Edge lit DCG
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Dinesh
Edge lit DCG
This is an edge lit DCG from a silver H1. The lighting is from an LED housed in a wooden frame at the top of the hologram. I put a tissue in front of the hologram and got no light leakage. In other words, all the light is inside the glass, as opposed to coming in at a very steep angle, which would not be a true edge lit.
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Edge lit DCG
Interesting. Do you use a lens system to launch the laser/LED into the glass?
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Dinesh
Edge lit DCG
The laser, yes. The LED, no. This is why there's blurring at the edges of the image, the reference was distributed along the entire edge of the glass, but the reconstruction light is just a point source in the middle of the edge.
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kyodai
Edge lit DCG
What is the advantage of this besides not having unwanted reflections from the light source? For me as a beginner it is hard to understand why it should be important if something is "truly edge lit" or if no light escapes from the front (Well obviously some light escapes i think or it would not be visible to the eye??). Is this just a fancy displaying method or is there more about it?
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Dinesh
Edge lit DCG
The main advantage is that you don't need an external lighting source. The light is neatly packed at the edge and can be hidden, as I've done (not very well!). So, if, for example, you want to display a hologram in the middle of the floor of a convention hall, they may not allow lights hanging from the roof or have lights nearby. In this case, you can place the hologram on a pedestal, edge light it and it will be completely independent of any external lighting.
Another application: I was asked to design a lighting for a hologram show by an artist (Mitch, if any of you know or remember her). In the show, the holograms were going to be of women's faces and hair displayed in a dark room. The idea was to show the way women sometimes have hidden anxieties that they don't allow the outside world to see. At least that's the way Mitch described it to me (the most extreme opposite of an artist that you can imagine!). So it was important that there should be no lighting at all, the room had to be very, very dark, except for the light of the holographic images. How to show holograms in a room that was completely dark? My solution was to have edge lighting on the edges of the hologram and then hide the lighting by a tape or something. This was 1989 and I had not yet seen the work on edge lighting at MIT. As it turned out, it was difficult for the two of us to make edge-lit holograms in Mitch's basement sand table, so she had to settle for external lighting from the roof of the building.
Another application: I was asked to design a lighting for a hologram show by an artist (Mitch, if any of you know or remember her). In the show, the holograms were going to be of women's faces and hair displayed in a dark room. The idea was to show the way women sometimes have hidden anxieties that they don't allow the outside world to see. At least that's the way Mitch described it to me (the most extreme opposite of an artist that you can imagine!). So it was important that there should be no lighting at all, the room had to be very, very dark, except for the light of the holographic images. How to show holograms in a room that was completely dark? My solution was to have edge lighting on the edges of the hologram and then hide the lighting by a tape or something. This was 1989 and I had not yet seen the work on edge lighting at MIT. As it turned out, it was difficult for the two of us to make edge-lit holograms in Mitch's basement sand table, so she had to settle for external lighting from the roof of the building.
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kyodai
Edge lit DCG
Very interesting, thanks for explaining. =)
Wow you worked with holograms already in 1989? I was eleven years old back then. But i already loved holograms back then. I'm really jealous on so much experience. For me as a total beginner the most annoying things are that the lasers, lenses and optical things are so expensive and that you have to learn so much by yourself or trail and error. For stuff like photography you can take courses everywhere, find a dozen people in the neighbourhood that already do it since ages and can show you a few tricks. I am grateful to have been able to join this forum to listen to pros like you, i have already learned a lot i feel (Like 1% of the whole topic but thats already a lot i guess, haha). Thanks to you for taking the time to help and explain stuff for beginners. It means a lot to me and i am sure there are others that think so as well.
Wow you worked with holograms already in 1989? I was eleven years old back then. But i already loved holograms back then. I'm really jealous on so much experience. For me as a total beginner the most annoying things are that the lasers, lenses and optical things are so expensive and that you have to learn so much by yourself or trail and error. For stuff like photography you can take courses everywhere, find a dozen people in the neighbourhood that already do it since ages and can show you a few tricks. I am grateful to have been able to join this forum to listen to pros like you, i have already learned a lot i feel (Like 1% of the whole topic but thats already a lot i guess, haha). Thanks to you for taking the time to help and explain stuff for beginners. It means a lot to me and i am sure there are others that think so as well.
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Jeffrey Weil
Edge lit DCG
Hello Dinesh,
Mitch was great, lots of fun. Do you know where she is now?
No one had an easy time with the edge lit method. I saw all the MIT stuff back then in the 80's too. Only that one hand held version of "Breakfast attempt" was good enough to be called a real product. It was a pretty good stereogram of a diner like table with breakfast foods on it.
I saw only one copy at that level of quality.
Dinesh, what's the best edge lit holo you've seen?
Jeff
Mitch was great, lots of fun. Do you know where she is now?
No one had an easy time with the edge lit method. I saw all the MIT stuff back then in the 80's too. Only that one hand held version of "Breakfast attempt" was good enough to be called a real product. It was a pretty good stereogram of a diner like table with breakfast foods on it.
I saw only one copy at that level of quality.
Dinesh, what's the best edge lit holo you've seen?
Jeff
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Dinesh
Edge lit DCG
Hello Jeff
The last I heard Mitch was teaching snowboarding in Vermont. I believe that Augie is still in contact with her. I think I have his contact info, if you want. I always had great fun with Mitch and she was very creative and spontaneous. I remember when I was at her house in Rhode Island looking at a hologram under fluorescent light and seeing zip; well, almost zip. She asked why you couldn't see a holo under fluorescent lights and I explained that it was made with a "point source", ie the laser is a very small source point. Well, we were both silent for a while, then we both blurted out, "So, if you actually referenced it with a fluorescent light, you'd be able to see it in fluorescent light, right?" This was at about 8pm. We spent the next hour getting a rod and rubbing it with sandpaper to simulate a cylindrical, rough surface - a fluorescent lightbulb. We then went down to her sand table, spent an hour launching the light into the end of our makeshift "fluorescent laser light bulb" and another hour finding a way to reference the light coming off the sides onto a plate. Finally, about 3am, we got a hologram, rushed up to her kitchen and LO! A clear hologram under fluorescent lights!
Later she came to LA so we could drive up to San Jose for SPIE. She wanted to come in early, so we could spend a day or so visiting all the holographers in Northern California. That's when I first met Bob and Jeff Murray. I think it was Jeff who told us we had to see the "Blow Job" which was somewhere in San Fran and jealously guarded by someone who didn't realise the 60's were over. Mitch took it on as a holy mission to see the "Blow Job", but sadly we never managed it. I still haven't seen this apparently mythical hologram!
Best edge lit? Unfortunately, I have to say: mine! I never saw this "Breakfast attempt" you mention. Ryder was the edge-lit guy at MIT. I remember he was miserable during the Austria convention in 2000 because he was supposed to present his work on edge lit and show his work. He told us he could never manage to make a good one. I've since heard this from several of the "Benton Boys" (Yes, I know that Mitch and Mary-Lou were "Benton Boys" - I still call em that, though!).
Personally, I think that it's the dcg that does the trick. I've also tried several attempts at edge lit in silver and got nowhere.
The last I heard Mitch was teaching snowboarding in Vermont. I believe that Augie is still in contact with her. I think I have his contact info, if you want. I always had great fun with Mitch and she was very creative and spontaneous. I remember when I was at her house in Rhode Island looking at a hologram under fluorescent light and seeing zip; well, almost zip. She asked why you couldn't see a holo under fluorescent lights and I explained that it was made with a "point source", ie the laser is a very small source point. Well, we were both silent for a while, then we both blurted out, "So, if you actually referenced it with a fluorescent light, you'd be able to see it in fluorescent light, right?" This was at about 8pm. We spent the next hour getting a rod and rubbing it with sandpaper to simulate a cylindrical, rough surface - a fluorescent lightbulb. We then went down to her sand table, spent an hour launching the light into the end of our makeshift "fluorescent laser light bulb" and another hour finding a way to reference the light coming off the sides onto a plate. Finally, about 3am, we got a hologram, rushed up to her kitchen and LO! A clear hologram under fluorescent lights!
Later she came to LA so we could drive up to San Jose for SPIE. She wanted to come in early, so we could spend a day or so visiting all the holographers in Northern California. That's when I first met Bob and Jeff Murray. I think it was Jeff who told us we had to see the "Blow Job" which was somewhere in San Fran and jealously guarded by someone who didn't realise the 60's were over. Mitch took it on as a holy mission to see the "Blow Job", but sadly we never managed it. I still haven't seen this apparently mythical hologram!
Best edge lit? Unfortunately, I have to say: mine! I never saw this "Breakfast attempt" you mention. Ryder was the edge-lit guy at MIT. I remember he was miserable during the Austria convention in 2000 because he was supposed to present his work on edge lit and show his work. He told us he could never manage to make a good one. I've since heard this from several of the "Benton Boys" (Yes, I know that Mitch and Mary-Lou were "Benton Boys" - I still call em that, though!).
Personally, I think that it's the dcg that does the trick. I've also tried several attempts at edge lit in silver and got nowhere.
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Jeffrey Weil
Edge lit DCG
Hey Dinesh,
Breakfast attempt was silver too. It looked pretty good. A little bit noisy but nothing a client would really mind. I think it was on a piece of plastic about 7mm thick and it was tall. I think the plastic was about twice as tall as the holo mounted to it. Light at the bottom, holo at the top. More room for the light to spread of course. Would that be cheating?
When I met Mitch we went snowboarding, it was her first time. It was my first time seeing snow. This was in Tahoe after San Jose. The snow that weekend broke a 20 year record. Do you have any idea how hard it is to put chains on your tires, in the dark, in the snow, on a mountain, when you've never even seen chains before?
I bet we met somewhere before Prague. All those symposiums in the 80's and 90's. We were at a few together I bet. Plus you knew all the MIT'ers back then, so did I. At San Jose we all shared a room before snowboarding.
We must have met somewhere before holopack in Prague, or was it Budapest where we first met up? What I remember most was our debate with Gunther Dausman and that guy from BASF that did the explosive holographic embossing. What a great techi debate that was.
Jeff
Breakfast attempt was silver too. It looked pretty good. A little bit noisy but nothing a client would really mind. I think it was on a piece of plastic about 7mm thick and it was tall. I think the plastic was about twice as tall as the holo mounted to it. Light at the bottom, holo at the top. More room for the light to spread of course. Would that be cheating?
When I met Mitch we went snowboarding, it was her first time. It was my first time seeing snow. This was in Tahoe after San Jose. The snow that weekend broke a 20 year record. Do you have any idea how hard it is to put chains on your tires, in the dark, in the snow, on a mountain, when you've never even seen chains before?
I bet we met somewhere before Prague. All those symposiums in the 80's and 90's. We were at a few together I bet. Plus you knew all the MIT'ers back then, so did I. At San Jose we all shared a room before snowboarding.
We must have met somewhere before holopack in Prague, or was it Budapest where we first met up? What I remember most was our debate with Gunther Dausman and that guy from BASF that did the explosive holographic embossing. What a great techi debate that was.
Jeff
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Dinesh
Edge lit DCG
Now you mention it, I do remember the guy with the explosive holographic embossing! Later that evening at the bar, I asked him what explosive he used . He wouldn't say!Jeffrey Weil wrote:What I remember most was our debate with Gunther Dausman and that guy from BASF that did the explosive holographic embossing. What a great techi debate that was.
I also remember Gunther. No matter what you said, he had a patent on it!