+Practical Engineering "One of America's seven modern civil engineering wonders" :D. You have to love the pathos and parlance of these old documentaries. Civil engineering is absolutely fascinating, but at the moment I'm confined to the smaller things that I can actually involve myself in :D. BTW: Great to see you here in the comments and to know that you liked the video!

An very interesting type of decoration can be achieved by using multiple layers with some of them moving/spinning...

I didn't think that people would take me literally when I said, that you can toss the other stuff away. I didn't mean that the other parts are totally useless. I meant that you don't need them for the projector.

My hearth just started pumping again.

+Len P What does your hearth pump, oil?

Lennart Nilsen, blood, maybe.

Imposter! Everybody knows that Bielefeld doesn't exist

it serves dual purposes. .. generate electricity. .. and its also a temple dedicated to alcyone .

Any tips for this mod?

i can provide you with pictrues of my builds ( over 25 builds )

I suspect it's technically possible but with an overhead projector you would need powerful lighting, I doubt LEDs would work but you could use a traditional UV lamp that would be compatible with the OHP (this would probably make it cheaper too). You would really need to make sure no light is spilt out for it to work properly and for safety. I don't know if OHPs have UV filters on the glass, I know a digital projector I took apart did (I used a small UV LED keyring to test the elements).

It all depends on the beam characteristics (both of the light source and the projector). As you know, LEDs are much more directional than any of the old style incandescent or halogen bulbs. If the projector is set up internally to harvest as much light from that omnidirectional light source and spread it evenly over the whole projection surface, it may be hard to compensate for the LED that beams its light only in one direction. Other than that, just take care that it's bright enough (cooling will also become an issue), I'd try it with something around the 50 Watt range, but that might actually be too bright already. And of course there's the light color, which will give you just a "whiter" white when you use LEDs in the 5000-6000 Kelvin range, instead of those in the 3500-4000 Kelvin range that resemble the old style bulbs a bit more (they're sold as "warm white"). If you really want to save on energy as well, build a proper "joule thief" circuit for it (with an adjustable potentiometer) and you'll make it much more efficient. For that, having a LED that's a bit too bright is actually good because then you don't need to run it at 100% brightness, but go down to 95% and be even more efficient with a Joule Thief.

I was thinking about this while watching. You'll want LED's that render color well. This store has many options for LED's with up to 98 CRI. Check out some of the youtube reviews for them. store.yujiintl.com/ This is a fun project to watch.

Well, actually LCD panel LED's don't use high CRI LED's. Some use RGB LED's for high gamut, but you'd still have an edge with color.

Awakened Anhedonic Isn't the color calibration of LCD panels usually done through the panel itself, so it can be independet from the LEDs?

Yes, it'd look fine without the perfect light source. There's a lot of people who say plasma screens with fluorescent backlighting had better color. Today screens use cheap LED's. High gamut screens that cover the Adobe RGB color space use RGB LED's which have sharp intense peeks in each primary color. The spectral characteristics of the light source is still relevant, even though LCD filtering compensates.

Displays in tablets (and phones) are almost always glued/laminated together. No chance getting light through them from the back.

Good to know you care about AMERICA!.

It's historical - made in West Germany!

Yeah but still Germany.

darude sandstorm

Ich habe 60 € bezahlt auf Ebay Kleinanzeigen. Wenn man ein bisschen sucht findet man auch schon welche ab 20€ aufwärts.

It adds no delay. It is as "fast" as the monitor was before being added to the projector, because he isn't doing anything to the video signal.

Richard o sick bro

He mentioned it gets "acceptably" hot. If you want to enlarge its life span, cool it even more down ;)

would it not be released as heat?

if you used these in a classroom, you'll know the glass gets fairly warm or to some, untouchable. Several of my teachers would use a glove on their writing hand to avoid burns.

Water cooling monitors anyone? :D

You could try transparent mineral oil xD

Sort of, ive seen someones video where he made artificial windows from broken monitors

Those lights are quite inefficient, not that bright for a room and the high voltage power supply needed are quite a hassle (and dangerous, if you don't know what you're doing). There are conversion kits for many panels that allow you to exchange the high voltage tubes for LEDs. But again, if you want lights, get LEDs made for lighting. (e. g. glue LED strips to a board and just use the diffusor out of the panel)

I don't see why some of the newer white COB LEDs couldn't be used.

+williwonti good idea, I have about 10 laying around so won't cost me anything to try!