New life of old idea

This is a forum exploring Lippmann photography.
Locked
Sogokon'A

New life of old idea

Post by Sogokon'A » Sat Nov 29, 2008 4:43 pm

I wish to break silence. Give let us recall very old and well the forgotten method of a color photography. It is a question about autochrome photo process which has invented by Alpheus Hyatt Verril in 1902. The essence of the method consists that on positive black-and-white emulsion the mask from the painted grains of starch which acted as filters is put
http:// home.bway.net/jscruggs/auto.html.
Let's apply this method to Lippmann’s photography, i.e. we shall arrange the mosaic RGB-filter between a substrate and emulsion (Pic.1).
PIC1A.JPG
PIC1A.JPG (28.95 KiB) Viewed 6954 times
The greatest difficulties for the Lippmann’s method are represented with transfer low saturation colors close to white. It is connected with small coherent length of broadband color signals. The information on color tone is stored in the form of autocorrelation function and concentrated near to a surface of a layer. The slightest defects on a surface or shifting, lead to greater distortions in a colors rendition. Application of filters essentially increases quantity isophase planes and the information on color is distributed on all thickness of the layer. But it is necessary to pay for this advantage reduction of resolution of the obtained image.
The best place for the filter is a sublayer. On thin, well hardened the layer it is possible by means of the jet printer (or a different way, for example, silk-screen printings) to put the mosaic RGB-filter. And then put emulsion. It is possible also on a transparent film to print the mosaic filter, to paste it to a substrate and put emulsion.
Considering, that Lippmann’s emulsion has much greater thickness, than photographic, applied in autochrome process, it is possible to try some grain of starch (and it is better, any painted polymer, with a refraction index equal to RI gelatin) to arrange directly in the emulsion layer (Pic.2).
PIC1C.JPG
PIC1C.JPG (38.22 KiB) Viewed 6954 times
For the beginning it is possible to try a powder for the color copier.
It is necessary to notice, that contrast interference pictures increases in any case, is not dependent on where there is a grain-filter. In places of overlapping of two filters the complementary color is recording, that also promotes accuracy of transfer of complex light tones.
Thus, association of two ancient ways with use of modern technologies can give unexpectedly good result.
All told above is fair and for color holography. I have considered this opportunity and have described in a Russian-speaking part of a forum few days ago.

Sergio

New life of old idea

Post by Sergio » Sat Nov 29, 2008 10:31 pm

Thank you for you posting, this is interesting!

For printing systems microcapsules preparation can be made at the desired sizes and colour by emulsification procedures for sure, (The procedure that I know is about yellow, magenta and cyan capsules; what about it?) with mixed density, after imaging and "developing" the hologram or Lippmann structure the dye colour capsules can be made transparent with an adequate UV exposure, such emulsion mixing and coating is perfectly possible, but what are the advantages to a dot printing system or a master system this method over conventional holography?

Martin

New life of old idea

Post by Martin » Sun Nov 30, 2008 12:15 pm

This is an interesting approach. I was aware of the Lumière brothers' system. But I never heard of Verrill.

I wonder about the nature of the dyes in your color filter. Wouldn't it be required to have particular dyes to provide a relatively well defined (wavelength) area of absorption?

Sogokon'A

New life of old idea

Post by Sogokon'A » Sun Nov 30, 2008 2:21 pm

Sergio wrote:Thank you for you posting, this is interesting!
For printing systems microcapsules preparation can be made at the desired sizes and colour by emulsification procedures for sure, (The procedure that I know is about yellow, magenta and cyan capsules; what about it?) with mixed density, after imaging and "developing" the hologram or Lippmann structure the dye colour capsules can be made transparent with an adequate UV exposure, such emulsion mixing and coating is perfectly possible
Thanks, Sergio, this is very good continuation!
Lippmann’s photography is an amazing thing. Within the limits of a passband of each (any) filter the exact copy of a color signal will be written down and reproduced. Therefore it is absolutely not important, on what basis decomposition, on RGB or CMY will be executed. Even most simple blue-yellow (BY) division will be fine to work. If you have an opportunity to put it into practice - safely try. If will experiment take more than complex colors: brown, crimson, lilac, orange, violet, beige, etc. In this case advantages of this method will as much as possible are shown.
Sergio wrote: but what are the advantages to a dot printing system or a master system this method over conventional holography?
Here two questions.
1. Whether it is possible to use system CMY for color holography? Yes, it is possible, as in the sum these three colors give white light. Moreover, at such system of filters it is possible to use four lasers: blue, cyan, yellow and red.
2. Whether decolouration of filters will be useful at registration of usual holograms?
With confidence I can not tell, experiment is necessary. More likely "yes", than "is not present".

Sogokon'A

New life of old idea

Post by Sogokon'A » Mon Dec 01, 2008 9:02 pm

Martin wrote:This is an interesting approach. I was aware of the Lumière brothers' system. But I never heard of Verrill.

I wonder about the nature of the dyes in your color filter. Wouldn't it be required to have particular dyes to provide a relatively well defined (wavelength) area of absorption?
I too knew that brothers Lumière have received the patent in 1903. But here http://ru.wikipedia.org/wiki/Веррил,_Алфеусt here is a speech about 1902.

For check of idea the mode of «the minimal working capacity» is sufficient. Therefore it is possible to use the same dyes which were used by brothers Lumière. And then it is methodical, step by step to improve this system.

Martin

New life of old idea

Post by Martin » Wed Dec 03, 2008 10:24 am

Sogokon'A wrote:I too knew that brothers Lumière have received the patent in 1903. But here http://ru.wikipedia.org/wiki/Веррил,_Алфеусt here is a speech about 1902.

For check of idea the mode of «the minimal working capacity» is sufficient. Therefore it is possible to use the same dyes which were used by brothers Lumière. And then it is methodical, step by step to improve this system.
Meanwhile I made a search on autochromes. I was able to locate the Lumière brothers' US patent 822532 (didn't find the French patent, FR 339223, 1903). By the way, it looks though that R. Namias may equally be among the inventors of this technique.

The patent does not mention what kind of dyes are to be used. I would assume these dyes need to be carefully adjusted to the laser wavelengths.

Another issue may be the size of the starch particles. According to a publication on the Lumière brothers' invention (Comptes Rendus, May 1904) these particles have a size of 15-20nm. This might already be too large for blue light - leading to excessive scatter – particularly when there is a mismatch with the refractive index of the matrix material.

Sogokon'A

New life of old idea

Post by Sogokon'A » Wed Dec 03, 2008 3:10 pm

Martin wrote:Meanwhile I made a search on autochromes. I was able to locate the Lumière brothers' US patent 822532 (didn't find the French patent, FR 339223, 1903). By the way, it looks though that R. Namias may equally be among the inventors of this technique.
I have once again re-read this note in wiki. I wished to find its author. Its father Edison Emeri Verrill, the known zoologist has paid attention that. Probably, idea autochrome process the structure of a retina of an eye of animals or human has prompted them. But in the environment of biologists this idea could not be adequately estimated, and could not receive development. And in memoirs could be quite fixed.
Martin wrote:The patent does not mention what kind of dyes are to be used. I would assume these dyes need to be carefully adjusted to the laser wavelengths.
I agree with it if it is a question of holography. At exposing by white light it is possible to choose any convenient dyes, it is possible in view of spectral sensitivity emulsion.
Martin wrote:Another issue may be the size of the starch particles. According to a publication on the Lumière brothers' invention (Comptes Rendus, May 1904) these particles have a size of 15-20nm. This might already be too large for blue light - leading to excessive scatter – particularly when there is a mismatch with the refractive index of the matrix material.
_00007a.JPG
_00007a.JPG (34.83 KiB) Viewed 6842 times
Here a photo of the grains of corn starch increased in 300 time and a powder of the color copier. Grains of starch have the spherical form and are painted diamond green. Grains of a powder have the wrong form and on the size coincide with the fineest fraction of starch. The characteristic size of 8-12 micrometers. It is necessary to search for something fineer.

Ed Wesly

New life of old idea

Post by Ed Wesly » Wed Dec 03, 2008 7:18 pm

Martin wrote:
According to a publication on the Lumière brothers' invention (Comptes Rendus, May 1904) these particles have a size of 15-20nm.
I see this dimension quite often, and it must be off by a metric prefix.

I am holding an Autochrome plate in my hand with a transparent ruler on top of it, with one of my non-grey hairs sandwiched between the two, observing with a 8X magnifying glass, and the grains are more like on the order of a diameter of the hair, 25 to 50 microns rather than nanometers. I can almost resolve them with my myopic eyes!

How could they have measured something smaller than a wavelength of light in 1904? Maybe they were talking about the light sensitve crystals, but then those Autochromes would have been really slow!

Great website with lots of Autochrome images: http://photographymuseum.com/exhibitstart.html My favorite is the one with the Victrola!

Martin

New life of old idea

Post by Martin » Thu Dec 04, 2008 12:26 pm

Ed Wesly wrote:I am holding an Autochrome plate in my hand with a transparent ruler on top of it, with one of my non-grey hairs sandwiched between the two, observing with a 8X magnifying glass, and the grains are more like on the order of a diameter of the hair, 25 to 50 microns rather than nanometers. I can almost resolve them with my myopic eyes!
I agree sizes in the um-range will make more sense.
Ed Wesly wrote:How could they have measured something smaller than a wavelength of light in 1904? Maybe they were talking about the light sensitve crystals, but then those Autochromes would have been really slow!
I really don't know about the autochromes.
As to measuring the grain size of Lippmann emulsions, Neuhauss seemed to have done some practical research in that direction. Armed with a microscope (4000x magnification), Neuhauss examined the structures of the interference fringes (Zenker's laminae).
Of course that magnification was insufficient to observe the tiny AgX grains but it was good enough to observe the Zenker laminae.
Ed Wesly wrote:Great website with lots of Autochrome images: http://photographymuseum.com/exhibitstart.html My favorite is the one with the Victrola!
Thanks for that link.

Locked