Hello...my name is Bruce Wegmann, and I live in San Diego, California.
I became entranced with lasers in mid-junior-high school (1965), and the idea of making 3-dimensional pictures was mesmerizing. Through a friend, I fell under the patient mentorship of Keith Bromley and Mike Monahan, who were engaged in optical research at the local Naval Electronics Laboratory (NEL) here in San Diego. They were willing to share all of their techniques and tricks (which allowed me to bypass most of the trial-and-error that would have cost a bundle otherwise...plates were about $2.50 each back then...this was late 1968), and gave me a copy of their Holography Manual, which was a godsend, bearing in mind that, at the time, accessible and understandable literature on the subject was virtually non-existent (I would love to find another copy of it!). For the first time, I got to see really powerful lasers in operation (they had a Spectra-Physics 125 He-Ne and a Model 140 Argon...3 watts!). I got remarkably good results in just a few tries...so good that I eventually made several trips, picking up more of their expertise each time. I still have a box of about 20 of those early 4x5 plates, most of them quite good, even by today's standards (these were all done on silver-halide emulsions, Kodak 649F, if memory serves me correctly...DGC was still a few years in the future at that point). I actually got to putting together a good optical table...a 600-pound granite plate on a reinforced picnic table, supported by inner tubes; a primitive but serviceable replica of the NEL system...and it worked.
I had a unexpected chance to rebuild it on a somewhat larger scale when I went to work for the Fleet Space Theater in 1974 (I was doing laser demos in the Science Center, popping balloons and drilling holes in plastic sheets with a Spectra-Physics 164 5W Argon laser...it was impressive...the first publicly-viewable high-power laser). We set up a 48x60x5 inch granite table (1400 pounds' worth of inertial and thermal stability) in the basement and did some fantastic 5x7 plates (the 164 was equipped with the coherence-extending etalon, giving 800mW of SLM power at either of the principal blue and green lines and capable of an eight-meter image depth...I remember exposure times did not exceed 5 seconds or so).
Over the years, other concerns became of higher priority, and I drifted away from actively pursuing the hobby, but the interest was always there, and the knowledge, though buried, was too. It was sad to see the other forum literally crumble away before my eyes, but it is good to see all the renewed interest in what is really one of the most remarkable developments of the 20th century (surpassed only marginally by what made it possible, the laser itself).
Hopefully, in the months ahead, I will be able to share much what I discovered along the way,
and smooth the path a bit for those just getting started, and who knows, maybe even some of the more seasoned enthusiasts, too...
Introductions
Introductions
Welcome back Bruce! I'd LOVE to find an SP-140 for my collection of vintage lasers. One of the "Holy Grails" of lasers.
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Dinesh
Introductions
We are in San Diego (San Marcos, actually). You're welcome to visit us. We mostly do HOEs these days, but we were actively doing dcg and we occasionally still shoot some dcg if we have any plates to spare.
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Steven
Introductions
Hi, I'm Steven. I'm located in Cornwall UK.
I'm an armature holographer, returning to the hobby after retirement.
I became interested in holography many years before getting my hands on a laser.
I got my first laser in about 1983 or so, and made holograms using Agfa 8E75HD material.
I remember being impressed (Wow!) with my first transmission hologram that I made with an ex-surplus 2mW HeNe.
In about 1987, I upgraded to a 5mW tube, but results were never as good as that obtained using my cheap 2mW HeNe.
I believe the 5mW laser was mode hopping and this proved to be the case after I did some checks.
With the availability of cheap diode lasers and time, I have taken up the hobby again.
I recently acquired a Coherent Compass 315M-100, so my main interests are with DCG.
I still have some of the Agfa 8E75HD material and a few suitable red laser diodes, so I haven't quite given up on AgX
I'm ok with electronics, so I have made, and will continue to make odd bits of kit to further my hobby.
I have plenty of time to experiment with different formulations of DCG, but will start off simple with dip-n-shoot SBR.
I don't have a proper optical table, just a sheet of 1cm scrap steel (40cm x 80cm) sitting on a couple of inner tubes, which is fine for SBR.
I'm an armature holographer, returning to the hobby after retirement.
I became interested in holography many years before getting my hands on a laser.
I got my first laser in about 1983 or so, and made holograms using Agfa 8E75HD material.
I remember being impressed (Wow!) with my first transmission hologram that I made with an ex-surplus 2mW HeNe.
In about 1987, I upgraded to a 5mW tube, but results were never as good as that obtained using my cheap 2mW HeNe.
I believe the 5mW laser was mode hopping and this proved to be the case after I did some checks.
With the availability of cheap diode lasers and time, I have taken up the hobby again.
I recently acquired a Coherent Compass 315M-100, so my main interests are with DCG.
I still have some of the Agfa 8E75HD material and a few suitable red laser diodes, so I haven't quite given up on AgX
I'm ok with electronics, so I have made, and will continue to make odd bits of kit to further my hobby.
I have plenty of time to experiment with different formulations of DCG, but will start off simple with dip-n-shoot SBR.
I don't have a proper optical table, just a sheet of 1cm scrap steel (40cm x 80cm) sitting on a couple of inner tubes, which is fine for SBR.
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dopplerjeff5000
Introductions
Hello everyone,
I'm Jeff, currently a grad. student living in NC. I loved looking at holograms as a kid and then spent a lot of time making them in college at Saginaw Valley State University, where they have a great Optical Physics program heavily influenced by Emmett Leith.
I'm hoping to start up with holography again as a hobbyist after school is over.
I'm Jeff, currently a grad. student living in NC. I loved looking at holograms as a kid and then spent a lot of time making them in college at Saginaw Valley State University, where they have a great Optical Physics program heavily influenced by Emmett Leith.
I'm hoping to start up with holography again as a hobbyist after school is over.
Introductions
So, what's your field of study, and are you pursuing a masters or doctoral degree?dopplerjeff5000 wrote:Hello everyone,
I'm Jeff, currently a grad. student living in NC. I loved looking at holograms as a kid and then spent a lot of time making them in college at Saginaw Valley State University, where they have a great Optical Physics program heavily influenced by Emmett Leith.
I'm hoping to start up with holography again as a hobbyist after school is over.
World's worst holographer
Introductions
Welcome! When you need lasers Sam and I have some...
best! Phil
best! PhilRe: Introductions
Hi. I'm Jon (no "h"). I was a member of this forum quite a while ago, but I apparently got dropped at some point. I've just re-registered.
I made some transmission holograms when I was a grad student, several decades back, using a regular HeNe. A decade or two later I got lucky and acquired a Teletrac ( http://www.repairfaq.org/sam/laserpic/tahnpics.htm#tt1 ) at a surplus place; I made some transmission holograms with it when I lived on the Sammamish plateau, outside of Seattle. The basement floor there was so steady that I didn't need to do any stabilization -- I just put a piece of chipboard down on the carpet, put a wooden frame on it, and set things up on that, using "blu-tak" to hold them in place. I sat right next to the setup when I made the exposures; just made sure I was breathing the other way, and waited for about a minute after the furnace turned off, to give the air currents in the room a chance to calm down.
[[I later got confirmation of the stability of the ground in that area: one evening when we were off the plateau, at a supermarket down in town, there was a magnitude 4.8 earthquake. They threw everyone out, so we went to the supermarket up on the plateau to do our shopping, ...and had to tell people that there had been a quake -- none of them had felt a thing! I really miss that floor.]]
I've been on the east coast for some time now, and after not doing any holography for quite a while I decided a couple years back that I wanted to try again. The basement floor in my current place, however, is a bit of a roller coaster, and I struggled for quite a while trying to make a nice cheap easy platform that's even moderately stable. I finally got somewhere with it about 2 weeks ago, and I made my first reflection hologram on 24 Feb, 2015, on a PFG-03M plate from Integraf, using a fairly high-power violet laser diode (from an SL06 sled, IIRC) that I got from dtr-lpf on eBay a while back. (I had tried to make reflection holograms with the Teletrac, but the plates I was using at that time had insufficient resolution, and I didn't get much.) This was an entirely different experience: the first plate just worked, right off the bat. Mind you, it isn't much of a hologram; but you get to crawl before you walk.
I've been looking into stabilizing the diode to SLM so I can make transmission holograms with it, but that isn't being easy. For one thing, I want it to be entirely passive. That tends to be flaky, but I only need a few seconds for a 63mm x 63mm PFG-03M plate, so if I can get it to stay in lock for perhaps 10 or 15 seconds at a time I should be okay.
I've been writing up this effort; the page with photos of the hologram is at http://www.jonsinger.org/research/broad ... e005c.html if you want to see it.
Best wishes --
jon
PS: I can't find a "Post an entry" button, only "Post a reply". I don't want to reply to one of the existing postings, I want to post a new entry in the topic. (If "Post a reply" actually means "Post a new entry", how _do_ you reply to a specific posting?? This is very confusing.)
I made some transmission holograms when I was a grad student, several decades back, using a regular HeNe. A decade or two later I got lucky and acquired a Teletrac ( http://www.repairfaq.org/sam/laserpic/tahnpics.htm#tt1 ) at a surplus place; I made some transmission holograms with it when I lived on the Sammamish plateau, outside of Seattle. The basement floor there was so steady that I didn't need to do any stabilization -- I just put a piece of chipboard down on the carpet, put a wooden frame on it, and set things up on that, using "blu-tak" to hold them in place. I sat right next to the setup when I made the exposures; just made sure I was breathing the other way, and waited for about a minute after the furnace turned off, to give the air currents in the room a chance to calm down.
[[I later got confirmation of the stability of the ground in that area: one evening when we were off the plateau, at a supermarket down in town, there was a magnitude 4.8 earthquake. They threw everyone out, so we went to the supermarket up on the plateau to do our shopping, ...and had to tell people that there had been a quake -- none of them had felt a thing! I really miss that floor.]]
I've been on the east coast for some time now, and after not doing any holography for quite a while I decided a couple years back that I wanted to try again. The basement floor in my current place, however, is a bit of a roller coaster, and I struggled for quite a while trying to make a nice cheap easy platform that's even moderately stable. I finally got somewhere with it about 2 weeks ago, and I made my first reflection hologram on 24 Feb, 2015, on a PFG-03M plate from Integraf, using a fairly high-power violet laser diode (from an SL06 sled, IIRC) that I got from dtr-lpf on eBay a while back. (I had tried to make reflection holograms with the Teletrac, but the plates I was using at that time had insufficient resolution, and I didn't get much.) This was an entirely different experience: the first plate just worked, right off the bat. Mind you, it isn't much of a hologram; but you get to crawl before you walk.
I've been looking into stabilizing the diode to SLM so I can make transmission holograms with it, but that isn't being easy. For one thing, I want it to be entirely passive. That tends to be flaky, but I only need a few seconds for a 63mm x 63mm PFG-03M plate, so if I can get it to stay in lock for perhaps 10 or 15 seconds at a time I should be okay.
I've been writing up this effort; the page with photos of the hologram is at http://www.jonsinger.org/research/broad ... e005c.html if you want to see it.
Best wishes --
jon
PS: I can't find a "Post an entry" button, only "Post a reply". I don't want to reply to one of the existing postings, I want to post a new entry in the topic. (If "Post a reply" actually means "Post a new entry", how _do_ you reply to a specific posting?? This is very confusing.)
Re: Introductions
Welcome back, Jon.
Your experiments with 405 nm diode are interesting - first, that the coherence of such a diode is sufficient for a hologram, and second, that you are able to reconstruct it.
To the first point: I did not try to make a hologram with a 405 nm diode, but I tried to see its fringes in a Michelson interferometer without success.
To the second point: I am struggling now with a 488 nm laser, because it seems most light sources have a gap around cyan color. It seems you are luckier with 405 nm.
What about scattering? I would expect PFG-03M developed with JD-4 to scatter blue light; did you encounter it?
By the way, I use "Quote" feature in the "post" window if I want to highlight a part of other message.
Petr
Your experiments with 405 nm diode are interesting - first, that the coherence of such a diode is sufficient for a hologram, and second, that you are able to reconstruct it.
To the first point: I did not try to make a hologram with a 405 nm diode, but I tried to see its fringes in a Michelson interferometer without success.
To the second point: I am struggling now with a 488 nm laser, because it seems most light sources have a gap around cyan color. It seems you are luckier with 405 nm.
What about scattering? I would expect PFG-03M developed with JD-4 to scatter blue light; did you encounter it?
By the way, I use "Quote" feature in the "post" window if I want to highlight a part of other message.
Petr