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Daguerreotype holography


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Title Daguerreotype holography
Title of Series 7th International Symposium on Display Holography (ISDH 2006)
Part Number 11
Number of Parts 61
Author Miller, Shani
Elliott, Alan
Gouthro, Jessica
Wilksch, Philip
License CC Attribution 3.0 Unported:
You are free to use, adapt and copy, distribute and transmit the work or content in adapted or unchanged form for any legal purpose as long as the work is attributed to the author in the manner specified by the author or licensor.
DOI 10.5446/20997
Publisher River Valley TV
Release Date 2012
Language English

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Subject Area Computer Science
thanks very much in the last thing everybody yes I'm from there are mighty in Milton Australia where as you that briefly before we've been running of holography that for the last 30 years or so actually set up in the mid seventies by Bob Shaw the who likes to see that our mighty when he retired and there in the in the mid seventies in bob but interested in holography and at the same time is a big public appeal for funds that are mighty from which they're liable to buy and that I spectra-physics out online later that's that's where it all started except that the lies was actually donated to the photography department that but I didn't have the space or the expertise to to look after the so the physics it will will will do that takes about will Salazar and will share with you the photographers because of photography was in the US Department and course of physics in the in the science faculty and but that's so the collaboration at that worked out very successfully and has extended over the over all these years and so they've been a lot of collaborative projects between photographers and and scientists and in this talk details 1 of those collaborations so the and
and In the talk of give the background that a brief description of what the daguerreotype prices is for those who are familiar with that which I wasn't until it is predicated on and then some measurements that we did to determine the possibility of the of recording holograms on Daguerrotypes and some of the results of the GUE just to the
a point at which participants were in this project the photography students have to do in a final year project and part of the bachelor of science applied science and scientific photography and shiny that was of the talk every student no previous experience in holography but she was interested in Daguerrotypes as a photographic media so she makes inquiries got on the internet and I spoke to Charlie China who was a holography in the in the series of events in the United States but to find out what possible projects that might be to do with with Daguerrotypes and challenges suggested that maybe the make a hologram with them because now you never tried to beef or and and those are shining what you give go and just as it has another great fortune we had the holography that has poverty is well what you know that when she started out and this year and this also we have an island and get involved and it is a semi retired chemist who was hobbyists and enthusiasts in Daguerrotypes photography and knew all about the processing details which are quite kind and require a lot of experience and and so on so he was that was a major part of the project Jessica you throw it was produced in the physics department so became a collaborative project between students in physics and photography and and I helped with the whole of of the portion of and
associate the idea kind actually this combination from Chinese and Charlie so the
daguerreotype process was actually the very 1st commercial version of photography that became possible that in uh was actually 39 is mistake on this slide it's good begin so they
should be item 13 on it and the hand uh photography processes was invented in the period between authorities in the fifties uh several techniques became available the together talk was the first one to be commercially viable it was superseded in the 18 fifties and by more convenient and less cumbersome technique but is still practised by people who were confused by the quality and the particular characteristics of the the hologram of the sorry the
and it is but is still the highlight process but is quite different to the the ordinary which processing highlight the technique that you start off with a copper plates uh which you then lecture with the silver coating the so it is a highly polished to to give you have a mirror surface so it's just have a good quality still that then that is exposed to hydrogen fuel in various proportions depending on the recipe book you look at that bromine and iodine uh in various proportions and that forms the silver highlight film on the plates and
the and the way in which the uh the coating thickness is judged by the Praat practitioners of this is to look at the color of the thin-film interference and of course is a coding builds up you move through the interference colors and their various recipes for knowing when to stop when you got required thickness then
the plate is exposed um the ends as with ordinary so that highlight photography the action of the life is to reduce some of the silver halide compound to solar metal particles short wavelength light this is necessary in the blue end of the spectrum although the technique is known to have some sensitivity in red the sensitivity increases pretty much was of but even then it's a very slow technique you need minutes typically in dialog with suitable camera for wide aperture to produce reasonable results but during this exposure reduced so the particles are formed within the cell that has a lot like the development is
traditionally with Mercury so the places they killed over a a ball of Mercury which is heated gently to choose mercury fumes and the mercury fumes form silver amalgam with the so the particles and then this then gives you particles of a reasonable size on on the surface of the plant this photo shows an element in its set up for for doing the this this work is idea and of little guest the sitting upon their privacy and the place is filled in the box at the top there and Allen's designs and filters so there's not too much more provide the blind in the atmosphere and its a family and therefore its circulation but there
is an alternative method called a big role take their technique by which doesn't use military so that's an advantage for that it so that it produces less sensitive resulting you gotta have a longer exposure for it to work properly and the they're cruel technique involves covering your plight with my line of of radiant uh Ruby for something similar and exposing it to all of these last for a long time and the action of the of the long-wavelength rise uh somehow accelerates this growth of the silver particles on the place people aren't too sure about the the actual process that goes on and then the plate
is fixed to remove the remaining so unexposed silver halide and rinsed and dried etc. and it can then be for the gold layer over the top of that to protect the year year so the
particles to view the plates watching and have is is a set of of very small find on an album particles on top of under a service so that if you eliminate the plates obliquely and look at that moment students the unexposed portions of the plate will look back because it's reflect light in different directions and exposed portions where you have defined scattering particles will look like and so you see an image incorrect contrast that if you could if you alter the viewing and other viewing conditions you can get reversal contrast you'll see the exposed areas is doc uh relative to the the brighter background of middle of the Bureau surface if you look along the specular reflection direction
but some of the normal way of viewing it gives you a positive result is an example of a traditional Daguerrotypes made by by shiny 1 of the stately homes around the daguerreotype is prized for its very fine resolution find the time very delicate appearance and it's typically naturally laterally reversed because you're exposing the plot of the pinhole relations onto applied which is facing in the opposite direction so thinking about that because you reversed the image that's not transparent model normal transparency but the whole process is quite unpredictable in some ways because it has been so the developed over the individual into the initial technique and there are lots of variables in sensitizer applied and how you prepare process and had to develop so it requires a lot of skill and a lot of experience and a lot of luck but can be useful holography
we know that the resolution of the technique is is is very high the at the grain size of the silver particles is the this mark on could be quite a bit less and so should form applying amplitude hollow-gram the scattering particles should act like the absorbers would only would in in a silver halide emotions and the smooth type background should act like a transparent sections of ordinary playing amplitude hologram in passing a wave wavefront understood but to see just how successful at what work is a hologram and we could make measurements of sensitivity
and resolution so this was the start of the project is what the the physics student got involved in the start that we needed to test the resolution and sensitivity and we did that principally at the 2 wavelengths of 450 item 48 and images of argon ion laser them by setting up
diffraction fringes just 2 been uh system model like this where we introduce 2 being almost the same angle so we can check the sensitivity for fringes with large separation this illustrates the fringes form with some variation in the sensitivity across the plains from parallel in parallel beams 1 side to a very large and the other side or was a
mortar that can equally and common set up here with with 2 beams of physiological so
what we did that ends at the the low and behold yes we did get very nice diffraction gratings on the left-hand image data shows and I a single tied with them in different exposures that around circumference they increasing exposure times and on and on the right-hand side you see a microscopic image of the fringes formed on the surface and so by doing this for a
range of freedom separations and type preparation recipes that we drew a graph of the the diffraction efficiency of those fringes versus the exposure diffraction efficiency Mary Bayesian very simply by shining a little um classifier the multiplied to the and measuring the power in the before and after it applies and when was different from the plates in the diffraction direction the measurements are little bits of noisy of course because of the uh uh the unpredictability the unpredictability of the technique also because some these exposures a rather long and you got expect some fringe drift during these times and but they do indicate that under the best conditions you can get good diffraction efficiencies 3 or 4 % with an exposure between 1 and 2 angels square centimeters and this is for something which we think would not would buy the same rules apply on integers hollow-gram so a financial again your maximum diffraction efficiency around 6 % the ends so 3 % up today so the 1st
attempt to create a rainbow hologram was done at 48 lies that we had been we couldn't get very much power that 459 instead of 4 58 was 458 so tried before I get to start with we did the master recording and conditional uh means to onto the solar highlight master and then just the final transfer onto the rainbow hologram because that gives you lots of advantages you can concentrate a lot nicely in the in in the transfer stage used the maximum light economy and work with a fairly small separation between the angle of your object and reference beams to make sure the fringes out to fight believe in so to get 1 dual persuasive immediately had had an exposure time of 45 minutes and and so now
we did expect exercise stable for that long but we thought well maybe the drifts will average out so we we have some other time with a stable image this shows the results on the left hand side is is a conditional so highlighted um rainbow hologram result show should look like right hand side is what we got and if you look very carefully screened dries bits and you can you can start to see the beginnings of a face in in the middle of the hologram there so that was find but promising and that was back in 2003 in 2003 when we did that but more recently we've managed to get realize after the 1 that we we bought in 1975 we finally got the money to replace 1 that ends up so we tried
again this time we had more power available so we went for 58 nanometers we produce the master hologram with a better efficiency than the previous
1 we arrange the transfer configuration but where we minimize the angle between the the reference beam the the projected image from the master hologram using a cylindrical to to eliminate line on the mass of the grand and we managed to other than
that is a picture of set of we
managed to reduce the exposure times down to less than 15 minutes will to 15 minutes with rituals disgrace uh do trials of farmers 4 . 7 jewelled disgrace and this report perhaps that is why I think will have more sensitivity and that this
was the result that for the 500 exposure uh which was only . 7 jewels disgrace this is the the place that the image is this ceramic cat holding a little glass B and this just shows the 2 different angles solvable emotion during the trying rainbow colors to change the direction of viewing so we're very happy with that showing that day it was possible to combining the what is 1 of the oldest imaging image recording techniques with 1 of the newest image recording techniques
we still need to use more work to find out whether building this thing is inside the sci-fi mention this conventional to
protect the surface of a line of electric chemically deposited layer of gold we didn't feel confident doing the image disappeared so the next 1 China
the optimum exposure still to be a determined and a refinement of the the sensitization development procedures but we show that the
daguerreotype does have the required resolution you can make holograms on characterize and this 1 dual square centimeter 458 meters and this is got possible applications in last could've craft silver sniffing injury but so what we thought was was pretty exciting just for the adventure of doing something new that had been and beef or and that's an element and
yet they are standing in front of the of the the the equipment that we use we thank you without the
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