For beam visibility you need to put a lot of these modules side by side. Think 7+ in a hexagon shape like a E07 
Do you have a C8+ with a flat white? Imagine holding 7 of them and seeing the beams in the air. They beam won’t be super bright but should still be something to behold.
one problem is, if the air is dry, and ‘too clean’, it is hard to see any visible light
it has to reflect off something to come back to the person on earth
usually that is dust or water vapor drops
green is the color the eye sees best, and yellow
so i would say green laser, but they are not very wide.
Sunnysunsun:
Yes. But instead of a 7-up TIR where the beam angle is 5-10 degrees each, I’m thinking 7 (or more) Enderman Lightcanons/Optofires The OptoFire Searchlight | BEAMSHOTS on page 3 | record-breaking aspheric LED thrower Something like this:
The problem with Enderman’s builds is that they both used a Wavien collar. According to Enderman’s posts, that boosts the Lm/Cd by 2-3x on an XP-G2 or Osram black flat. But Wavien collars are now pretty much unobtanium and were always $$$$. So, is there a way around that bottleneck using a more modern (yet affordable) led and reflector with a sufficient lm/cd? One that would still work with the cheese-grade Fasttech 100mm lens? https://www.fasttech.com/products/1606/10002523/1583700
We shall see.
A recoil design using a very large parabolic reflector would be a better idea. But all of the affordable reflectors (Edmund Scientific, kids toys, solar collectors, etc) have been tried and have failed. Bad optics = salad bowls. And for the price of a quality electroformed reflector ($2,000 US), I could just buy a used single-head SkyTrakker, or a big DMX moving-head and be done. But I don’t have that kind of cash. I have seen large glass reflectors listed on Ebay, but they’re still $$$$ and I haven’t seen anyone use one yet. And for me, that’s too much money to risk. here
I have already tried a cheap “page magnifier” fresnel lens like the ones used in COB projects on YouTube. Using a 300-watt halogen worklight as an emitter, I could focus the hotspot down to the size of the bulb itself. But I couldn’t columnate the beam or more importantly, see it. Made a great flooder and an ok thrower, but utterly failed as a beamer.
I also have an ADJ Pinspot II stage light. It’s got a “3-watt led” of some sort and uses both a TIR and a plano-convex lens. But it’s best beam angle is 6 degrees. On a very foggy night, I can see its beam for about 1000 ft (300 meters). But on a clear night, nothing. The beam is not columinated and is not intense enough. Makes a good thrower though… if you want to light a disco ball.
wle:
Yep. And Colorado is a desert. Our relative humidity is often below 10%. We do have dust and smoke, but not usually in December. And counting on fog or a blizzard is cheating. Even a street light makes a beam in those conditions.
How about using some sealed beam headlights from an old car?
I don’t think that would do it. Based on other projects I’ve seen, what I need is a super-tight columnated beam with the highest intensity I can get… times as many as I can squeeze into the budget. I know that a recoil-parabolic reflector design would be best. That’s what the Sperry/GE carbon arcs used. The problem there is cost. Every inexpensive large parabolic reflector project I’ve seen has failed because of the reflector optics. Pot lids, kid’s toys, solar cookers, satellite dishes, Edmund Scientific 12/18/24”, that thing LightSword made… they all have the columnating ability of… a pot lid. And car headlights are basically designed to spread a beam about 40’ (10m) with a throw of about 150’ (100m). Great for illuminating a road, but not great for a searchlight. Though I do appreciate the suggestion!
I’m looking for a throw of 3,000’+ (1km), with enough intensity that people can see the beam on a clear night. (Jamie wants big beam.) Enderman’s aspheric lens projects (Lightcanon, Optafire) achieved that throw. But not the intensity. They used 100mm and 120mm lenses respectively, which is big for a flashlight but tiny for a searchlight. However, the overall design was simple, effective, and inexpensive. The only piece of unobtanium was a Wavien collar, which concentrated the led intensity by 2.2x. But that was with an XP-G2 and an Osram black flat. LEDs have come a long way since then, and the Wavien may no longer be necessary. Likewise, since my goal is not max lux in the hotspot or max throw, I may be able to use a larger but less intense LED source that has higher overall lumens.
So here’s my plan as it stands:
Now I just need a cool name for this project…
Light-A-Ray? (Larry)?
Big Lumen F-er (BLF)?
Finger of God (ok, maybe I’ll save that one in case I ever have the budget for a Sperry carbon-arc)
OK, parts are on order. Here we go…
I’m going to start with an Osram CSLNM1.TG and a 3 amp CC single-mode (100%) driver from Mountain Electronics. That seemed to offer the best combination of die size, intensity, and cost for a thrower. For power, I’ve got a Mean Well 3.3v 60 amp off-line power supply. The lens will be the Fasttech 100x30mm borosilicate plano-convex aspheric (cheez-grade, but less than $8 each). And the host will probably be a 4” (100mm) pvc sewer pipe. The only thing I haven’t decided on is the heat sink. I know a fan colled cpu heatsink would work. But a decent one is around $25. Which would mean $175 in heat sinks alone if I build the large array. I think a better option will be a custom-fabricated liquid cooling system. I can make that out of copper plumbing fittings and a fountain pump and just flood-cool the heat sink. But to start, I think I’m just going to use a big block of 6061-T6 Uh-LOOM-uh-num, because I have one out on the bench right now.
Should be fun. Stay tuned.
I hope you have fun here, Dr scott Diabolical - Evil Genius!
That is quite a username to type in. 
Well if all else fails there’s this open option……… 
https://www.searchlightsofsandiego.com/rentals.html
I mean if ya really wanna attract extra attention to your unit first of course. 
PS. The FAQs are an interesting read.
Well, this definitely sounds like an interesting build. Will this be able to light up low hanging clouds? I remember when I was little, I used to see pretty fat beams of light from VERY far away shining into the clouds. I would often see them around Christmas time, but I never got to see one in person so I don’t even know what they look like. Every time I saw one it would be literally at least a mile away. I’ve always wanted to do that, shine a very bright light into the clouds. I’m thinking your build will likely be able to light up clouds. Perhaps not to the extent of those batman signals I saw as a child, but definitely enough to eek out a chuckle in awe at least, since some of my flashlights are able to just barely light up the very low hanging ones. It helps that they’re white so they’re very reflective.
We will want beamshots of your build, by the way
Yeah. but you’ll never confuse me with anyone else.
I actually found a single-head 2kw SkyTrakker for sale for $1,795. They didn’t say what was wrong with it. Or, how much time the lamp had on it. But to me, $2k for a light is the same as $20k for a light. I ain’t got that much. So neither is possible right now. …still, there may come a point in my life when I become the custodian of a 60” Sperry carbon-arc. It could happen. I have a plan.
That is the goal. Now to be fair, I can already light up “low hanging clouds” with my little 700mA pinspot stage light. But only when they’re 300 ft AGL (about 100m above ground) and it’s foggy. I want WAY MORE than that. I want you to see that beam in spite of the Christmas lights, and street lamps, and clear air. I DO want to draw attention. I do want people to see it from miles away.
Fortunately, I live in a little farm town in eastern Colorado (the uncool flat part, not the mountains). Folks out here would think a big light was “badass”. Also, I’m super-mindful of my neighbors. I only run the animated portion of my Christmas display once every 15 minutes, between dusk and 9:00 PM. I do not intend to become “that guy” with the too-big display that creates hassle, traffic, legal issues, etc. for his neighbors. When my Christmas display gets big enough, it’ll move to a commercial location and will be a drive-through experience. Likewise, I’m very mindful of aircraft. I live directly under one of the approach patterns to Denver Int’l Airport. When it’s in use, the searchlight will not be operated. Simple as that.
300 feet AGL? sounds more like fog to me 
You’re lucky to have such low hanging clouds where you live! I’m talking about Cumulus clouds. The fluffy, white cottonballs that are several thousand feet up in the sky. (I think by definition, “low clouds” are anything under 6,500 feet) obviously with fog being excluded as that’s a ground level cloud. Anyway the point is I can already hit the very very low hanging cumulus clouds just barely, but I’d love to maybe build a big spotlight that could easily and very noticeably light up clouds several miles up in the sky. It sounds like what you’re building might be able to do that. The carbon arc really is a marvel, that thing can light up ANYTHING!
That last part you mentioned about being mindful of aircraft reminds me of a friend of mine who recently acquired a laser he had lost in the past once again. He sent me a video where he was pointing it around at the sky and then he pointed it straight into a passing commercial aircraft! :person_facepalming: I was like dude do NOT do that! Not only is it illegal, but it’s very dangerous. He took it as a joke and I was like you do realize that there could be potentially 200 people on that flight, right? Now I’m not saying a laser pointer is gonna cause a plane to crash, but still… have some common decency.
He’s dam lucky he’s not getting to know Tyrone in an intimate setting.
Hey, Evil Genius, I was watching some videos on yt last night and ran into one where they reviewed a couple of Fireflies flashlights. It was a video by Matt Smith (adventuresportflashlights) from 2018. Anyway, it got me interested because he mentioned that that brand offered premium products with high performance for a modest price. So hours later, I got the curiosity to check out their website. First page that loaded contained a “featured” section of flashlights, of which I clicked on the T9R cuz it caught my eye (I’m into throwers). Anyway, the light comes in 3 different configs, 2 of which are an osram LED and the other being an SBT-90.2.
Point is the Osram emitter is the one checking out. With that LED, the flashlight produced a beam that looks like an LEP flashlight. CULNM1 10W is the LED you wanna look into. It produced 1.5km of throw at just 900 lumens, and as I said previously, the beam looks like an LEP light, so even though it’s only 900 lumens, it produces a very focused “laser” beam that’s easily visible and very long. Not that hard to drive either, I think it takes just 6amps for max output. This LED is mounted on a single 21700 flashlight so you shouldn’t have any problem with a custom build. Only downside is, the emitter seems to be quite inefficient, so output drops a bit even if not prompted to by heat management. Also seems to get hot rather quickly (flashaholic mentioned this on his YT review. Although, I doubt any of this will be a problem since you’re only gonna be blasting the lights in bursts, so it sounds like this LED fits ur application perfectly. Now I don’t know how much they cost, but I don’t think they should be too expensive.
They were pretty successful w/ the vertical lights in this story. Probably outside the budget.
If you can find a 90cm mirror all you need is a 100w HID kit. All up cost about AUD$280
1km
3km
Sitting on my living room floor, I’m already 4,992 ft above sea level. So yeah, in winter we do get some LOW clouds if the winds are blowing “upslope” from east to west against the mountains. Normal cloudbase for cummies (when there are any) is around 3,000 AGL. This side of Colorado is a desert, so they’re kinda scarce. But yeah… huntin’ zepplins…. that’s the goal. And yeah, it’s a felony and a Federal crime to point a laser at an aircraft. Plus, it can be dangerous. Commercial laser shows require an FAA variance. There’s a form that must be submitted, etc. Conventional searchlights are OK as long as you’re not being a douchebag and hotspotting aircraft.
The Osrams max out at around 4.3 amps per Djozz’s posts. I went with a 3-amp driver from Mountain electronics b/c it was $4.60, and a 4-amp driver would have been $20.00. Likewise, the led was about $6.50. It’s not anywhere near the SBT90.2. But it doesn’t cost $130 from Mouser either. And, it’s still pretty much the king of intensity for 1mm2 dies. Enderman’s “Optafire” & “Lightcanon” are the two projects I’m emulating. My design won’t be as powerful as his. But it’ll be cheaper and that will allow me to just build more units and gang them together. I’m not looking for numbers with this project, so I don’t need a single giant emitter. And yeah, I’ve seen those videos. Every encouraging, even though I’m going with a 100mm aspheric lens (if Fasttech ever ships it).