“Relax Honey! We don’t need to call the police! Its just that crazy flashlight guy on the other side, testing out his latest ISS signaling device creation. Just like the other time, we will hear all about it in a few days on the NASA channel.”
What happened to the die projection? Did you burn a part of the phosphor?! 
Waiting for that to come ………… Djozz Van Helsing :smiling_imp:
Agro already noticed the fun detail, although he did not guess it right. 
Are you going to project the legendary ‘bat signal’ with this flashlight? Or better a ‘BLF signal’? 
I could have a try on the bat signal, but it must be cut out of a strip of metal within a 10x10mm area 
The starfish (zeester)?
I know, djozz, you will be playing Nightcore’s Vincent “Starry, starry night” while pulsing the star to the rhythm.
Good work. 
This is how the star is made.
Because I built in some tolerance, the die is focused at infinity when the slider is still 12mm short of the backside.
So when the slider is fully retracted, the focal plane of the lens is 12mm in front of the led, and the die projection is out of focus, creating a fuzzy larger spot instead of the smaller sharp square of the focused die.
So I positioned a cutout of a star (made from the lid of a coffee tin) 12mm in front of the led, which is sharply imaged at infinity by the lens, and because the led is only little out of focus, the throw is still not completely ruined (although I think it went down from 4Mcd to just 1Mcd).
Of course for maximum performance of the lamp, the cutout must be rotated out of the way.
If I find the patience I may have a go at a batman cutout, but it must be tiny, and the metal is tough.
The big optics invite woodworking over metal work (too heavy, too much expensive material), so these lenses are right in your league 
That’s really clever. i like how you added some styling to round off the sharp corners and edges. What about the notches on the side pieces—do they hold something or just a design feature?
i would guess that the fan has an internal circuit board for pwm of the motor current and LV dropout.
Somebody with 3d printing could make plastic masks to shape the beam. But maybe they would melt…!?
That remark inspires me. I once tried to find the techniques involved in making those sixties psychedelic liquid slides. I did not quite find out the fine details but I did find a person (in Zaandam I believe) who was the expert at the time, and he was not dead yet. I may have to contact him after all :cowboy_hat_face:
You know you can do it. I’d suggest a beer to the student that makes the best batman stencil. 
I’d love to do the also MD but you know as well as I do it wood never work. 
What/who was your source?
you can harvest big lenses from old projection TVs at the thrift store and cut them down to size, and people will nearly pay you to come haul them out of their house.
The liquid light film slides can be made mixing insoluble liquids such as water and oil with color tints of either paint type between two panes of glass. Another example is to use air to blow a drop of water across some fresh oil-based paint and enjoy the patterns that develop. Fun stuff to do on drugs…
I bought it a few years ago actually, on aliexpress. They are cheap (under 10 dollar for a 20cm diameter lens) and pretty good, here is a link, I expect it to be the same quality as the ones I got. I chose 200mm focal length as a compromise between the amount of light catched by the lens, and image quality (a very short focal length lens will catch/transmit a large percentage of the light but also show a lot of image distortion at the edges which will negatively affect the beam and throw).
Thanks.
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That is amazing, very well done djozz :+1:
Now that is thinking outside the box ! I never thought a Fresnel lens could do that !
You could do a Batman thingy in the clouds too.
No doubt this years competition is heating up :smiling_imp:
BLF has other forums beat easily
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