Reposted from LN. Hope somebody found it interesting, maybe even help me a little with this idea.




As mentioned earlier on LN forum I preparing for cosplay. One of problems to solve are tanhì (bioluminescent dots).
In human case real bioluminescent may be dangerous thus We need to find different way. This topic is intended to collect all possible solutions and chose best one. Basically only there are four main ways to have tanhì:

1. Reflective - white paint, silver paint or true reflective material (only for photos with flash).
2. Glowing - everything that emit light.
3. Projection on skin (3D mapping, etc), not very practical in real live.
4. Photo manipulation (photo shop, gimp, etc) - the best results on internet.

Reflective is the simplest solution, just grab white marker and paint. I'll chose that way when other fails. Glowing sounds best for me, but still searching for optimal solution, there are so many ideas to use...

1. Fluorescent - grab invisible (UV) light and emit visible (blue, yellow, white, ...) light.
   All You need is fluorescent pigment and UV light source. UV pigment can be used as a paint (see Jane’s guide) or tattoo ink (see Eana Unil's posts)
   .
2. Phosphorescent - store light energy and release it later.
   Same but with phosphorescent pigment. What's the different? Phosphorescent pigment may glow few hours in complete darkness. Sadly, light intense are very poor and dots should be big to notice. Basically city lights can kill phosphorescent effect without much effort.
   .
3. Chemiluminescent - chemical reaction that emit light, see lightning bugs.
   Glowing solution are available as glowing stick, used for fishing. Sadly available sticks are way to big. And thrust me, You shouldn't open that stick and use mixture as paint. Glowing solution are caustic and may be toxic. It's not the best substance to play with.
   .
4. Electroluminescent 1 - phosphor plus high voltage = light.
   EL wire is very nice light source. With outer diameter of 2mm can emit light at any direction (need opaque cover to stop unwanted light between dots). Sadly, driving voltage is as high as 100V. Not danger when insulated but not nice when insulation fail. And personally I'll never try to put that around whole my sweaty body. Btw, not compatible with body painting. Full costume required, face costume may be problematic.
   .
5. Electroluminescent 2 - LED (light emitting diode) or actually LOL (Lot of LEDs).
   Another solution not compatible with body painting. Full costume required, face costume may be problematic. LEDs are small, energy efficient (in some applications too much efficient) but need a lot effort to solder them all to fine wires. First tests with regular LED tape already happened but that tape are rigid and not elastic at all. I have problems with that tape on my hands and cannot imagine wiring that all over my body/costume. Only idea that looks promising are to solder each LED to thin copper wires and sew that wires to the fabric. Lot of work but may give nice effect.
   .
6. Electroluminescent 3 - any light source and fiber optics.
   Similar to two solutions above. This need separate light source and fiber optics cables to transfer light to individual dots. Sounds more rigid than hand made soldering but at least better than LED tape.

"Lot of LEDs" is the solution I trying to use. Sadly no glowing dots over my face because I don't have any idea how to glue LEDs and hide wires. Maybe LED implants or fiber optics implant within next decade? On the other hand, white LED at 20mA will be noticeable even through layer of fabric under powerful street lamps. 1mA per LED sounds reasonable for darker environment like cinema, where I plan to perform my cosplay. With good battery and proper dimmer I may be the star of each event, spreading more light than regular 15W incandescent bulb

Do You have any other solutions?
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Thanks Toliman, I forgot about radioactive light sources. As dangerous as real bioluminescent by glowing bacteria.

TEA: I need space for store documents, phone, wallet and keys but don't have slaves to hold my items and follow me There are few options to store my items: backpack, hip bag or kidney bag. Any of them allows me to store battery pack. Just need to figure how to pass wires through costume fabric.
Sadly bag/backpack limits me to play only as avatar driver, not real Na'vi. But who really cares about that details.
Alternatively I can hide batteries along the entire length of the tail, same way as Jane MacMillan add extra weight to plastic tube.




BTW, Two new solutions found!
1. LEDs on fabric tape, by adafruit.

- Expensive and not stretchy but at least flexible. Made of fabric plus two stainless steel wires. 20 LEDs per 1m, comes in 1.5m string.

2. LEDs already soldered to copper wire, by adafruit.

- I may fold wire between each dot and sew individual dots to my costume. That extra amount of wire should give me enough elasticity. Wires and sewing may be visible through fabric but hope they don't show up.

EA, thanks for advice. I plan to use fabric costume over whole body, except face which I'll paint. Mostly because of typical temperatures in Europe - one or two layers of fabric are better than thin layer of paint on bare skin. In that case hiding LEDs shouldn't be a problem. If this fail, fluorescent dots are my backup option.

I have access to enameled (magnet) wire, few SMD LEDs in 2835 size (about 3x3mm) and soldering gun. Hand soldering for single LED isn't a problem, most of LEDs survive my soldering skills. Just overall number of LEDs to solder looks ridiculously high. My estimations:

• 3 lines of dots per arm
• 3 lines of dots per leg
• 6 lines of dots over front of my torso
• 6 lines of dots on my back.
• Total 24 lines of dots.
• Each line are about 1m long.
• Each line contain about 60 glowing dots.
• Total 1500 LEDs to solder and about 100m of wire (including spare wire for extra elasticity).

What do You think about that size and total number of glowing dots?

I plan to connect all 60 LEDs in line parallel without extra resistors. Not very clever but should do the job for low current. Each line should have current source set between 15mA (0.2mA/LED, night mode) and 300mA (5mA/LED, day mode). IMHO single 10 ohm resistor per each line and one or two variable voltage source (3-6V step-down dc/dc converter) for whole costume should do the job. Add 12V lithium pack and looks like complete solution.

Now I need to purchase zentai suit and start testing.

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Thanks for keeping eye on my project. You motivate me to finish this.

As my first estimates, Na'vi have about 60 slots over leg (single line) plus few more over foot. My leg (excluding foot) have exactly 1m hence scale. As You may see each dot have different brightness and few slots have zero brightness. That may save few LEDs but not many. Arms are much shorter than legs but have higher density. Let say about 50 LEDs excluding hand, 60 including. Same with torso - shorter but even higher density. Need to watch Av i HD and count dots again...
Answering to Toliman's question: I don't like the idea of solder that much LEDs but looks like I have to use at least 1000 LED for full blue costume. Maybe I should cosplay as Avatar driver? No LEDs on torso, just arms and legs :-\

Thanks again. This time I know what I'm doing. I know that voltage phenomenon and I'll try to abuse it . If I connect all LEDs in semi parallel (wires between each should act as small resistors) and apply supply current on each end (+ on first end, - and second) I may achieve ugly effect - each LED have different brightness. That's what I want to achieve, as irregular as Na'vi bioluminescent dots.

That's one of problems that need to be solved later. I like PWM too but that technique wasn't very photogenic. Camera can catch flickering even when eye cannot . Constant current will be better, just need to figure the right way to do that. Also DC/DC converter may be required to adept variable supply voltage (as battery discharges) to almost constant LEDs voltage.


I never seen ethernet cable with stranded wire. I mean bare wire to purchase by meters. Patch cables with stranded wires are standard here, but purchasing them to salvage wires are bad idea.
I can purchase [desc=0.113mm diameter, 0.01mm^2 cross section]AWG37[/desc] magnet wire at local store. That wire are designed to withstand only 155*C (easy to solder through enamel layer) and fold that wire few times to achieve durability. On the other hand I can purchase [desc=0.255mm diameter, 0.05mm^2 cross section]AWG30[/desc] single wires with stranded core but coated with silicone (sticky) or teflone (hard to remove before soldering). Future tests needed.



But first I need to purchase zentai lycra suit. Poland stores offer me standard blue suit while Chinese for the same price can make custom fit one with few extra options like separate toes and detachable hand gloves. Waiting for replay from china, can they make tail for me.



Also new found, LEDs under lycra:





https://www.youtube.com/watch?v=LxMiDvhkTXs
Overall effect looks great. Hope I can achieve similar effect. Ofc. I'll chose regular white LEDs, not the magic RGB, cost does matter. For 10$ I can purchase: 100 pcs Chinese WS2812 or 400 pcs white SMD 2835 from local store or 1000 pcs white SMD 2835 from china.