Thank you Colin for this new section.
I need to purchase dye(s) for diffusion method.
Are Pinacyanol and Cyanine suitable to make Lippmann emulsion ?
I've read a paper about and seems that Lippmann used cyanine and chinoline red.
Valenta choice Erythrosine and Ives taked Isocol (??), Erythrosine and Pinacyanol.
So, I guess that Cyanine and Pinacyanol can be used.
Good news, in Bjelkhagen, in his paper, explains we don't need a mercury miror.
Since Hans use PFG-03 to make his Lippmann pictures and the Jeff's diffusion method gives grain size the same as PFG-03, we can make plate relatively cheap.
By the way, we can build a pinhole camera to make exposure.
Hmmm, a lot of works is waiting us. Damn, I like it !
Suitable dyes
-
Colin Kaminski
Suitable dyes
Here is an archive of the text:
1
Super-realistic-looking images based on colour holography and
Lippmann photography
Hans I. Bjelkhagen
De Montfort University, Centre for Modern Optics, The Gateway, Leicester LE1 9BH, UK
Abstract
Two imaging techniques will be presented which can create remarkable images. The first technique is colour holography,
which provides full parallax 3D colour images with a large field of view. The virtual colour image recorded in a holographic
plate represents the most realistic-looking image of an object that can be obtained today. The extensive field of view adds to
the illusion of beholding a real object rather than an image of it. In connection with the presentation, colour holograms will be
shown, including the artis t Anaït’s Flag colour hologram.
The other technique is interferential colour photography or Lippmann photography. This almost forgotten one-hundredyear-
old photographic technique is also remarkable. It is the only colour recording imaging technique which can record the
entire visible colour spectrum. It is not based on Maxwell’s tri-colour principle, the dominating principle behind most current
colour imaging techniques. The natural colour rendition makes this 2D photographic technique very interesting. For example,
the reproduction of human skin and metallic reflections are very natural looking, not possible to record in ordinary
photography. Examples of Lippmann photographs will be on display during the presentation.
2
Introduction
There is an interest in high-fidelity image recording techniques with perfect colour rendition, which can also accurately
capture the three-dimensional shape of an object. As regards colour rendition, Lippmann photography is the only imaging
technique that directly can record the entire colour spectrum of an object or a scene. Holography can record and store laser
light scattered off an object. The scattered light can be reconstructed by illuminating the holographic plate with the reference
light which creates a full parallax 3D image, visible behind the plate. The technique of recording holograms using three (red,
green, and blue) laser wavelengths provides extremely realistic-looking 3D images.
After the invention of black-and-white photography in the 19th century, there was a lot of interest in finding ways of
recording natural colour photographs. The somewhat difficult but very interesting interferential photographic technique
provided such images in 1891. Lippmann photography shows similarities to holography. In both cases an interference
structure is recorded in a fine-grain emulsion. The fundamental difference is that, in the Lippmann case, there is no phase
recording involved; the recorded interference structure is a result of phase-locking the light by the reflecting mirror. In
holography, the phase information is actually recorded, being encoded as an interference pattern created between the light
reflected from the object and a coherent reference beam. The recording of monochromatic light in a Lippmann photograph is
easy to understand, and it is very similar to recording a reflection volume hologram. A broadband polychromatic spectrum,
such as a landscape image, is very different. In this case, the recorded interference structure in the emulsion is located only
very close to the surface of the emulsion in contact with the reflecting mirror. A colour reflection hologram, on the other hand,
is a result of the three-colour RGB process involving three monochrome recordings superimposed in the same emulsion. In the
following both imaging techniques will be described and how to obtain the most realistic-looking 3D and 2D images.
Colour Holography
After 40 years since the appearance of the first laser-recorded monochromatic holograms the possibilities of recording fullcolour
high-quality holograms have now become a reality. What is referred to here, is the technique to obtain a colour 3D
image of an object where the colour rendition is as close as possible to the colour of the real object. In theory, the first
methods for recording colour holograms were established in the early 1960s. Already in 1964 Leith and Upatnieks proposed
multicolour wavefront reconstruction in one of their first papers on holography.1 The early methods concerned mainly
transmission holograms recorded with three different wavelengths from a laser or lasers, combined with different reference
directions to avoid cross-talk. The color hologram was then reconstructed by using the original laser wavelengths from the
corresponding reference directions. However, the complicated and expensive reconstruction setup prevented this technique
from becoming popular. More suitable for holographic colour recording is reflection holography. A reflection hologram can be
reconstructed and viewed in ordinary white light from a spotlight. Over the last few years many high-quality colour holograms
have been recorded mainly due to the introduction of new and improved panchromatic recording materials. On the market are
the Slavich2 ultrafine-grain silver halide emulsions as well as photopolymer materials, manufactured by E.I. du Pont de
Nemours & Co.3
Colour reflection holography presents no problems as regards the geometry of the recording setup, but the final result is
highly dependent on the recording material used and the processing techniques applied. Before panchromatic emulsions
existed the sandwich technique was used to make colour reflection holograms. Two plates were sandwiched together, in
which, e.g., two different types of recording materials were used. The most successful demonstration of the sandwich
recording technique was made by Kubota4 in Japan. He used a dichromated gelatin plate for the green (515 nm) and the blue
(488 nm) components, and an Agfa 8E75 silver halide plate for the red (633 nm) component of the image. Not until
panchromatic ultrafine-grain silver halide emulsions were introduced in Russia in the early nineties it was possible to record
high-quality colour holograms in a single emulsion layer as demonstrated by Bjelkhagen et al.5
3
Recording Materials
Silver halide materials
To be able to record high-quality colour reflection holograms it is necessary to use extremely low light-scattering recording
materials. This means, for example, the use of ultrafine-grain silver halide emulsions (grain size about 10 nm). Currently the
main commercial producer of such a material is the Slavich company. Some characteristics of the Slavich material are presented
in Table 1.
Table 1. Characteristics of the Slavich emulsion.
Silver halide material PFG-03c
Emulsion thickness 7 mm
Grain size 12 - 20 nm
Resolution ~10000 lp/mm1
Blue sensitivity ~1.0 - 1.5×10-3 J/cm2
Green sensitivity ~1.2 - 1.6×10-3 J/cm2
Red sensitivity ~0.8 - 1.2×10-3 J/cm2
Colour sensitivity peaked at: 633 nm, and 530 nm
In France, Gentet is manufacturing a new panchromatic silver halide emulsion with extremely fine grains. It is called the
Ultimate emulsion.6 Although impressive colour holograms have been recorded by Gentet, there is a question whether it is
possible to accurately record blue colour in the Ultimate plates. Gentet’s displayed holograms have, so far, shown red and
green objects with a hint of blue only. Blue is the most difficult colour to record in a silver halide emulsion. By avoiding blue it
is easy to record holograms with very low light scattering, which means that a very high signal-to-noise ratio can be obtained.
Nevertheless Gentet has shown that it is possible to improve silver halide emulsions for holographic recordings. Slavich plates
are by no means at the limit of silver halide emulsion technology. Unfortunately the highest-quality Ultimate colour emulsion
is not for sale, it is reserved for Gentet’s own holograms.
Photopolymer materials
The panchromatic photopolymer material from DuPont is an alternative recording material for colour holograms. Although,
being less sensitive than the ultrafine-grain silver halide emulsions, it has its special advantages of easy handling and dry
processing (only UV-curing and baking.) The colour photopolymer material needs an overall exposure of about 10 mJ/cm2.
After the exposure is finished, the film has to be exposed to strong white or UV light; about 100 mJ/cm2 exposure at 350-380
nm. After that, the hologram is put in an oven at a temperature of 120oC for two hours in order to increase the brightness of the
image. Recently DuPont announced that their materials will no longer be on the market. DuPont will be using the materials for
their own production of holograms and HOEs. Only special customers working in the field of optical security may still be able
to obtain DuPont photopolymer materials.
Laser Wavelengths for Colour Holograms
Choosing the correct recording wavelengths and the exact laser wavelengths is the key issue where accurate colour
reproduction is concerned. So far most colour holograms have been recorded using three primary laser wavelengths, resulting
in rather good colour rendition. However, some colours are not identical with the original colours and also colour
desaturation (colour shifting towards white) is a problem.
Hubel and Solymar7 provided a definition of colour recording in holography: “A holographic technique is said to reproduce
'true' colours if the average vector length of a standard set of coloured surfaces is less than 0.015 chromaticity coordinate
units, and the gamut area obtained by these surfaces is within 40% of the reference gamut. Average vector length and gamut
area should both be computed using a suitable white light standard reference illuminant.”
One important consideration is the question of whether three laser wavelengths are really sufficient for accurate colour
reproduction in holography. The wavelength selection problem has been discussed in several papers, for example, by Peercy
and Hesselink.8 They discussed the wavelength selection by investigating the sampling nature of the holographic process.
During the recording of a colour hologram, the chosen wavelengths point-sample the surface-reflectance functions of the
object. This sampling of colour perception can be investigated by the tristimulus value of points in the reconstructed
hologram, which is mathematically equivalent to the integral approximations for the tristimulus integrals. Peercy and Hesselink
used both Gaussian quadrature and Riemann summation for the approximation of the tristimulus integrals. In the first case
they found the wavelengths to be 437, 547, and 665 nm and in the second case the wavelengths were 475, 550, and 625 nm.
According to the above mentioned authors, the sampling approach indicates that three monochromatic sources will almost
4
always be insufficient for the accurate preservation of all of the object's spectral information. The authors claim that four or
even five laser wavelengths may be required. When using the relative weights from Gaussian quadrature, they obtained the
following four wavelengths:
ë1 = 424 nm, ë2 = 497 nm, ë3 = 598 nm, and ë4 = 678 nm.
When the relative weights from Riemann summation were used, they obtained the following four wavelengths:
ë1 = 460 nm, ë2 = 520 nm, ë3 = 580 nm, and ë4 = 640 nm.
Peercy and Hesselink found that for a particular test scene and with four sampling wavelengths, Riemann summation
performed significantly better than Gaussian quadrature.
Recently, Kubota et al.9 presented a theoretical analysis of colour holography based on four recording wavelengths. Using
the 1976 CIE chromaticity diagram, and by minimizing the distance between the selected object points in the diagram and the
corresponding reconstructed image points, they were able to obtain four optimal laser wavelengths. The calculation was
based on the nonlinear least square method. For the reproduction of nineteen selected colour patches of the Macbeth
ColorChecker the following four wavelengths were obtained:
ë1 = 459.1 nm, ë2 = 515.2 nm, ë3 = 585.0 nm, and ë4 = 663.2 nm.
Using these wavelengths, the average distance between the actual points and the recorded image points was 0.0087 CIE 1976
chromaticity units. If the same calculation was performed using only three recording wavelengths the following wavelengths
were obtained:
ë1 = 462.7 nm, ë2 = 528.0 nm, and ë3 = 599.6 nm.
In this case the average distance between the actual points and the recorded image points was 0.015 CIE 1976 chromaticity
units, which is twice larger than when four wavelengths are used. The four optimal wavelengths quoted in the paper by
Kubota et al.9 show good correlation with Peercy and Hesselink's wavelengths obtained when using Riemann summation.
Since it is difficult to find lasers which can provide the optimal four wavelengths in practice, Kubota et al.9 suggested the
following laser wavelengths to be employed:
ë1 = 457.9 nm (Ar-ion), ë2 = 514.5 nm (Ar-ion), ë3 = 580.0 nm (dye laser), and ë4 = 647.2 nm (Kr-ion).
It is obvious that by selecting the optimum four or even more laser recording wavelengths it is possible to record colour
holograms with extremely good colour rendition. Hopefully, tuneable lasers may provide the desired wavelengths in the future.
Only further experiments will show how accurately holographic colour reproduction can be performed in practice. Colour
rendition is the most important issue here and the question is, whether colour holography can really provide an absolutely
identical copy of the recorded object.
5
RGB laser wavelengths for colour holograms
Up until now most colour holograms have been recorded using only three laser wavelengths. Primary laser wavelengths are
found in the 1976 CIE chromaticity diagram in Fig. 1.
Figure 1. The 1976 CIE uniform scales chromaticity diagram shows the gamut of surface colours and positions of common
laser wavelengths. Optimal colour-recording laser wavelengths are also indicated
6
Figure 2. Setup for recording colour holograms
Recording Colour Holograms
Denisyuk setup for recording colour holograms
A typical reflection hologram recording setup is illustrated in Fig. 2. For most display purposes, the very large field of view
obtainable in a single-beam Denisyuk hologram is very attractive. Therefore such a recording scheme is selected. The different
laser beams necessary for the exposure of the object pass through the same beam expander and spatial filter. The light
reflected from the object constitutes the object beam of the hologram. The reference beam is formed by the three expanded
laser beams. This "white" laser beam illuminates both the holographic plate and the object itself through the plate. Each of the
three primary laser wavelengths forms its individual interference pattern in the emulsion, all the patterns being recorded
simultaneously during the exposure. In this way, three holographic images (a red, a green, and a blue image) are superimposed
on one another in the emulsion. The three laser wavelengths used by the author are: 476 nm, provided by an argon ion laser,
532 nm, provided by a cw frequency-doubled Nd:YAG laser, and 647 nm, provided by a krypton ion laser. Two dichroic filters
are used for combining the three laser beams. By using the dichroic filter beam combination technique it is possible to perform
simultaneous exposure recording, which makes it possible to control independently the RGB ratio and the overall exposure
energy in the emulsion. The RGB ratio can be varied by individually changing the output power of the lasers, while the overall
exposure energy is controlled solely by the exposure time. The overall energy density for exposure is about 3 mJ/cm2 for
Slavich material.
7
Processing of colour holograms
The processing of holograms recorded in silver halide emulsions is of critical importance. The Slavich emulsion is rather soft,
and it is important to harden the emulsion before development and bleaching take place. Emulsion shrinkage and other
emulsion distortions caused by active solutions used for the processing of holograms must be avoided. The processing steps
are summarized in Table 2. It is very important to employ a suitable bleach bath to convert the developed amplitude hologram
into a phase hologram. The bleach must create an almost stain-free clear emulsion so as not to affect the colour image. In
addition, no emulsion shrinkage can be permitted, as it would change the colours of the image. Washing and drying must also
be done so that no shrinkage occurs. Finally, to prevent any potential emulsion thickness changes caused by variations in
humidity, the emulsion needs to be protected by a glass plate being sealed onto the holographic plate.
Table 2: Colour holography processing steps.
1. Tanning in a Formaldehyde solution 6 min
2. Short rinse 5 sec
3. Development in the CWC2 developer 3 min
4. Wash 5 min
5. Bleaching in the PBU-amidol bleach ~5 min
6. Wash 10 min
7. Soaking in acetic acid bath (printout prevention) 1 min
8. Short rinse 1 min
9. Washing in distilled water with wetting agent added 1 min
10. Air drying
Recorded Colour Holograms
A specially designed test object consisting of the 1931 CIE chromaticity diagram is used for the colour balance adjustments
and exposure tests. The Macbeth ColorChecker chart is also often used for colour rendering tests. A recorded colour
hologram of the CIE targets is presented in following. The spotlight used to reconstruct that hologram as well as all the other
recorded holographic images was a 12-V 50-W halogen lamp. The colour balance for the recording of a colour hologram must
be adjusted with what type of spotlight that is going to be used for the display of the finished hologram in mind. Figure 3
shows a typical normalized spectrum obtained from a white area of the colour test target hologram. One should note the high
diffraction efficiency in blue, needed to compensate for the rather low blue light emission of the halogen spotlight. The noise
level, mainly in the blue part of the spectrum, is visible and low. The three peaks are exactly at the recording wavelengths; i.e.,
647, 532, and 476 nm. A reproduction of the CIE hologram is presented in Fig. 4.
A few examples of colour display holograms are shown in Figs. 5 – 7. In Fig. 5 a large Chinese Vase was recorded in a 30 cm
x 40 cm glass plate. Figure 6 depicts a hologram of a little French house in a 4” x 5” plate and in Fig. 7, six Peking masks were
recorded in another 4”x 5” Slavich plate.
In 1995 Anaït produced two interesting 8” by 10” colour holograms at Lake Forest College with assistance of the author.
Two pseudoscopic objects were made by Anaït with the intention to have the reconstructed holographic images of the
recorded objects to appear in front of the plate. One of her holograms is illustrated here: the Flag hologram, in Fig. 8. The
other hologram recorded at Lake Forest College was the Cave hologram.
8
Figure 3. Normalized spectrum from a white area of a colour test target hologram
Figure 4. Hologram of the CIE test object recorded
with 476, 532, and 647 nm laser wavelengths
9
Figure 6 . French House, 4” x 5” plate
Figure 5. Chinese Vase, 30 cm x 40 cm plate
Figure 7. Peking Masks, 4” x 5” plate
10
Figure 8. The Flag colour hologram by Anaït, an 8”x 10” plate
Lippmann Photography
History and principle of interferential photography
Gabriel Lippmann (1845 - 1921) was able to record the first colour photographs for more than one hundred years ago. His
technique has become known as interferential photography or interference colour photography. In 1891 Lippmann
announced that he had succeeded in recording a true-colour spectrum.10 A little more than one year later Lippmann displayed
four colour photographs of different objects.11 Although the new photographic colour recording technique, also known as
Lippmann photography, was extremely interesting from a scientific point of view, it was not very effective for colour
photography since the technique was complicated and the exposure times were too long for practical use. The difficulty in
viewing the photographs was another contributing factor, in addition to the copying problem, which prevented Lippmann
photography from becoming a practical photographic colour-recording method. However, one-hundred-year-old Lippmann
photographs are very beautiful and the fact that the colours are so well preserved indicates something about their archival
properties. Lippmann was awarded the Nobel Prize in physics for his invention in 1908.
The principle of Lippmann photography is shown in Fig. 9. Because of the demand for high resolving power in making
Lippmann photographs, the material had to be a very fine-grain emulsion and thus of very low sensitivity. The coating of
emulsion on Lippmann plates was brought in contact with a highly reflective surface, mercury, reflecting the light into the
emulsion and then interfering with the light coming from the other side of the emulsion. The standing waves of the interfering
light produced a very fine fringe pattern throughout the emulsion with a periodic spacing of ë/(2n) that had to be recorded (ë
is the wavelength of light in air and n is the refractive index of the emulsion). The colour information was stored locally in this
way.
11
Red
Green
Figure 9. The principle of Lippmann photography
The larger the separation between the fringes, the longer was the wavelength of the recorded part of image information. This is
only correct when rather monochromatic colours are recorded. A polychrome recording is more complex, and was first
mathematically treated by Lippmann.12
When the developed photograph was viewed in white light, different parts of the recorded image produced different colours.
This was due to the separation of the recorded fringes in the emulsion. The light was reflected from the fringes, creating
different colours corresponding to the original ones that had produced them during the recording. In order to observe the
correct colours, the illumination and observation have to be at normal incidence. If the angle changes, the colours of the image
will change. This change of colour with angle, known as iridescence, is of the same type as found in peacock feathers and
mother of pearl. The image is recorded as a Bragg structure.
There was very little interest in making silver-halide plates of the Lippmann type after this type of photography disappeared.
However, the need for such plates came back when holography started to become popular in the early 1960s. Recent progress
in development of colour holography has opened up new possibilities to investigate Lippmann photography again. Using new
and improved panchromatic recording materials (silver-halide and photopolymer) combined with special processing
techniques for colour holograms have made it possible to record interference colour photographs.
Modern Lippmann photography
Lippmann photography shows similarities to holography. In both cases an interference structure is recorded in a fine-grain
emulsion as a b/w pattern. To some extent, a Lippmann photograph can be regarded as a reflection image-plane hologram
recorded with light of very short temporal coherence. The reference wave is a diffuse complex wavefront (the mirror image of
the exit pupil of the recording lens.)
The recording of monochromatic light in a Lippmann emulsion is easy to understand, and it is very similar to recording a
reflection volume hologram. A broadband polychromatic spectrum, such as a landscape image, is very different. In this case,
the recorded interference structure in the emulsion is located only very close to the surface of the emulsion in contact with the
reflecting mirror. Bjelkhagen et al.13 and Bjelkhagen14-16 demonstrated the possibility to record Lippmann photographs in
Slavich PFG-03c panchromatic holographic emulsion. To record Lippmann photographs, it is not necessary to use mercury as
the light reflector. The gelatin-air interface can act as a reflector of light. The plate is inserted in a conventional dark slide with
the emulsion side facing away from camera lens. Inside the adapter, black velvet is attached in order to reduce scattered light.
When the plate is exposed without mercury, the exposure time is slightly increased compared to a recording with a mercury
reflector.
12
Figure 10. Light reflected at an optically thicker medium (mercury, R 1) and at an optically thinner medium (air, R 2).
S is the gelatin emulsion.
The reason why it is possible to obtain a Lippmann photograph without mercury can be explained in the following way. One
must study the difference between a reflection at the mercury surface or obtained at the gelatin-air interface, illustrated in Fig.
10. A node is located at the mercury reflector (an optically thicker medium than gelatin), which means at the gelatin surface.
The phase shift there is . On the contrary, a crest is located at the surface when the reflection is obtained from the gelatinair
interface (an optically thinner medium than gelatin), which means, since no phase shift occurs in this case, a silver layer will
be created at the emulsion surface after development. In the mercury case the first silver layer is located at a distance of ë/4
inside the gelatin emulsion. When using air reflection, the exposure must be slightly increased to bring the recording up on the
linear part of the Hurter-Driffield curve. The weaker fringe modulation caused by the Fresnel reflection at the air-gelatin
interface is amplified in the developing process. The problem, pointed out by Wiener, about the surface reflection being out of
phase with the image when viewing a Lippmann photograph only exists in the mercury case. When using the air reflector, the
surface reflection is in phase with the image.
The processing of the Lippmann photographs is critical. The interference pattern is recorded only in a very thin volume at
the top of the emuls ion. This area has to be maintained intact after processing. Emulsion shrinkage and other emulsion
distortions caused by the developer must be avoided. Among the old Lippmann developers, the Lumière pyrogallol-ammonia
developer give good results. To avoid shrinkage the plates are not fixed, only washed after development.
A recorded Lippmann photograph is a portrait of the author reproduced in Fig.11. The exposure time was two minutes at
aperture F:4 using an Auto Graflex 4" by 5" camera equipped with a Kodak Aero Ektar F:2.5, 178 mm lens. After being
processed, the back of the plate was painted black. For better viewing of the image, a wedged glass plate (Wiener prism) was
cemented to the emulsion side, as for old Lippmann photographs. The reproduction of human skin is remarkable realistic in a
Lippmann photograph. Also metallic reflections are accurately recorded.
Conclusions
Large-format colour reflection holograms can be recorded with rather good colour rendition. However, further improvements
are needed, e.g., as regards colour saturation, image resolution, signal-to-noise ratio, dynamic range. Employing emulsions
with a grain size less than 10 nm and four recording laser wavelengths will soon make it possible to make a holographic image
that would not be possible to distinguish from the object itself. The virtual colour image behind a holographic plate represents
the most realistic-looking image of an object that can be recorded today. This perfect 3D imaging technique has many obvious
applications, e.g., for displaying unique and expensive artefacts as well as in advertising.
Modern Lippmann photography may have limited applications in photography and colour imaging, but may very well appeal
to artists and art photographers. The Lippmann photograph is virtually impossible to copy, which makes it a unique, one of its
kind, photographic recording combined with extremely high archival stability. Since the quality of a Lippmann photograph
mainly depends on the recording material, special isochromatic ultrafine-grain emulsions are absolutely necessary in order to
record absolute correct colour photographs. The holographic plates used here are not really designed for Lippmann
photography and thus it is not possible to demonstrate the perfect quality that theoretically can be obtained with interferential
colour imaging.
13
Figure 11. Lippmann portrait of the author
References
1. E. N. Leith and J. Upatnieks, “Wavefront reconstruction with diffused illumination and three-dimensional objects,” J. Opt.
Soc. Am. 54, pp. 1295-1301, 1964.
2. S. J. Zacharovas, D. B. Ratcliffe, G. R. Skokov, S. P. Vorobiov, P. I. Kumonko, and Yu. A. Sazonov, “Recent advances in
holographic materials from Slavich,” in HOLOGRAPHY 2000, T. H. Jeong, and W. K. Sobotka, eds., Proc. SPIE 4149, pp. 73-
80, 2000.
3. M. Watanabe, T. Matsuyama, D. Kodama, and T. Hotta, “Mass-produced color graphic arts holograms,” in Practical
Holography XII, S. A. Benton, ed. Proc. SPIE 3637, pp. 204-212, 1999.
4. T. Kubota, “Recording of high quality color holograms,” Appl. Opt. 25, pp. 4141-4145, 1986.
5. H. I. Bjelkhagen, T. H. Jeong, and D. Vukièeviæ, “Color reflection holograms recorded in a ultrahigh-resolution single-layer
silver halide emulsion,” J. Imaging Sci. Technol. 40, pp. 134-146, 1996.
6. Y. Gentet and P. Gentet,“"Ultimate" emulsion and its applications: a laboratory-made silver halide emulsion of optimized
quality for monochromatic pulsed and full color holography,” in HOLOGRAPHY 2000, T. H. Jeong and W. K. Sobotka, eds.,
Proc. SPIE 4149, pp. 56-62, 2000.
7. P. M. Hubel and L. Solymar, “Color reflection holography: Theory and experiment,” Appl. Opt. 30, pp. 4190-4203, 1991.
8. M. S. Peercy and L. Hesselink, “Wavelength selection for true-color holography,” Appl. Opt. 33, pp. 6811-6817, 1994.
9. T. Kubota, E. Takabayashi, T. Kashiwagi, M. Watanabe, and K. Ueda, “Color reflection holography using four recording
wavelengths,” in Practical Holography XV and Holographic Materials VII, S. A. Benton, S. H. Stevenson, and T. J. Trout,
eds., Proc. SPIE 4296, pp. 126-133, 2001.
10. G. Lippmann, “La photographie des couleurs,” C. R. Hebd. Séances Acad. Sci. 112, pp. 274-275, 1891.
11. G. Lippmann, “La photographie des couleurs [deuxième note],” C. R. Hebd. Séances Acad. Sci. 114, pp. 961-962, 1892.
12. G. Lippmann, “Sur la théorie de la photographie des couleurs simples et composées par la méthode interférentielle,” J.
Physique 3 (3), pp. 97-107, 1894.
13. H. I. Bjelkhagen, T. H. Jeong, and R. J. Ro, “Old and modern Lippmann photography,” in Sixth Int'l Symposium on Display
Holography, T. H. Jeong, ed., Proc. SPIE 3358, pp. 72-83, 1998.
14. H. I. Bjelkhagen, “Lippmann photographs recorded in DuPont color photopolymer material,” in Practical Holography XI
and Holographic Materials III, S. A. Benton and T. J. Trout, eds., Proc. SPIE 3011, pp. 358-366, 1997.
15. H. I. Bjelkhagen, “New optical security device based on one-hundred-year-old photographic technique,” Opt. Eng. 38, pp.
55-61, 1999.
16. H. I. Bjelkhagen, “Lippmann photography: reviving an early colour process,” History of Photography 23, pp. 274-280,
1999.
1
Super-realistic-looking images based on colour holography and
Lippmann photography
Hans I. Bjelkhagen
De Montfort University, Centre for Modern Optics, The Gateway, Leicester LE1 9BH, UK
Abstract
Two imaging techniques will be presented which can create remarkable images. The first technique is colour holography,
which provides full parallax 3D colour images with a large field of view. The virtual colour image recorded in a holographic
plate represents the most realistic-looking image of an object that can be obtained today. The extensive field of view adds to
the illusion of beholding a real object rather than an image of it. In connection with the presentation, colour holograms will be
shown, including the artis t Anaït’s Flag colour hologram.
The other technique is interferential colour photography or Lippmann photography. This almost forgotten one-hundredyear-
old photographic technique is also remarkable. It is the only colour recording imaging technique which can record the
entire visible colour spectrum. It is not based on Maxwell’s tri-colour principle, the dominating principle behind most current
colour imaging techniques. The natural colour rendition makes this 2D photographic technique very interesting. For example,
the reproduction of human skin and metallic reflections are very natural looking, not possible to record in ordinary
photography. Examples of Lippmann photographs will be on display during the presentation.
2
Introduction
There is an interest in high-fidelity image recording techniques with perfect colour rendition, which can also accurately
capture the three-dimensional shape of an object. As regards colour rendition, Lippmann photography is the only imaging
technique that directly can record the entire colour spectrum of an object or a scene. Holography can record and store laser
light scattered off an object. The scattered light can be reconstructed by illuminating the holographic plate with the reference
light which creates a full parallax 3D image, visible behind the plate. The technique of recording holograms using three (red,
green, and blue) laser wavelengths provides extremely realistic-looking 3D images.
After the invention of black-and-white photography in the 19th century, there was a lot of interest in finding ways of
recording natural colour photographs. The somewhat difficult but very interesting interferential photographic technique
provided such images in 1891. Lippmann photography shows similarities to holography. In both cases an interference
structure is recorded in a fine-grain emulsion. The fundamental difference is that, in the Lippmann case, there is no phase
recording involved; the recorded interference structure is a result of phase-locking the light by the reflecting mirror. In
holography, the phase information is actually recorded, being encoded as an interference pattern created between the light
reflected from the object and a coherent reference beam. The recording of monochromatic light in a Lippmann photograph is
easy to understand, and it is very similar to recording a reflection volume hologram. A broadband polychromatic spectrum,
such as a landscape image, is very different. In this case, the recorded interference structure in the emulsion is located only
very close to the surface of the emulsion in contact with the reflecting mirror. A colour reflection hologram, on the other hand,
is a result of the three-colour RGB process involving three monochrome recordings superimposed in the same emulsion. In the
following both imaging techniques will be described and how to obtain the most realistic-looking 3D and 2D images.
Colour Holography
After 40 years since the appearance of the first laser-recorded monochromatic holograms the possibilities of recording fullcolour
high-quality holograms have now become a reality. What is referred to here, is the technique to obtain a colour 3D
image of an object where the colour rendition is as close as possible to the colour of the real object. In theory, the first
methods for recording colour holograms were established in the early 1960s. Already in 1964 Leith and Upatnieks proposed
multicolour wavefront reconstruction in one of their first papers on holography.1 The early methods concerned mainly
transmission holograms recorded with three different wavelengths from a laser or lasers, combined with different reference
directions to avoid cross-talk. The color hologram was then reconstructed by using the original laser wavelengths from the
corresponding reference directions. However, the complicated and expensive reconstruction setup prevented this technique
from becoming popular. More suitable for holographic colour recording is reflection holography. A reflection hologram can be
reconstructed and viewed in ordinary white light from a spotlight. Over the last few years many high-quality colour holograms
have been recorded mainly due to the introduction of new and improved panchromatic recording materials. On the market are
the Slavich2 ultrafine-grain silver halide emulsions as well as photopolymer materials, manufactured by E.I. du Pont de
Nemours & Co.3
Colour reflection holography presents no problems as regards the geometry of the recording setup, but the final result is
highly dependent on the recording material used and the processing techniques applied. Before panchromatic emulsions
existed the sandwich technique was used to make colour reflection holograms. Two plates were sandwiched together, in
which, e.g., two different types of recording materials were used. The most successful demonstration of the sandwich
recording technique was made by Kubota4 in Japan. He used a dichromated gelatin plate for the green (515 nm) and the blue
(488 nm) components, and an Agfa 8E75 silver halide plate for the red (633 nm) component of the image. Not until
panchromatic ultrafine-grain silver halide emulsions were introduced in Russia in the early nineties it was possible to record
high-quality colour holograms in a single emulsion layer as demonstrated by Bjelkhagen et al.5
3
Recording Materials
Silver halide materials
To be able to record high-quality colour reflection holograms it is necessary to use extremely low light-scattering recording
materials. This means, for example, the use of ultrafine-grain silver halide emulsions (grain size about 10 nm). Currently the
main commercial producer of such a material is the Slavich company. Some characteristics of the Slavich material are presented
in Table 1.
Table 1. Characteristics of the Slavich emulsion.
Silver halide material PFG-03c
Emulsion thickness 7 mm
Grain size 12 - 20 nm
Resolution ~10000 lp/mm1
Blue sensitivity ~1.0 - 1.5×10-3 J/cm2
Green sensitivity ~1.2 - 1.6×10-3 J/cm2
Red sensitivity ~0.8 - 1.2×10-3 J/cm2
Colour sensitivity peaked at: 633 nm, and 530 nm
In France, Gentet is manufacturing a new panchromatic silver halide emulsion with extremely fine grains. It is called the
Ultimate emulsion.6 Although impressive colour holograms have been recorded by Gentet, there is a question whether it is
possible to accurately record blue colour in the Ultimate plates. Gentet’s displayed holograms have, so far, shown red and
green objects with a hint of blue only. Blue is the most difficult colour to record in a silver halide emulsion. By avoiding blue it
is easy to record holograms with very low light scattering, which means that a very high signal-to-noise ratio can be obtained.
Nevertheless Gentet has shown that it is possible to improve silver halide emulsions for holographic recordings. Slavich plates
are by no means at the limit of silver halide emulsion technology. Unfortunately the highest-quality Ultimate colour emulsion
is not for sale, it is reserved for Gentet’s own holograms.
Photopolymer materials
The panchromatic photopolymer material from DuPont is an alternative recording material for colour holograms. Although,
being less sensitive than the ultrafine-grain silver halide emulsions, it has its special advantages of easy handling and dry
processing (only UV-curing and baking.) The colour photopolymer material needs an overall exposure of about 10 mJ/cm2.
After the exposure is finished, the film has to be exposed to strong white or UV light; about 100 mJ/cm2 exposure at 350-380
nm. After that, the hologram is put in an oven at a temperature of 120oC for two hours in order to increase the brightness of the
image. Recently DuPont announced that their materials will no longer be on the market. DuPont will be using the materials for
their own production of holograms and HOEs. Only special customers working in the field of optical security may still be able
to obtain DuPont photopolymer materials.
Laser Wavelengths for Colour Holograms
Choosing the correct recording wavelengths and the exact laser wavelengths is the key issue where accurate colour
reproduction is concerned. So far most colour holograms have been recorded using three primary laser wavelengths, resulting
in rather good colour rendition. However, some colours are not identical with the original colours and also colour
desaturation (colour shifting towards white) is a problem.
Hubel and Solymar7 provided a definition of colour recording in holography: “A holographic technique is said to reproduce
'true' colours if the average vector length of a standard set of coloured surfaces is less than 0.015 chromaticity coordinate
units, and the gamut area obtained by these surfaces is within 40% of the reference gamut. Average vector length and gamut
area should both be computed using a suitable white light standard reference illuminant.”
One important consideration is the question of whether three laser wavelengths are really sufficient for accurate colour
reproduction in holography. The wavelength selection problem has been discussed in several papers, for example, by Peercy
and Hesselink.8 They discussed the wavelength selection by investigating the sampling nature of the holographic process.
During the recording of a colour hologram, the chosen wavelengths point-sample the surface-reflectance functions of the
object. This sampling of colour perception can be investigated by the tristimulus value of points in the reconstructed
hologram, which is mathematically equivalent to the integral approximations for the tristimulus integrals. Peercy and Hesselink
used both Gaussian quadrature and Riemann summation for the approximation of the tristimulus integrals. In the first case
they found the wavelengths to be 437, 547, and 665 nm and in the second case the wavelengths were 475, 550, and 625 nm.
According to the above mentioned authors, the sampling approach indicates that three monochromatic sources will almost
4
always be insufficient for the accurate preservation of all of the object's spectral information. The authors claim that four or
even five laser wavelengths may be required. When using the relative weights from Gaussian quadrature, they obtained the
following four wavelengths:
ë1 = 424 nm, ë2 = 497 nm, ë3 = 598 nm, and ë4 = 678 nm.
When the relative weights from Riemann summation were used, they obtained the following four wavelengths:
ë1 = 460 nm, ë2 = 520 nm, ë3 = 580 nm, and ë4 = 640 nm.
Peercy and Hesselink found that for a particular test scene and with four sampling wavelengths, Riemann summation
performed significantly better than Gaussian quadrature.
Recently, Kubota et al.9 presented a theoretical analysis of colour holography based on four recording wavelengths. Using
the 1976 CIE chromaticity diagram, and by minimizing the distance between the selected object points in the diagram and the
corresponding reconstructed image points, they were able to obtain four optimal laser wavelengths. The calculation was
based on the nonlinear least square method. For the reproduction of nineteen selected colour patches of the Macbeth
ColorChecker the following four wavelengths were obtained:
ë1 = 459.1 nm, ë2 = 515.2 nm, ë3 = 585.0 nm, and ë4 = 663.2 nm.
Using these wavelengths, the average distance between the actual points and the recorded image points was 0.0087 CIE 1976
chromaticity units. If the same calculation was performed using only three recording wavelengths the following wavelengths
were obtained:
ë1 = 462.7 nm, ë2 = 528.0 nm, and ë3 = 599.6 nm.
In this case the average distance between the actual points and the recorded image points was 0.015 CIE 1976 chromaticity
units, which is twice larger than when four wavelengths are used. The four optimal wavelengths quoted in the paper by
Kubota et al.9 show good correlation with Peercy and Hesselink's wavelengths obtained when using Riemann summation.
Since it is difficult to find lasers which can provide the optimal four wavelengths in practice, Kubota et al.9 suggested the
following laser wavelengths to be employed:
ë1 = 457.9 nm (Ar-ion), ë2 = 514.5 nm (Ar-ion), ë3 = 580.0 nm (dye laser), and ë4 = 647.2 nm (Kr-ion).
It is obvious that by selecting the optimum four or even more laser recording wavelengths it is possible to record colour
holograms with extremely good colour rendition. Hopefully, tuneable lasers may provide the desired wavelengths in the future.
Only further experiments will show how accurately holographic colour reproduction can be performed in practice. Colour
rendition is the most important issue here and the question is, whether colour holography can really provide an absolutely
identical copy of the recorded object.
5
RGB laser wavelengths for colour holograms
Up until now most colour holograms have been recorded using only three laser wavelengths. Primary laser wavelengths are
found in the 1976 CIE chromaticity diagram in Fig. 1.
Figure 1. The 1976 CIE uniform scales chromaticity diagram shows the gamut of surface colours and positions of common
laser wavelengths. Optimal colour-recording laser wavelengths are also indicated
6
Figure 2. Setup for recording colour holograms
Recording Colour Holograms
Denisyuk setup for recording colour holograms
A typical reflection hologram recording setup is illustrated in Fig. 2. For most display purposes, the very large field of view
obtainable in a single-beam Denisyuk hologram is very attractive. Therefore such a recording scheme is selected. The different
laser beams necessary for the exposure of the object pass through the same beam expander and spatial filter. The light
reflected from the object constitutes the object beam of the hologram. The reference beam is formed by the three expanded
laser beams. This "white" laser beam illuminates both the holographic plate and the object itself through the plate. Each of the
three primary laser wavelengths forms its individual interference pattern in the emulsion, all the patterns being recorded
simultaneously during the exposure. In this way, three holographic images (a red, a green, and a blue image) are superimposed
on one another in the emulsion. The three laser wavelengths used by the author are: 476 nm, provided by an argon ion laser,
532 nm, provided by a cw frequency-doubled Nd:YAG laser, and 647 nm, provided by a krypton ion laser. Two dichroic filters
are used for combining the three laser beams. By using the dichroic filter beam combination technique it is possible to perform
simultaneous exposure recording, which makes it possible to control independently the RGB ratio and the overall exposure
energy in the emulsion. The RGB ratio can be varied by individually changing the output power of the lasers, while the overall
exposure energy is controlled solely by the exposure time. The overall energy density for exposure is about 3 mJ/cm2 for
Slavich material.
7
Processing of colour holograms
The processing of holograms recorded in silver halide emulsions is of critical importance. The Slavich emulsion is rather soft,
and it is important to harden the emulsion before development and bleaching take place. Emulsion shrinkage and other
emulsion distortions caused by active solutions used for the processing of holograms must be avoided. The processing steps
are summarized in Table 2. It is very important to employ a suitable bleach bath to convert the developed amplitude hologram
into a phase hologram. The bleach must create an almost stain-free clear emulsion so as not to affect the colour image. In
addition, no emulsion shrinkage can be permitted, as it would change the colours of the image. Washing and drying must also
be done so that no shrinkage occurs. Finally, to prevent any potential emulsion thickness changes caused by variations in
humidity, the emulsion needs to be protected by a glass plate being sealed onto the holographic plate.
Table 2: Colour holography processing steps.
1. Tanning in a Formaldehyde solution 6 min
2. Short rinse 5 sec
3. Development in the CWC2 developer 3 min
4. Wash 5 min
5. Bleaching in the PBU-amidol bleach ~5 min
6. Wash 10 min
7. Soaking in acetic acid bath (printout prevention) 1 min
8. Short rinse 1 min
9. Washing in distilled water with wetting agent added 1 min
10. Air drying
Recorded Colour Holograms
A specially designed test object consisting of the 1931 CIE chromaticity diagram is used for the colour balance adjustments
and exposure tests. The Macbeth ColorChecker chart is also often used for colour rendering tests. A recorded colour
hologram of the CIE targets is presented in following. The spotlight used to reconstruct that hologram as well as all the other
recorded holographic images was a 12-V 50-W halogen lamp. The colour balance for the recording of a colour hologram must
be adjusted with what type of spotlight that is going to be used for the display of the finished hologram in mind. Figure 3
shows a typical normalized spectrum obtained from a white area of the colour test target hologram. One should note the high
diffraction efficiency in blue, needed to compensate for the rather low blue light emission of the halogen spotlight. The noise
level, mainly in the blue part of the spectrum, is visible and low. The three peaks are exactly at the recording wavelengths; i.e.,
647, 532, and 476 nm. A reproduction of the CIE hologram is presented in Fig. 4.
A few examples of colour display holograms are shown in Figs. 5 – 7. In Fig. 5 a large Chinese Vase was recorded in a 30 cm
x 40 cm glass plate. Figure 6 depicts a hologram of a little French house in a 4” x 5” plate and in Fig. 7, six Peking masks were
recorded in another 4”x 5” Slavich plate.
In 1995 Anaït produced two interesting 8” by 10” colour holograms at Lake Forest College with assistance of the author.
Two pseudoscopic objects were made by Anaït with the intention to have the reconstructed holographic images of the
recorded objects to appear in front of the plate. One of her holograms is illustrated here: the Flag hologram, in Fig. 8. The
other hologram recorded at Lake Forest College was the Cave hologram.
8
Figure 3. Normalized spectrum from a white area of a colour test target hologram
Figure 4. Hologram of the CIE test object recorded
with 476, 532, and 647 nm laser wavelengths
9
Figure 6 . French House, 4” x 5” plate
Figure 5. Chinese Vase, 30 cm x 40 cm plate
Figure 7. Peking Masks, 4” x 5” plate
10
Figure 8. The Flag colour hologram by Anaït, an 8”x 10” plate
Lippmann Photography
History and principle of interferential photography
Gabriel Lippmann (1845 - 1921) was able to record the first colour photographs for more than one hundred years ago. His
technique has become known as interferential photography or interference colour photography. In 1891 Lippmann
announced that he had succeeded in recording a true-colour spectrum.10 A little more than one year later Lippmann displayed
four colour photographs of different objects.11 Although the new photographic colour recording technique, also known as
Lippmann photography, was extremely interesting from a scientific point of view, it was not very effective for colour
photography since the technique was complicated and the exposure times were too long for practical use. The difficulty in
viewing the photographs was another contributing factor, in addition to the copying problem, which prevented Lippmann
photography from becoming a practical photographic colour-recording method. However, one-hundred-year-old Lippmann
photographs are very beautiful and the fact that the colours are so well preserved indicates something about their archival
properties. Lippmann was awarded the Nobel Prize in physics for his invention in 1908.
The principle of Lippmann photography is shown in Fig. 9. Because of the demand for high resolving power in making
Lippmann photographs, the material had to be a very fine-grain emulsion and thus of very low sensitivity. The coating of
emulsion on Lippmann plates was brought in contact with a highly reflective surface, mercury, reflecting the light into the
emulsion and then interfering with the light coming from the other side of the emulsion. The standing waves of the interfering
light produced a very fine fringe pattern throughout the emulsion with a periodic spacing of ë/(2n) that had to be recorded (ë
is the wavelength of light in air and n is the refractive index of the emulsion). The colour information was stored locally in this
way.
11
Red
Green
Figure 9. The principle of Lippmann photography
The larger the separation between the fringes, the longer was the wavelength of the recorded part of image information. This is
only correct when rather monochromatic colours are recorded. A polychrome recording is more complex, and was first
mathematically treated by Lippmann.12
When the developed photograph was viewed in white light, different parts of the recorded image produced different colours.
This was due to the separation of the recorded fringes in the emulsion. The light was reflected from the fringes, creating
different colours corresponding to the original ones that had produced them during the recording. In order to observe the
correct colours, the illumination and observation have to be at normal incidence. If the angle changes, the colours of the image
will change. This change of colour with angle, known as iridescence, is of the same type as found in peacock feathers and
mother of pearl. The image is recorded as a Bragg structure.
There was very little interest in making silver-halide plates of the Lippmann type after this type of photography disappeared.
However, the need for such plates came back when holography started to become popular in the early 1960s. Recent progress
in development of colour holography has opened up new possibilities to investigate Lippmann photography again. Using new
and improved panchromatic recording materials (silver-halide and photopolymer) combined with special processing
techniques for colour holograms have made it possible to record interference colour photographs.
Modern Lippmann photography
Lippmann photography shows similarities to holography. In both cases an interference structure is recorded in a fine-grain
emulsion as a b/w pattern. To some extent, a Lippmann photograph can be regarded as a reflection image-plane hologram
recorded with light of very short temporal coherence. The reference wave is a diffuse complex wavefront (the mirror image of
the exit pupil of the recording lens.)
The recording of monochromatic light in a Lippmann emulsion is easy to understand, and it is very similar to recording a
reflection volume hologram. A broadband polychromatic spectrum, such as a landscape image, is very different. In this case,
the recorded interference structure in the emulsion is located only very close to the surface of the emulsion in contact with the
reflecting mirror. Bjelkhagen et al.13 and Bjelkhagen14-16 demonstrated the possibility to record Lippmann photographs in
Slavich PFG-03c panchromatic holographic emulsion. To record Lippmann photographs, it is not necessary to use mercury as
the light reflector. The gelatin-air interface can act as a reflector of light. The plate is inserted in a conventional dark slide with
the emulsion side facing away from camera lens. Inside the adapter, black velvet is attached in order to reduce scattered light.
When the plate is exposed without mercury, the exposure time is slightly increased compared to a recording with a mercury
reflector.
12
Figure 10. Light reflected at an optically thicker medium (mercury, R 1) and at an optically thinner medium (air, R 2).
S is the gelatin emulsion.
The reason why it is possible to obtain a Lippmann photograph without mercury can be explained in the following way. One
must study the difference between a reflection at the mercury surface or obtained at the gelatin-air interface, illustrated in Fig.
10. A node is located at the mercury reflector (an optically thicker medium than gelatin), which means at the gelatin surface.
The phase shift there is . On the contrary, a crest is located at the surface when the reflection is obtained from the gelatinair
interface (an optically thinner medium than gelatin), which means, since no phase shift occurs in this case, a silver layer will
be created at the emulsion surface after development. In the mercury case the first silver layer is located at a distance of ë/4
inside the gelatin emulsion. When using air reflection, the exposure must be slightly increased to bring the recording up on the
linear part of the Hurter-Driffield curve. The weaker fringe modulation caused by the Fresnel reflection at the air-gelatin
interface is amplified in the developing process. The problem, pointed out by Wiener, about the surface reflection being out of
phase with the image when viewing a Lippmann photograph only exists in the mercury case. When using the air reflector, the
surface reflection is in phase with the image.
The processing of the Lippmann photographs is critical. The interference pattern is recorded only in a very thin volume at
the top of the emuls ion. This area has to be maintained intact after processing. Emulsion shrinkage and other emulsion
distortions caused by the developer must be avoided. Among the old Lippmann developers, the Lumière pyrogallol-ammonia
developer give good results. To avoid shrinkage the plates are not fixed, only washed after development.
A recorded Lippmann photograph is a portrait of the author reproduced in Fig.11. The exposure time was two minutes at
aperture F:4 using an Auto Graflex 4" by 5" camera equipped with a Kodak Aero Ektar F:2.5, 178 mm lens. After being
processed, the back of the plate was painted black. For better viewing of the image, a wedged glass plate (Wiener prism) was
cemented to the emulsion side, as for old Lippmann photographs. The reproduction of human skin is remarkable realistic in a
Lippmann photograph. Also metallic reflections are accurately recorded.
Conclusions
Large-format colour reflection holograms can be recorded with rather good colour rendition. However, further improvements
are needed, e.g., as regards colour saturation, image resolution, signal-to-noise ratio, dynamic range. Employing emulsions
with a grain size less than 10 nm and four recording laser wavelengths will soon make it possible to make a holographic image
that would not be possible to distinguish from the object itself. The virtual colour image behind a holographic plate represents
the most realistic-looking image of an object that can be recorded today. This perfect 3D imaging technique has many obvious
applications, e.g., for displaying unique and expensive artefacts as well as in advertising.
Modern Lippmann photography may have limited applications in photography and colour imaging, but may very well appeal
to artists and art photographers. The Lippmann photograph is virtually impossible to copy, which makes it a unique, one of its
kind, photographic recording combined with extremely high archival stability. Since the quality of a Lippmann photograph
mainly depends on the recording material, special isochromatic ultrafine-grain emulsions are absolutely necessary in order to
record absolute correct colour photographs. The holographic plates used here are not really designed for Lippmann
photography and thus it is not possible to demonstrate the perfect quality that theoretically can be obtained with interferential
colour imaging.
13
Figure 11. Lippmann portrait of the author
References
1. E. N. Leith and J. Upatnieks, “Wavefront reconstruction with diffused illumination and three-dimensional objects,” J. Opt.
Soc. Am. 54, pp. 1295-1301, 1964.
2. S. J. Zacharovas, D. B. Ratcliffe, G. R. Skokov, S. P. Vorobiov, P. I. Kumonko, and Yu. A. Sazonov, “Recent advances in
holographic materials from Slavich,” in HOLOGRAPHY 2000, T. H. Jeong, and W. K. Sobotka, eds., Proc. SPIE 4149, pp. 73-
80, 2000.
3. M. Watanabe, T. Matsuyama, D. Kodama, and T. Hotta, “Mass-produced color graphic arts holograms,” in Practical
Holography XII, S. A. Benton, ed. Proc. SPIE 3637, pp. 204-212, 1999.
4. T. Kubota, “Recording of high quality color holograms,” Appl. Opt. 25, pp. 4141-4145, 1986.
5. H. I. Bjelkhagen, T. H. Jeong, and D. Vukièeviæ, “Color reflection holograms recorded in a ultrahigh-resolution single-layer
silver halide emulsion,” J. Imaging Sci. Technol. 40, pp. 134-146, 1996.
6. Y. Gentet and P. Gentet,“"Ultimate" emulsion and its applications: a laboratory-made silver halide emulsion of optimized
quality for monochromatic pulsed and full color holography,” in HOLOGRAPHY 2000, T. H. Jeong and W. K. Sobotka, eds.,
Proc. SPIE 4149, pp. 56-62, 2000.
7. P. M. Hubel and L. Solymar, “Color reflection holography: Theory and experiment,” Appl. Opt. 30, pp. 4190-4203, 1991.
8. M. S. Peercy and L. Hesselink, “Wavelength selection for true-color holography,” Appl. Opt. 33, pp. 6811-6817, 1994.
9. T. Kubota, E. Takabayashi, T. Kashiwagi, M. Watanabe, and K. Ueda, “Color reflection holography using four recording
wavelengths,” in Practical Holography XV and Holographic Materials VII, S. A. Benton, S. H. Stevenson, and T. J. Trout,
eds., Proc. SPIE 4296, pp. 126-133, 2001.
10. G. Lippmann, “La photographie des couleurs,” C. R. Hebd. Séances Acad. Sci. 112, pp. 274-275, 1891.
11. G. Lippmann, “La photographie des couleurs [deuxième note],” C. R. Hebd. Séances Acad. Sci. 114, pp. 961-962, 1892.
12. G. Lippmann, “Sur la théorie de la photographie des couleurs simples et composées par la méthode interférentielle,” J.
Physique 3 (3), pp. 97-107, 1894.
13. H. I. Bjelkhagen, T. H. Jeong, and R. J. Ro, “Old and modern Lippmann photography,” in Sixth Int'l Symposium on Display
Holography, T. H. Jeong, ed., Proc. SPIE 3358, pp. 72-83, 1998.
14. H. I. Bjelkhagen, “Lippmann photographs recorded in DuPont color photopolymer material,” in Practical Holography XI
and Holographic Materials III, S. A. Benton and T. J. Trout, eds., Proc. SPIE 3011, pp. 358-366, 1997.
15. H. I. Bjelkhagen, “New optical security device based on one-hundred-year-old photographic technique,” Opt. Eng. 38, pp.
55-61, 1999.
16. H. I. Bjelkhagen, “Lippmann photography: reviving an early colour process,” History of Photography 23, pp. 274-280,
1999.
-
dave battin
Suitable dyes
Years back Eugene Dolgoff showed me a hologram he made of what i would call a Bragg/hologram, full color, limited viewing angle (quite deep) ..... Almost like a combination of the two ,showing Popeye, Campbell’s soup and a bunch of other items , but the color was always perfect.
-
Martin
Suitable dyes
jean wrote:Thank you Colin for this new section.
I need to purchase dye(s) for diffusion method.
Are Pinacyanol and Cyanine suitable to make Lippmann emulsion ?
I've read a paper about and seems that Lippmann used cyanine and chinoline red.
Valenta choice Erythrosine and Ives taked Isocol (??), Erythrosine and Pinacyanol.
So, I guess that Cyanine and Pinacyanol can be used.
Jean, Cyanine used to be the red sensitizer (like Pinacyanol) back then...
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jean
Suitable dyes
Martin wrote:Jean, Cyanine used to be the red sensitizer (like Pinacyanol) back then...
Sorry, I was not enough clear.
I was thinking about 1,1 -diethyl -2,2 cyanine iodide for green sensitivity (dye used in the diffusion method)
-
Martin
Suitable dyes
jean wrote:I was thinking about 1,1 -diethyl -2,2 cyanine iodide for green sensitivity (dye used in the diffusion method)
I believe the diethyl...cyanine sensitizes within a fairly narrow wavelength range, which is good if you want to expose at 532nm but so good for Lippmann photography.