Holography Demonstration

[xenodrone]

so the guy who is a master of the theremin is also a master of holography?

well, I'm impressed..

[ThomasGrillo]

@xenodrone Indeed. Thanks. :)

[Hyrobaka]

now you need to figure out how to manipulate a hologram with the music from a theremin, so that it can be dynamic and flow in infinite combinations of object and color, perhaps even recognizable moving shapes, like people dancing....

[ThomasGrillo]

@Hyrobaka COOL! Although this won't work with real holograms, a theremin's audio output could be routed into a computer to control a CGI 3-D animation on the fly. Morphing of shape could be handled by pitch, while color could be controlled by the volume dynamics. This would indeed be a fascinating exhibit for museums, and art galleries.

Thanks for the idea! :)

[AsaphProject]

@Hyrobaka That may be the greatest idea I've ever heard!

[sabaths1fan]

awesome

[ThomasGrillo]

@sabaths1fan Thanks. :)

[ThomasGrillo]

Ruffie2 posted this question which was accidentally deleted. Sorry.

Is it normal when the beam becomes

like little spots everywhere when it goes

through a lens? Or am i going the bad

direction when that happens?

[ThomasGrillo]

@Ruttie2 When directing a beam through lens without a spacial filter, you will see dark spots or swirls within the expanded beam. This is caused by dust on the lens. Spacial filters clean it up.

If on the other hand, you mean the tiny little speckles that resemble film grain, this is just a function of our own eye's cells as they are receiving only one frequency of light.

[Ruttie2]

@ThomasGrillo I see, but it can't be dust

because i cleaned it yesterday. It lights

up well, but the light (on the wall for example)

only shows hundreds of small spots, like

stars, i tried other methods to spread the

beam, but i ends up the same way... Is

this how it's supposed to be?

[ThomasGrillo]

@Ruttie2 It's possible your laser is contaminated with dust, but not likely. Without a spacial filter, you will see swirls, and spots all the time. Spacial filters work differently. they use a disc with a pinhole and a spreading lens to filter out that noise. No matter how well we try to clean our optics, there's always dust settling on the lenses, and mirrors all the time. I highly recommend spacial filters. They are the way to go if you want good gousian beam spreading.

[Ruttie2]

@ThomasGrillo Oh ok, so i have to get

a spacial filter. I knew there was something

wrong! Thanks man!

[ThomasGrillo]

@Ruttie2 You're welcome. You can find spatial filters at Newport on the web. Be warned they're not cheap. Back in the 90s, I paid about $800 for just one. And that was the cheaper model. But if you're going pro, it's well worth every penny, and the effort it takes to set up spatial filters.

[Ruttie2]

@ThomasGrillo Oh ok, so i need a

spacial filter right? Oh, and i had one

more question. There's this stuff going

on on the internet, which claims you

can use a digital camera to create a

holographic motion picture, and then

reconstruct it by using an LCD as a

heat pattern or somethin' and light

it up with a laser.. Is that stuff for real?

[ThomasGrillo]

@Ruttie2 In holography, you can use an LCD display as the source for motion picture holograms. A playback device off table provides the frames of video to be imaged one by one. The laser lights up the LCD display using a diffuser behind it. The display is treated as any object in a holo lay out for transmission holography. The LCD's images are focosed on to the film plate as a slit. Dozens of slit holograms are made one by one. The reference beam is set up for transmission holos.

[ThomasGrillo]

@ThomasGrillo Oh, getting back to spatial filtering, there is low cost, low tech approach you can use which involves not using a lens, but instead, bouncing the beam of the dull side of a bit of aluminum foil, or by shining the beam through a diffuser, a bit of frosted glass or plastic. It will produce a nice gausian spread, but will be much dimmer than with a filter. If your laser is at least 5 mW, or better yet, 40 mW, you should be ok, but exposures will be way longer.

[sirbooner]

That is so awesome!

[ThomasGrillo]

@sirbooner Thanks. :)

[etiennealive]

A question ; Is it possible to create a holographic image, without using an object. Instead a drawing made in autocad, combined with software to control the laser etching proces ? If it is possible it could open new doors in research.

(It's a serious question)

[ThomasGrillo]

@etiennealive Making holograms does not involv steering a single beam around, but rather, spreading beams of light to bounce off objects. Holographers have indeed used CAD 3D models which were played back on a transparent LCD through which laser light was passed as if the LCD were an object to produce holos. Consult wiki regarding animated holography for more on this. See also holography Handbook, and Practical Holography for more.

[etiennealive]

@ThomasGrillo Thanks for your reply.

[ThomasGrillo]

@etiennealive You're welcome. :)

[etiennealive]

Very interesting, thanks !

[ThomasGrillo]

@etiennealive You're welcome. :)

[TherapudicCaffeine]

This is really cool, but it looks like it was recorded with a home camcorder from 1974. :P

[ThomasGrillo]

@TherapudicCaffeine It was recorded in the mid 90s on a camcorder that dates back to the mid 80s, an RCA Small Wonder VHS camcorder. Tops in it's day, but rubbish today. ;/

[sk8lakemount]

really cool and interesting explanation its really awesome that you respond to everyone

[ThomasGrillo]

Thanks. It's what I do. :)

[beefknuckles]

I found this video from random youtube hopping and found it very interesting. Your explanation was really easy to understand. Thanks for putting this up.

[ThomasGrillo]

You're welcome, and thanks for the kind words. :)

[SHADOSTRYKR]

I was waiting for princess leia to pop up and say " help me obi wan kenobi, you're my only hope"

[ThomasGrillo]

Nah, not for quite some time yet. :)

[MrFixErit]

Thanks for the informative video. Could you do an update with the anomaly of "the whole is contained within the part" of the interference patterns? Possibly has some relation to the otoacoustic emissions and the theory of Holophonics. Id be keen to see your interpretation on the theory thanks and well done.

[ThomasGrillo]

Perhaps someday I may do another video which would go more deeply into the theory of holography. It may be some time though. At the moment, I'm extremely busy producing music with the theremin. :)

[CodfishCatfish]

An awesome video. I just watched a similar video on the Discovery channel here in the UK (How it's made) and I went looking for answers. Thanks for the upload. I want to make my own holograms and wondered if it was possible to get around the 2 tonne table with a floating air bed (like an air hocky table). Great stuff thanks again

[ThomasGrillo]

You're welcome. :)

Holography requires a mechanicaly, and accoustically stable environment in order to work.

This means a solid, stable mass of sufficient density, isolated from ground vibration. The set up I had was over-engineered. Turns out I could've got by with just a 1 or 2 inch thick by 4 x 4 mass of concrete paver stones (four 1'x1'x1') layed on carpet, particle board, more carpet, 4 inner tubes, more carpet, particle board, more carpet, 5 concrete blocks for legs.

[Deathscythetransform]

all that stuff must cost a lot!

[ThomasGrillo]

It did. Now, it's nearly worthless doorstops. LOL :)

[Deathscythetransform]

thats what they call evolution of technology

[ThomasGrillo]

Indeed. :)

[cosmogang]

You still in MS?

[ThomasGrillo]

Yeh, just not where I was before. :)

[cosmogang]

I'm from Hattiesburg. Dude, I gotta say. This is some werd stuff.

[ThomasGrillo]

Cool! :) I hear y'all got more snow than we did.

[cosmogang]

Are you real?

[ThomasGrillo]

As far as I know. I thunk, therefore, I compute.

[rurikvred]

posted in 2007, no new updates must mean you're on contract and have something fantastic you can't reveal. Yes?

[ThomasGrillo]

That information is compartmentalized at this time.

[chrisvogel88]

hahaha..are u up @ 3:30 in tha morning?!?!?! lol...tru scientist!!! XD

[ThomasGrillo]

From time to time, I am indeed up at that hour. :)

[tylerama90]

OMG EVEN FASTER

[ThomasGrillo]

LOL, dear, oh dear. :)

[tylerama90]

you reply fast

[ThomasGrillo]

Indeed. It's the polite thing to do. :)

[tylerama90]

@ThomasGrillo omg that was fast

[ThomasGrillo]

Indeed. LOL :)

[ThomasGrillo]

Indeed. Make it so... :)

[MiguelCSuarez]

Incredible stuff! Thomas, you should be asked to make one of those "How its made" programs!

Great work! Thanks!

[ThomasGrillo]

Thanks for the vote of confidence, and you're welcome. :)

[joeythewing]

Lol, you are quite poilte when you respond to everyone.

[ThomasGrillo]

Service with a smile. :)

[jeremywilson15147]

very nice....

[ThomasGrillo]

Thank you. :)

[camiller3754]

O.O that is awesome

[ThomasGrillo]

Thanks. :)

[cwward1]

Interesting topic. Holographer, thereminist, what else do you do?

[ThomasGrillo]

I sing in opera choruses, and enjoy flight simulation, as well as science fiction. :)

[Godsdarkness]

well thats interesting.

[ThomasGrillo]

Thank you. :)

[omersonnosremo]

how can i get that holographic plates??

[ThomasGrillo]

You can get holographic films and plates through Intergraph. They also offer a beginner's intro level kit that includes some chemicals, a box of small 2 inch plates, a battery powered diode laser, a rubber pad for vibration isolation, trays, and instruction booklet. You can get it online at:

holokits . com.

[omersonnosremo]

thank you very mush for your all contributions i must visit that web site...

[ThomasGrillo]

You're welcome. :)

[JeremyLeroy96]

i wish i knew how to make this

[ThomasGrillo]

I recommend the books Shoebox Holography, Holography handbook, Practical Holography.

Start off with the holography kit at holokits . com, They'll even include a booklet full of instructions.

[vVvEnvyvVv]

Um so this isnt a REAL hologram? you know floating light with nothing there? its a film that a laser shines into???

[ThomasGrillo]

These are indeed real holograms. Holograms are simply a sheet of photographic film, or a photographic glass plate. They have a layer of light sensitive emulsion on them where the hologram is recorded.

The microscopic silver crystals in the emulsion become many tiny mirrors after exposure and processing and reflect light in a way that reconstructs a virtual 3-D scene of the original when laser or white light shines on, or through the hologram.

Check out my Holography Lecture for more info.

[burnoutnt]

Thank you for posting this, I had been looking for something like this for a while now... thanks!

[ThomasGrillo]

You're welcome. :)

[justincase80634]

I remember making a hologram my senior year in HS, way back in 1989. We were the first class of "laser technology".

[ThomasGrillo]

That's about the time I started making holos.

That's awesome that you got to make holos in high school at that time. :)

[justincase80634]

It was awesome! I'm sad that they no longer offer the class, now that my kids are in HS. The resolution was so poor on our holograms, we never could tell what they were.

[ThomasGrillo]

Indeed. I miss the ilford plates. That stuff made the best holos I'd ever seen. So did the Agfa plates and films.

I hear you can still get the green laser type plates from Agfa, and now that green diode lasers are less expensive, that might be a good way to go.

I tried the Russian plates, but was not as satisfied with them as with the older stuff.

[GUNSESES]

woh

[lunazzi]

It is very hard nowadays to obtain holographic film. AGFA, ILFORD, FUJI, stopped production. The only one available is made at Russia, and has little storing period, in less than six months after fabrication, may louse capability.

[ThomasGrillo]

This is true. However, I've learned that Agfa still produces green sensitive films and plates. ;)

Also, there is yet another alternative. Dichromated jelatin holography. You have to make your own emulsion, and spin coat your own plates, or use one of a couple of other methods to coat the plates with.

The other alternative is photopolymer.

[papalocowow]

You can make a hologram, but you can't get a decent videocamera or digital recorder?

[ThomasGrillo]

This vid was made in the early 90s on a 2K$ RCA Small Wonder which was made in the mid 80s.

The video tape was lost for over 10 years. By the time I found it, the tape had nearly oxidized. This is why the quality looks so poor.

I now have high def cameras which I use for my newest videos. Have a look at my channel.

[patatahooligan]

What I don't get is how do you decide how long the exposure of the film is supposed to be.

[ThomasGrillo]

This "was" to have been covered in another episode which never got produced.

Exposures are determined by light meter readings of the reference beam, and object beam(s), as well as the output power of the laser. Much of this is also covered in all of the how to books on holography, like Holography Handbook, Practical Holography, Shoebox Holography, and others, all of which are available on the web at rossbooks.

40 mW hene with 4x5 plate = 1 to 2 sec exposure.

5 mW hene on same=15+ sec.

[whiteakers]

fascinating stuff! thanks very much for the info

[velveticepick]

Your videos look like they're out of the eighties or local access television, but they're all great!

[ThomasGrillo]

...It was. ;)

This was an excerpt from a public access program I did back in the early 90s. As soon as I find an xp machine that can handle AVI files, the rest of that video will go online since I'm a partner now.

Had this been done today, the video would've been much better. ;)

Thanks for the kind words. ;)

[ladymaggic]

I did not realise they were so complicated to create..I will appreciate them even more.

Excellent information..

Thank you

[cazmaj]

Do u think it is possible for hollographic tv suspended in mid air? :P

[ThomasGrillo]

There is a 2-D video display which suposedly projects a mid-air image. But it's incredibly expensive, and the picture is less than impressive. 3-D versions are just not feasible for the near future.

[cazmaj]

Thats very interesting to know! Thanks for the responce :D

[Xiao6996]

Although I have seen some very impressive standing free form even moving holographic imagery with current technology, its very impressive stuff. Although my friends and I are waiting until someone comes up with a hard light projection, heh yeah I know, pretty impossible in our lifetime.

[ThomasGrillo]

That may not be as far off as we once thought. Perhaps in another 20 to 30 years, we might see free floating hard light projections, one never knows these days. There is a cool projection you can do right in your own front yard. Just take a water hose, put a baffle valve on the end that will create a fanned out fine spray of water which becomes a "clear" screen, and point a video projector at the water screen. Boom! You got a free floating projection. Perfect for halloween. Casinos use these.

[Xiao6996]

Perhaps, however I still believe that the cost for maintaining such a "hardlight" holographic projection would probably be unmanagable for most. Not just in mere capital for the sake of keeping it in good repair but also cost to keep running the machines capable of producing a hardlight image. Though it is a lot of fun to fantasize about what sort of things they could do with such technology at hand. I have no doubt we are capable of developing the technology, however the focus is elsewhere.

[baseace777]

finally another REAL holographer WELL DONE

[NeoAvanarb]

man thats awsome

[boutan2004]

DUDE, IM YOUR BIGGEST FAN!! YOU ROCK MAN!!! ROCK ON!!! ha!

[vertex21]

Thomas, do you think that we'll ever have holograms that could be interactive like they have on Star Trek the Next Generation?

[ThomasGrillo]

I don't think it's possible because holograms are just photons reflected by microscopic mirrors in the two dimensional plane of photographic emulsion.

For a holodeck to work, it would have to use resequenced matter from the so called transporter. This is scripted in Trek, only they got it partly off. There, the observer is transported repeatedly to the starting point within the room as they walk within the holodeck. In reality, the transporter would also produce the worlds with real matter.

[Mrnavis]

Nice!

[joeythewing]

cool

[lawdawg430]

again, excellent.

[zilome]

kool

[VonRichter]

Rad.