yes, very efficient, 60-70 lumens per watt. A typical incandescent bulb only gets 15 lumens per watt.
As for price, there is nothing stopping HID bulbs from being produced for $10 a bulb. All that is need is the economy of scale. HID headlights could be produced at the same cost as high watt LEDs. It is just there is not much demand for a caving headlight that is bright as a 50w car headlight beam.
>>>>>>>
Thanks InvSh, we had a caver decide not go with us on a big cave this this weekend just because we were going to be running our HID lights. She said that the HID lights gave her a migraine. This is true, bright lights often trigger Migraines in some people who suffer from them. I have to be very carefull not to shine my light into other cavers eyes. It will instantly blind them, like people who leave there car headlights on bright.
>>>>>>>>>>
Another point worth mentioning
One advantage is that the HID bulb has a 1.2mm gap between the electrodes. Once an electric arc ignites the gas inside it discharges photons in all directions as electrons excite the gas molecules. It takes about 6,000 volts to ignite and 60v to maintain the arc. All the light comes out of a 2 cubic mm volume, which is about as close to a point source of light as you can get. When you put a point source in the focal point of parabolic reflector, you can get an almost perfect beam of light.
LEDs have a lot advantages, but they will never be a point source of light that throws photos out in every direction like the sun. To do this the semiconductor crystals would have to be mounted on a small sphere, but even then the waste heat would be concentrated and could not dissipate and the whole thing would melt. You can focus a HID lamp just like a Wheat Light, only it is like shining 8 wheat lights all at once. When you see a cave lit up with this much light it is amazing.
Well, I kinda got the answer to the question. On Saturday I took my HID light to a deep wet horror hole cave in Central Tennessee. It was running fine at 7w until I kicked in on high 12w to look across the top of a 300 foot pit. After 20 minutes the light color started to change to yellow orange and the bulb got very dim afterward. After I turned it off the bulb would not strike and relight. When I got home I took it apart and found that the bulb fried. It is a complicated story, but ultimately has to do with volatile organics.
>>>>>>>
Scott, No, Not Nathans, A custom carbon fiber prototype.
>>>>>>>>>
Nico, Yes, Mine is Waterproof.
Tough? Well they are put on mountain bikes and tend to survive a lot of abuse there.
As is my light, it cost $900 to build, but I got a prototype that is still in development. I am able to run it at 7w and 12w settings and the ballast is 90% efficient. My battery fits inside my helmet and the light runs for 9 hours. The whole system weighs 1.1 pounds, but put this into perspective, it puts out the same amount of light as 12 normal cave lights all turned on at once. It lights up wall details 200-300 feet away.
Thanks!, and sure, Next time I see the Old Bast----d I'll pass on the shout out.
>>>>>>>
Thanks Nathan! That is great you have one too. Whoa!!! 50W, that is like a freaking light bomb!!! That is like 3,500 lumens or having a 250w incandescent light. That is more light than having both regular car headlights on bright. I guess you use it for photography?
Yeah the color temperature is great. I also noticed that caves have lots of color in them now I can see with light that is at 5800K. We have been stumbling around with dim yellow twink lights all these years and could not see it. With the power of HID that has changed.
The light I use runs the HID full time. 7w and 12w settings. I would like to talk to you more about all this in the future.
>>>>>>>>>
JoeyS is correct. Even neon lights are a discharge light. The technology has spread from HID car lights and recently compact 10w HID bulbs started getting produced. Yes, very efficient, 60-70 lumens per watt. A typical incandescent bulb only gets 15 lumens per watt.
As for price, there is nothing stopping HID bulbs from being produced for $10 a bulb. All that is need is the economy of scale. HID headlights could be produced at the same cost as high watt LEDs. It is just there is not much demand for a caving headlight that is bright as a 50w car headlight beam.
>>>>>>>
Thanks InvSh, we had a caver decide not go with us on a big cave this this weekend just because we were going to be running our HID lights. She said that the HID lights gave her a migraine. This is true, bright lights often trigger Migraines in some people who suffer from them. I have to be very carefull not to shine my light into other cavers eyes. It will instantly blind them, like people who leave there car headlights on bright.
>>>>>>>>>>
Another point worth mentioning
One advantage is that the HID bulb has a 1.2mm gap between the electrodes. Once an electric arc ignites the gas inside it discharges photons in all directions as electrons excite the gas molecules. It takes about 6,000 volts to ignite and 60v to maintain the arc. All the light comes out of a 2 cubic mm volume, which is about as close to a point source of light as you can get. When you put a point source in the focal point of parabolic reflector, you can get an almost perfect beam of light.
LEDs have a lot advantages, but they will never be a point source of light that throws photos out in every direction like the sun. To do this the semiconductor crystals would have to be mounted on a small sphere, but even then the waste heat would be concentrated and could not dissipate and the whole thing would melt. You can focus a HID lamp just like a Wheat Light, only it is like shining 8 wheat lights all at once. When you see a cave lit up with this much light it is amazing.
I just replaced a shot by Bob Biddix of on Berta Whitesides. Guess that shows how much I liked Nathans' shot of the Rumble Room. Hope I don't get in trouble for replacing Berta on my desktop. 
