Dive Blacklight (UV Light)?

[Rev. Blade]

Take a look here.
http://www.nightsea.com/home.htm

That's the site that got me going on the underwater Black Light idea. Cool videos! The actual experience on a dive was less thrilling. I plan to try my DIY filter for my Light Cannon at some point, but fewer things light up under Black Light than I'd hoped. Perhaps it'd be fun for someone who does a lot of night dives, and wants to try something new.

 

[LarsB]

Dear divers,

I read about using an ultraviolet lamp during night dives in the book "Dolphin Island" from Arthur C. Clarke.

Such an ultraviolet ("black light") lamp is supposed to give a spectacular view underwater by way of bio-fluorescence.

A colleague of mine found the following videos which demonstrate this effect:

youtube.com/watch?v=meczKORhpmo (1:20)
youtube.com/watch?v=ZueVxQ-tIYU (1:59)
youtube.com/watch?v=AjPjiYyia_Q (7:17)

In the meantime I found a suitable (standard white) LED diving lamp and a suitable UV LED and was able to modify the lamp accordingly (see also the pictures attached here below).

Parts used:

(1) "LED LENSER" diving lamp (up to 60m / 7 bar) with 4 AA batteries (6 V)
(2) Drop-In - Module 1 Watt UV LED 390-405nm (see taschenlampen-papst.de/P60-Drop-In-1-Watt-UV-395-400-nm-LED-Schwarzlicht-Qualitaetskontrolle-Rissdetektion-Leckageortung-Forensik)
(3) Arctic Silver Thermal Adhesive (see arcticsilver.com/pdf/appinstruct/asta/ins_asepxy.pdf)
(4) Resistor 8.2 Ohms 5% 5W (actually it has around 8.5 Ohms, which is perfect in order to limit the current to between 0.27 A and 0.28 A, which corresponds to 1W at 3.6 V at the LED, when battery voltage is 6 V) to replace the original resistor of 3.3 Ohms

Costs: 65€ + 15€ + 11,50€ + 0,70€
Shipping: 12€ + 2€
Total: 106,20€

Have fun!
LarsB

 

[Blazinator]

Copied from another thread I posted - see black light vid and info at end:
Biofluorescent video and GC East End trip report
June 5 - 12th - The four of us got off the plane and immediately did one of my best all time dives at Eden rock - lots of bottom time, schools of jacks circling us, swim throughs, Fairy Basslets all around (love those colors!) etc etc - ALL for price of a tank rental.

Stayed at The Reef resort and dove with Ocean Frontiers - wayyy professional, wayy courteous, set up and cleaned gear for you, way accomodating to our changing schedule - top notch. The main reason I went with them was that they provided me with AL 100's and nitrox. Red Sail will only give you 72's. If you are big like me, and you spend lots of $ to get underwater for a prescious few hours of the week, why would you dive with an operation that limits you to only 1/2 hour BT? Our second dives were always about an hour. OF even gives you a personal print-out of all your dives, the site name, with your depth and BT at the end of your diving week.

If the wall dives on SE end are lesser than the North Wall, then I don't think I could have handled the North wall dives - too awesome. Imagine swimming through a cavern with a deep blue opening at the end, then exiting the opening at 100 ft to hover over an abyssal trench only to follow a vertical wall of wonder:




All the dives were way cool. I think the biggest thing for me was the canyon like structure of Cayman diving. The "big-ness" is what I loved compared to the Keys or Hawaii (although Molokini Crater's back wall was awesome). Almost every site had deep cuts and caverns. The silverside bait balls were so mesmerizing.

Topside was hot that week, and water temp was 86 - 87 at surface and 84 @ 100+ ft. Seas were pretty good to swelly on the SE side, and flat on the north - reverse of what I expected. I really wanted to shore dive Anchor Point and Babylon, but had no time, although I snorkeled to the wall at Anchor Point to scope it out (five minutes from Reef resort). Idyllic site for its remoteness.

Night dive at Sunset Reef, in front of Ocean Frontiers - super easy for new divers:




Night dives are cool, but add a black light filter to your monster HID light, and you get to see a hidden world WITHIN a hidden world.
There are proteins in the bodies of many species of coral, jellyfish, anemones, certain kinds of fish, and even nudibranchs (that eat anemones to pass their GFP into themselves) that fluoresce under UV light. Most of the time it is Green Fluorescent Protein (GFP), but sometimes you see red and orange fluorescence, and if your lucky, you'll see a coral displaying both green and orange (some brain coral and soft corals will do this).

The fluorescence shows up much brighter in actual viewing than the video can record due to the camera's auto-equalizing of light levels, so the actual scuba diver sees an unreal light show. Some corals fluoresce so bright that it literally looks like neon is inside, as the electrically charged photons of invisible UV light come back to your eye as energized visible light.

My light is a 24 watt HID that outputs a whopping 1750 lumens which is almost 40 times brighter than a large Mag Light, and some of that light is UV light. It even cures my UV glue in seconds in my shop (I'm a polymer scientist in UV resins). So I bought a dichroic "Wood's Glass" filter from Roscoe (through a theater lighting supplier) and fabricated a snap-fit ring to fit my light, and you see the results above.

Stingray city was well worth it, the Reef resort is a blast to snorkel under the pier at noon when they feed the fish, accomodations @ the Reef were great for the price ($1100.00 pp including RT airfare through AppleVacations), and the "Over The Edge" restaurant was excellent. We saved lots of $ by bringing spinach and wheat wraps and rice to cook in our room, and all the rest of our groceries were decent priced at the Fosters market. All in all, it was fun, but not for a non-diver unless you stay at 7Mile Beach. I would seriously consider Cobalt Coast next time for my non-divng wife.

 

[iHeartScuba.com]

very cool Blazinator!

 

[LarsB]

A first night dive with this lamp at the Oostvoornse Meer was not very convincing, first of all because there was almost no life to see in the first place, second because the visibility was low, and third I suspect that the wavelength (around 400 nm, i.e., still pretty much in the range of visible light) and power of the UV LED was suboptimal.

I therefore modified a second diving lamp, the "Underwater Kinetics UK Sunlight C4 eLED" (for about 120 Euros), with the best UV LEDs available on the market (with a wavelength of 365 nm), two Nichia LEDs of type NCSU033B (see also UV-LED/Nichia Corporation) ordered directly from Japan, for about 82 Euros per piece (plus customs VAT of 31 Euros).

The results are indeed much better than with my first attempt; when testing e.g. with some Euro bills, much more features become visible than with the first lamp. The range of the lamp is also much greater (tested at night with a fluorescing target at the end of my garden).

Modifying the "UK C4 eLED" diving lamp is straightforward: remove the white LEDs, and glue the new UV LEDs to the same place (e.g. with Arctic Silver Thermal Adhesive).
The electronic circuitry in the lamp provides a current source which can be configured to several different values (e.g. 0.7 A, 1.0 A, 1.3 A).
I left it in the "1.0 A" configuration it originally came with.

Although using the UV LEDs in parallel is not recommended in their specifications, the electronic circuit in the lamp left me no other choice (unless by modifying/duplicating the circuit, for which there is not much space in the lamp). Fortunately, both UV LEDs had very narrow tolerances, while one drew about 0.5 A, the other took about 0.52 A, which is still well within the specified limits.

Should you have any questions, I'd be glad to answer them.

 

[dolesorchard]

Contact Bas Noij on here, he does UV night dives on Bonaire. We did one UV dive with him last year, it was very interesting, he attaches a UV filter to your mask, so all you see is the flourescence, everything else is black. The first time a tarpon swims by, everything disappears. Most of the corals are flourescent, as well as the anemones and fire worms. Definately worth doing once, don't think I would do it again.

 

[Fuzfuz]

Hi. I would have to vote for the Night Sea. I was hooked by the videos and saw a diver with one on a liveaboard. It really makes night dives worthwile. I've only used it in California but really makes the fluorescense stand out in the little cup corals. I'm sure in tropical waters the effect would be awesome.

Andy

 

[LarsB]

A dive buddy and work colleague of mine found the following video which demonstrates the bio-fluorescence under water:

YouTube - Fluorescent night dive @ Grand CaymanCY-FL-Anemone!!!Halo!.MOV (1:20)
YouTube - Biofluorescent Night Dive # 2 (1:59)
YouTube - Biofluorescent Night Dive - Sunset Reef, East end of Grand Cayman (7:17)
or Biofluorescent Night Dive – Sunset Reef, East end of Grand Cayman | Led Dive Light Reviews

 

[Doc Harry]

Has anybody seen an underwater blacklight (ultraviolet light) for sale? I know many corals and things are fluorescent so I was wondering if a uv light would make them glow with strange colors -especially on a night dive. Any ideas?

WOW! What a great idea?

Are you a 70s stoner? Just asking...

I'm going get some of this stuff and try it down in Cozumel. What an idea!

 

[LarsB]

Contact Bas Noij on here, he does UV night dives on Bonaire.

Thanks for the hint!

I sent him a PM and now I'm waiting for his answer.