75aH batteries and refractive flashlight

nanoWatt

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I have a couple of deep cycle, 75AH batteries (look like car batteries) that each use a 40W solar panel and charge controller (to prevent overcharging). I know that they will arc if I accidentally short the terminals, so they've got some serious push, and can be drained to like 30% or lower. I think they are lead acid.

Anyway, can someone make a recommendation on which model or type of bulb would be recommended with them?

I want to do a 3-bulb setup, each with it's own reflector much like some of the WolfEyes 3-bulb setups. However, I want to experiement with making a refractive flashlight. It would be handheld, but would have a power cord to the battery and possible circuitry. I will use 1 battery.

I need to make sure that this below is feasible:

The refractive setup would be like a reverse refractive telescope. The 3 bulbs are focused onto a central reflector, and then reflected again off a larger reflector that surrounds the bulbs, and then projected outward. Two lenses could then collimate the beam if separated by their focal-lengths.

I wanted to do a diagram in Bryce, but didn't get to last night. I would like to do a beam of heat and light, so I'm thinking halogens. I can put cooling in the handheld unit, such as liquid cooling that would run behind the reflectors.
 
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My only concern is that a central (backwards facing) reflector/refractor would create a ring of light instead of a spot of light (it would in essence block the beam path). I need to figure how to make the 3 light sources be as if they were coming from one source, or rather, turn the 3 emitters into a single beam.

Collimating with 2 lenses should then give it excellent throw. According to Wikipedia, "Collimated light is light whose rays are parallel, thus having a planar wavefront." While I may not be able to get this totally with incoherent light, I may be able to maintain a column of light as long as possible.

The halogens I have seen are 120V, 250W each (with a nice yellowish-white glow, bright as hell). So finding a 12V halogen might not quite give the same power. I want this unit to be somewhat portable, though lugging around a 20-30 pound battery isn't really "portable" but I can put it on wheels. I might come up with a clever name like "the Schwartz" or something for it.
 
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they've got some serious push, and can be drained to like 30% or lower. I think they are lead acid.

flooded lead Acids I bet...if their sealed your batteries wont last too long draining them to 30%:sick:

interesting idea though, good luck on the liquid cooling part...so far no one on the forum have created anything of that sort yet ;)
 
You could get an estimated 3600 bulb lumens from an Osram 64625 at 12V, though it won't be overdriven to the lovely white color it can achieve. At that drive voltage it would draw about 9.1 Amps for 109.2 Watts.

If you could tolerate hauling both of those batteries around you could go with the 250W Osram 64655. You could get over 10k lumens from one of these.

If you must stick with 12V and want to go higher than 100W/ bulb, then you are in uncharted territory. Here are a few options:
GE 20575
GE 20576
GE 20577

These are available on bulbconnection.com

Good luck and let us know what happens!
 
I can use a transformer or power inverter if needed, to get over 12V, and sacrifice some current.

How difficult are the Osram bulbs to focus?

Is there as much heat as light generated?

I'm going for a beam here, with possibility of spreading it out by changing the distance between the lenses.

I guess with my setup, using three Osram 64625 would probably be difficult.

I was looking at different bulbs here: http://us.100y.com.tw/pdf_file/OSRAM(PhotoOptic).pdf

They have a studio bulb that gets an insane 1,700,000 lumens at over 200 volts.

If I were to go with 120V, I could have more options in my bulbs. However, I do like the cost of those 64625's.

You could get an estimated 3600 bulb lumens from an Osram 64625 at 12V, though it won't be overdriven to the lovely white color it can achieve. At that drive voltage it would draw about 9.1 Amps for 109.2 Watts.

If you could tolerate hauling both of those batteries around you could go with the 250W Osram 64655. You could get over 10k lumens from one of these.

If you must stick with 12V and want to go higher than 100W/ bulb, then you are in uncharted territory. Here are a few options:
GE 20575
GE 20576
GE 20577

These are available on bulbconnection.com

Good luck and let us know what happens!
 
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What about a couple of carbon rods sharpened in a pencil sharpener? Good old carbon arc lights. Clockwork mechanism to keep feeding the elctrodes. For messing around use a couple of pencils and a pair of clamps. The softer the pencil, the better, less clay in them which doesn't conduct all that well

Lots and lots of lumens and cheap consumables - rip apart a couple of D cells for the electrodes if you want to get fancy. Most old searchlights used just such an arrangement. You can still buy the electrodes for electric brazing rigs. 40 years ago most cinema projectors used arc lights.

Lots of fun, lots of light, lots of UV - wear eye protection.
 
I can only speak for the 64625 because I have never tried the other bulbs I listed or the ones you mentioned. They do required a larger reflector than most hotwire bulbs commonly in use because of the larger filament. If you have an idea of the beam angle you are after I know you could calculate the required reflector size to achieve it given the filament length. For tighter focusing you might go with a bulb that has the filament oriented the other way, or transverse. If you want to use 120V you could go with this 1000W bulb for 27,000 lumens. That is already drawing 1000/120=8.333 Amps.

The power inverter capable of delivering 3000 Watts will run you almost $400, but to power a bulb producing 1.7 million lumens would pose a serious challenge to the pocketbook. I can't find the bulb you are referring to because your link isn't working for me, so I don't know the current draw. Nonetheless, I wanted to point out that really high currents like you are proposing will demand large equipment.
 
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