Solving Polaroid PN 55 Secret

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by Mustafa Umut Sarac, May 11, 2008.

  1. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Ron , As you remember , I had been started a thread on polaroid emulsion making here.
    Finally , you said , kodak had been secretly developed the emulsion recipes.
    50 years ago , there was not todays spectrometers and I believe PN 55 developer and thin film formulas can be reverse engineered.
    I worked 22 years on zildjian and published the secret at www.cymbalholic.com under zildjian secret thread.
    Some people visited me from France and started to cymbal business at there with my recipe.
    I think I can again make it for PN 55.
    Ron , you know the technology , how can this film and developer be analysed ?
    I read some whiskey manufacturers at Scotland started to spectrum analysis their alcohol to match all future production to a single formula.
    Liquids ...
    I did not use PN 55 but I saw some nude pictures taken by rodenstock land at polaroid com gallery and they were the best bw pictures i have ever seen.
    How Kodak test their films chemical contents ?
    Is there a special method ? Can Kodak be hired to analyse the films as Land hired the Kodak ?
    Or are there same instruments at USA elsewhere cheaper ? University labs ?
    Nowadays dollar is so low and its time to import knowledge from USA .
    I think England and Europe costs 3 times more !
    Can Russian technology be hired ? Is there anyone knows Russia ? David may be ?
    Ron , you know the patents of Land , Can you collect recipes here belong to PN 55 ? If I know some portion of the mix , it would be easier to extract unknown.
    I read Davids monobath experiments. Is Polaroid monobath formula inside of little pockets which opened and spreaded with rolls.
    I think I will start from there , is there a polaroid monobath patent just for PN 55 ?
    Is there still factory fresh PN 55 at the market ?

    Best ,

    Mustafa Umut Sarac

    Istanbul
     
  2. Alex Hawley

    Alex Hawley Member

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    Hi Mustafa,

    I can't speak for Ron, nor do I have any of his wizardy in my brain, but perhaps I can offer a couple things to the discussion. I've used several boxes of Type 55 so I have some familiarity with it.

    You're right. It is/was an absolutely excellent film. I've said many times that I could have been happy just using Type 55 for everything.

    One problem I see with reverse engineering it is with the film base material. The stuff that was used was pretty unique. It was a lot thinner yet stronger than conventional film bases. To my meager knowledge, Type 55/665 and Kodak Panatomic X were the only commercial films that used this base material. All of those films are out of commercial production so I would suspect that the base material is nearly impossible to find. Could it be reverse-engineered? I'm sure it could, but producing it would take a full-scale plastic/chemical sheet production facility.

    The second problem I see is one that Ron has wrote about before. The most difficult thing to manufacture on the instant films was the chemical pod. Not that the chemistry was hard, it was the pod itself that was very difficult to do.

    My suggestion is to experiment with monobath developers. David Goldfarb has been writing about them lately. No chemical pods required.

    You may be able to still find some retailers with a small stock of Type 55. Be prepared to spend at least $100 per box for it. I checked Polaroid's web store and they are no longer listing it.

    Type 55 and 665 were stunning films. Its a shame they are gone but that's the unfortunate reality.
     
  3. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    There are hundreds of companies at china and india which seeks customer like crazy. They can manufacture the base and the pods. At Intota site , there are many experts who are ready for help.
    But it coasts 500 dollars per hour but they have 40 years of experience.
    I think pod is the easiest thing to do but I want the image quality , we dont need to imitate the pod. May be customer distribute the monobath at home . It would be decrease the manufacturing cost also. We are not running after instant photography but the quality.
    Market is 4 x 5 . I think after the chemical analyses , Ron can change the formula with cheaper newer chemicals without altering the result.
    I am after writing a manual of inside chemicals.
    I need patent numbers exactly for PN 55. And a analyser company , may be Kodak Labs.
    Ron , can you reach inside of labs today with your connections ?
     
  4. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    2686717
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    I found 46-52 patents from land
     
  5. Murray@uptowngallery

    Murray@uptowngallery Member

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    Somewhere I read the paste had triethanolamine in it.

    But that's about as helpful as saying D-76 has water in in after it's mixed.
     
  6. usagisakana

    usagisakana Member

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    so that's what i've been doing wrong
     
  7. Jim Noel

    Jim Noel Member

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    If I remember correctly, originally the film used was Panatomic X.
     
  8. keithwms

    keithwms Member

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    Mustafa, I don't think there is any problem figuring out what's in the pods... certainly, we can break open a pod and do spectroscopy and tell you exactly what's in there and in what proportion. We probably already can guess the most important ingredients based on others' monobath work.

    Even deciding which film best approximates what was used may not be such a challenge- there are so many rumours about it being panatomic x that we could just say, fine, close enough, let's call it that. No need for me to throw it on a TEM or whatever and prove it so.

    But then what?

    The issue is the reliable production of the packed and podded film with QC at the level of Polaroid... or better yet, the level of Kodak or Fuji. Based on what reading I've done, I would conclude that getting the polaroids to shelf at reasonable cost, in mass quantities, and with acceptable shelf life and QC is by far the hardest part. The formulas have been known for a very long time by two, maybe three companies.

    What disappoints me is that polaroid has yet to step up and say, fine, we hereby discontinue the film as a packed product, but we will release the emulsion formula and the goo recipe... I mean, formulary could probably make up a goo and sell it in nothing flat, for use with a variety of films and processable by relatively simple rolling mechanisms. It disappoints me that polaroid didn't see that the true value of the product is definitely not in the positive image- it is in the quickly developable neg. For this they will face the wrath of St. Ansel himself on Judgement Day. :wink: And Ansel's gonna be pissed. I think he's going to place them on zone 20 or so.
     
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  9. Murray@uptowngallery

    Murray@uptowngallery Member

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    If the goal is to make a film that acts like 55, NOT necessarily to make an INSTANT film that acts like 55 (and the prints themselves are not what makes it so great), one needs to keep perspective.

    Do people who use and love 55 think that there is really nothing that can provide comparable results? Have the other film companies really never matched or exceeded 55's capability?

    "What is the best...?" questions pop up here daily. There is no such best ANYTHING in subjective interpretation.

    I don't think a patent or even a list of ingredients makes something manufacturable (we would be lacking the specific processes), and what incentive do people who work 9-5 have, to research this to assist film lovers on the Internet? I don't see how the time and resources can be procured for the research on a charity basis. As Mustafa noted, people ARE available for hire, but who is going to cough up the money?

    Then, how close is "close enough" in reverse chemical engineering? There are generic pharmaceuticals and cosmetic products that mimic 'name brands'. Some are functionally equivalent (speaks highly for the reverse engineering), but many have slightly different minor differences like odor, texture etc. (I'm speaking more about non-medicinal product copying).

    If the goal is to make the film only, for home development, I really have to wonder whether people shooting film in formats other than 4x5 and 8x10 suffer the indignity of feeling the film they use will never be as good as Polaroid 55.

    This sounds like more effort than even getting Polaroid to start making it again. At least that has a yes or no result that isn't subjective.
     
  10. Ray Heath

    Ray Heath Restricted Access

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    g'day all

    so the experts who made and marketed these products could not find a viable consumer base, why should any other manufacturer even bother?

    maybe it's time you all got over your attachments to various materials, good photography is not about what you use, it's about how you see

    Ray
     
  11. Dinesh

    Dinesh Subscriber

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    OT. but Zildjian cymbals were fantastic!
     
  12. Murray@uptowngallery

    Murray@uptowngallery Member

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    Mustafa, that French company, if they were successful, should have paid you for your expertise. :smile:
     
  13. Photo Engineer

    Photo Engineer Subscriber

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    I did not see this post when it went up over a month ago. I was in Montana at the Formulary.

    I can say that Kodak did develop some products for Polaroid, because even though Land was a genius at inventing, his engineers did not have production coating machines nor did they have emulsion formulas and so Kodak developed a series of products for him including some B&W and color products. I do not know which ones.

    The pod contains either KOH or NaOH as alkali along with restrainer and carboxymethyl cellulose (Unflavored Citrucel to US people :D ). There are also some developers and silver halide solvents. The film sheet is a film sheet but the reciever sheet is a special thing which forms the positive print. The whole thing is like a monobath.

    In addition, the package contains rails to keep the distribution of pod goo even over the width and length of film, and the pod has dividers to promote even spread and burst when pressure is applied.

    Filling a pod is a very exact and complex process and assmbling a pack is very expensive with some rather complex equipment involved.

    Hope this helps.

    PE
     
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  15. Murray@uptowngallery

    Murray@uptowngallery Member

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    Take a look at US Patent 3615438. It's a Polaroid patent with a lot of discussion of monobath developer recipes and various negative films (Kodak and other).

    It doesn't seem to address Type 55 specifically, but the information covers a good bit of what I think you're interested in.

    Murray
     
  16. jnanian

    jnanian Advertiser

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    pssst - still are ...
     
  17. John Shriver

    John Shriver Member

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    Polaroid T-55 data sheet is still available here:

    http://www.polaroid.com/service/filmdatasheets/4_5/55fds.pdf

    You want a fine grain film with a similar HD curve.

    Of Kodak films presently available, it looks a lot like Tri-X Pan Professional (TXP320). Long toe, long straight line section, no shoulder. Very much like the classic (but discontinued) portrait films like Ektapan and Royal Pan. Or even like Verichrome Pan.

    Ilford's Delta 100 is very straight line, no shoulder, but but as much toe.
     
  18. Photo Engineer

    Photo Engineer Subscriber

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    The Polaroid film shown has poor red sensitivity and almost resembles a Tungsten film in speed distribution. The dmax is very low and the latitude only covers about 1/2 of that seen in most modern films.

    Try here: http://kodak.com/global/en/professional/support/techPubs/f4016/f4016.pdf?id=0.2.26.14.17.16.14&lc=en

    About half way down the page they show the technical specifications of a typical Kodak B&W film and you see that this film has about 2x the latitude and a lot more red sensitivity. This is typical of Kodak films and is quite different than the T-55 data in the Polaroid link.

    PE
     
  19. John Shriver

    John Shriver Member

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    The MTF falls off impressively fast on T-55.

    The sensitivity curve of another film could be adjusted by a color balancing filter, like a blue one meant for shooting daylight film under tungsten light.
     
  20. Photo Engineer

    Photo Engineer Subscriber

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    Yes, that MTF has been what makes me suspect it was none of the earlier Kodak emulsions. IIRC, they were better, unless the MTF was ruined by something done in coating, again something Kodak would not do.

    PE
     
  21. keithwms

    keithwms Member

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    Well, how would one measure MTF in the case of T55? Seems to me the most honest way to do it would be to shoot a chart, pod-process the sheet and then take measurements off the cleared neg. Is that what they'd do? If so, then it seems to me that this could account for some deviations between T55 and panatomic x. I would expect pod processing to introduce a sort of Gaussian falloff in MTF simply because of the way the components mix and are distributed. Only the centermost regions of the film see truly optimal development, I'd suspect.

    Make any sense?
     
  22. Photo Engineer

    Photo Engineer Subscriber

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    Keith;

    Yes, that is the way it would be done, but it would be done the same way in both the Polaroid film and regular film. The processing is forced on it by the desire for instant film. So, if one used D76 for example, I would guess you would get a different MTF.

    PE
     
  23. Philip Jackson

    Philip Jackson Member

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    The quoted resolution of Polaroid Type 55 of 160-180 line pairs/mm (negative) probably indicates an emulsion optimised for this purpose. The relatively poor print sharpness of 20-25 line pairs/mm is caused by “sideways image spread” during diffusion (a thin layer of developer separates the negative and print, which are not in perfect contact). The spectral sensitivity may reflect the fact that Polaroid Type 55 was introduced in 1961 and has probably remained exactly the same ever since. Polaroid’s first panchromatic film came out in 1955, so their knowledge of dye sensitization in 1961 may not have been cutting edge. The relatively low negative Dmax may reflect the migration of silver to the print.

    I only ever used Type 665 (the smaller pack film size) a few times, because of the cost, and because the one stop difference between a satisfactory negative and print seemed annoying. I cynically wondered why Polaroid hadn’t re-developed Type 55 to remove this discrepancy. However, Land published a graph of an early trial with a five stop difference, so it was probably an extraordinary accomplishment to get the difference down to only one stop. (The white powder from a spilled sodium sulfite solution in the car was a further annoyance, which encouraged me only ever to take water into the field, and leave full clearing until I got home).

    I suspect most Type 55 is exposed for the negative, and as previously suggested it would be far easier to work out a portable monobath process for a specific commercially manufactured black and white film, rather than attempt to re-engineer an exact replica of Type 55. Conventional cameras could then continue to be used, and there would be no need to emulate Polaroid pack film manufacture.

    The Kodak Bimat web processing process, which was intended for conventional negative materials, is worth considering in this context (see Grant Haist, Modern Photographic Processing, New York: Wiley, 1979, vol. 2, pp. 397-399). Basically, a strip of photographic film base was coated with a polymer or gelatin layer presoaked with a special monobath processing solution. This moist film was then brought into contact with conventionally exposed film. Negative development was complete in one minute, though four minutes were required to transfer a positive to the web film. Although the results were relatively stable, additional fixation and washing may have been required within ten days for archival permanence. Kodak originally developed Bimat for Cold War military reconnaissance applications in about 1960 (Tregillus et al. US patent 3179517), and it was later declassified and used in the unmanned Lunar Orbiter photographic missions which surveyed the moon for landing sites (see http://www.lpi.usra.edu/resources/lunar_orbiter/book/introduction.shtml).

    Haist cites the following formula (from Tregillus) as useful for imbibing into the absorbent layer of the web:

    2,2’-Iminodiethanol-sulfur dioxide
    addition compound (20 mole percent S02) 190.0 g
    Hydroquinone 11.6 g
    4,4-Dimethyl-l-phenyl-3-pyrazolidone 1.0 g
    Sodium thiosulfate, desiccated 5.4 g
    Potassium iodide 0.42 g
    Water to make 1.0 liter

    The second developing agent appears to be a phenidone, probably dimezone-S. The amine-sulfur dioxide addition product serves as both an alkali and as a preservative. Perhaps triethanolamine (TEA) or a more conventional preservative-alkali system could be substituted. There may have been additional physical development nuclei added to the “receiver” for the positive image. The principle behind diffusion transfer resembles reversal processing in that there is both a positive and negative present in the developed silver halide emulsion layer; it is the unexposed silver halides (representing the positive image) that are dissolved and transferred to the image-receiving light-insensitive second support.

    In his chapter on monobaths, Haist (p. 187) cites an apparently related formula for a thickened monobath (US Patent 3,392,019, by John C. Barnes and Gerald J. Johnston of Kodak):

    Methylaminoethanol-sulfur dioxide
    addition product (17.8 SO2) 75.0 g
    l-Phenyl-4,4-dimethyl-3-pyrazolidone 2.0 g
    Hydroquinone 10.0 g
    Sodium thiosulphate crystals (5 H20) 50.0 g
    Potassium iodide 0.5 g
    pH 10.5
    Water to make 1.0 liter
    Colloidal silver (Carey Lea Silver) 0.2 g
    Natrosol (hydroxyethycellulose) 0.2 g
    (Hercules, Inc.)

    The colloidal silver provides physical development nuclei, allowing a lower thiosulphate concentration, and prevents excessive fog. Unfortunately the colloidal silver and amine product put this formula out of standard home developer mix capabilities, although somebody may be able to suggest a relatively straightforward method of preparing the required amount of colloidal silver from a silver nitrate solution. The thickening agent can be a water soluble polymer or gum, methylcellulose, silica gel, starch, etc.

    Processing involved applying this thickened solution to the surface of an emulsion. It was allowed to stand for 10 min at 70 degrees F before being rinsed away to exhibit a very high quality, completely developed and fixed image. Photographic speed, contrast, granularity, and acutance were said to be equal to those produced when the film was developed in the normal way in D-76, followed by separate fixation. Imagine a pod in special film envelope, or squeezing a bead of this stuff out of a tube (a new product line for Photographer’s Formulary?), rolling it over sheet film (or a short length of roll film), and then rinsing it off. Monobaths require much less washing than conventional fixation, but an additional processing step might be required to get rid of the antihalation backing.

    For prints, perhaps it might be more appropriate to revive a basic diffusion transfer process. Image transfer is popular with Polaroid colour materials, but apparently does not work with the current Polaroid black and white products. In this case, it may be worth trying an alternative procedure with other black and white emulsions. Edwin H. Land, in his paper ‘The Universe of One-Step Photography’ in Pioneers of Photography: Their Achievements in Science and Technology, edited by Eugene Ostroff (Springfield, Va.: SPSE, The Society for Imaging Science and Technology, 1987, pp. 219-248), describes and reproduces some of his first experiments carried out in March 1944:

    “The film was Kodak Contrast Process Ortho. The developer was D-8 with some hypo added to it. The esoteric material used for image-receiving was either a sheet of blotting paper or a sheet of filter paper. Nothing was done to it beforehand. It was wet with developer. Next we put this wet sheet of filter paper down on a Plexiglas sheet, took the film, which had been exposed in the camera, rolled it against the filter paper, and left it there for about a minute. At the end of the minute we peeled it off, and what we had was a negative and a black-and-white positive image on the filter paper” (p.219)

    Plate 1a, p.233, reproduces one of these images deposited in alpha-cellulose, which doesn’t look too bad, except for a few flecks of coarse paper grain. Plate 1b, a more conventional looking glossy image, was produced on opal acetate, with the surface hydrolysed to regenerate it to cellulose. Both of these were subsequently washed. Plate 1c is a transfer to a negative emulsion which had been fixed out, leaving silver nuclei as very fine particles within the gelatin. This image is a strong sepia color. Although Land subsequently went to a lot of trouble to get neutral toned images, sepia is now perfectly acceptable again, and if you relax Land’s requirement that the prints be dry and archival as soon as they come out of the camera, home brew Polaroid might be practicable.

    My initial attempt, following these sketchy instructions, using a roller, some cheap cartridge paper, lith film, D-8 and increasing amounts of hypo, failed. I wondered if the amount of sodium thiosulfate required is a critical factor, and for my second attempt I re-started with the following formula from Land’s US patent 2,543,181:

    Sodium sulfite (anhydrous) 9 g
    Hydroquinone 4.5 g
    Sodium hydroxide 3.75 g
    Potassium bromide 3 g
    Sodium thiosulfate 10 g
    Water to make 170 cc

    This is very roughly equivalent to D-8 diluted 1 + 1 with about 60 g/litre sodium thiosulfate. I reduced the quantities to 100 ml which was sufficient for 4 x 5 inch paper in a small flat bottomed tray.

    Once again I still couldn’t get anything but smudges on ordinary paper, but I was able to get brown positive images on fixed-out photographic paper. The paper was soaked in the developer, placed in a large empty flat bottomed plastic container. A sheet of exposed film was slapped onto it and left for a minute or two. Kodak Professional Copy and Tri-X Ortho didn’t seem to work as well as the generic lith film, so I didn’t persist with them (I suspect they may require significantly different exposure and development times). I haven’t tried photographic paper as the negative material. They may work, but I suspect it may be easier to mobilise the silver in lith film. The amount of hypo in the developer is not sufficient to fix the film to completion (as in a monobath), so if you want to try and salvage or inspect the negative you need to separately fix it. The print seems to need at least a water rinse to get some of the highly alkaline developer off it. The colloidal silver particles that make up the image are very delicate and can be easily wiped off, so handle with care. Fixer may also be advisable to neutralise the developer and better stabilise the print. According to Haist, the main neutralising chemical in Polaroid coater swabs is ammonia, but I’d rather not have a an open tray of it in the darkroom.

    For my next batch of developer, I added 5ml of glycerol/glycerin to 100ml of developer in an attempt to improve the contact between the developer and the positive. However this didn’t work at all, presumably because the quantity was too great to ensure satisfactory contact for diffusion. Subsequent investigation suggests there is nothing inherently wrong with glycerin in the right quantity: United States Patent 3645731 (Agfa-Gevaert researchers, 1970) claims increased stability of diffusion transfer activator baths with trisodium phosphate and polyalcohols (glycerol being particularly suitable) in quantities preferably between 15 and 30 ml. per liter.

    In my next session I had trouble getting the exposure and development right. The Image color was relatively neutral to start with, but then went reddish once I added a drop of glycerin. This may have coincided with exhaustion of the hydroquinone (see attached image; in some cases I held detail in the white dress but the doll's face seemed to be solarised).

    Incidentally, Land seems to have experimented with some very exotic developers for his pods. It didn’t matter to him that these developing agents oxidised rapidly, as the pod excluded air until it was broken for processing, and then the developer was rapidly spread between the negative and the print, before the air could have much effect. One of his patents mentions mixing these developers in a nitrogen atmosphere, which raises questions regarding manufacturing costs and practicality.

    The receiving paper doesn’t necessarily have to be fixed out photographic paper or film. Land discusses sodium sulphide and heavy metal salts like lead as silver precipitating nuclei on the receiving sheet, but colloidal silver may be preferable in the home darkroom. I haven’t found a clear, simple and practical description of Carey Lea’s dextrin method of preparing colloidal silver, in which a solution of silver nitrate is gradually added to a solution of sodium hydroxide and starch. The precipitate is then allowed to settle, and the liquid poured off, possibly after alcohol is added. If you could calculate the right quantities, you might to be able to mix a stock solution which could go directly into the Barnes and Johnston thickened monobath formula above, or a 1% gelatin solution for coating on paper. Example 1 in US patent 4888267 gives a similar but far more complex procedure, with completely unrealistic quantities.

    My first attempt to make an alternative form of colloidal silver was a failure. Following B.H. Carroll et al.’s The Photographic Emulsion (1968), p. 142: “Colloidal silver sulphide was prepared by adding first 2.34. ml of 0.107 M Na2S2O3 [i.e. 24.8 g/litre sodium thiosulfate], then 5.0 ml of 0.100 M AgN03 [i.e. 17 g/litre silver nitrate] to 170 ml of warm 1 per cent gelatin solution; the mixture was allowed to stand about an hour before use to complete the decomposition of the silver thiosulphate.” I made a mistake scaling the quantities and the colloidal silver/gelatin coating is too dark on the paper. On soaking in developer, the emulsion seems to be stable, although it immediately fogged exposed film. Perhaps the correct quantities may well work, although I might give it a rest for awhile.

    Perhaps this long message might encourage other experimenters to explore some of the possibilities, hopefully without necessarily having to prepare your own film from scratch yet. However preparing your own emulsion could be an advantage as you could control silver content and hardening, pick your own image size, and use a paper base rather than glass, acetate or polyester. Or maybe you could make silver gelatin ambrotypes on black anodized aluminium, develop them in a monobath paste in your dark tent, and be a step ahead of the wet plate crowd!
     

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  24. Photo Engineer

    Photo Engineer Subscriber

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    You don't mention this in your experiments, but all Polaroid and Kodak products that use diffusion transfer (except for Bimat) used a set of rails on each side to insure the proper amount of developer or activator is applied to the sandwich. If you don't do this, you chance getting streaks or no image at all.

    Land did his initial work using the methods you describe, using conventional camera products but using a prepared reciever sheet. The goo was pH 12 or so in the final product. This agrees more with your last formula example. He used carboxy methyl cellulose in some of his work. Kodak used it in all of their DT products.

    The above phenidone analog is not Dimezone-S. Dimezone S has a hydroxy methyl group replacing one of the methyl groups. It is more active, more soluable and more stable.

    PE
     
  25. dwross

    dwross Subscriber

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    Philip:

    Great post! I'll have to read it a few more times for all the info to soak in and through, but that's the fun part. If your doll is any indication, you're onto something. I hope you keep after it. There are many overlapping puzzles involved. Land had a team. Hopefully, you'll have others join your efforts. Thank you.

    d
     
  26. Kirk Keyes

    Kirk Keyes Member

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    Jun 17, 2004
    Location:
    Portland, OR
    Shooter:
    4x5 Format
    "Unfortunately the colloidal silver and amine product put this formula out of standard home developer mix capabilities, although somebody may be able to suggest a relatively straightforward method of preparing the required amount of colloidal silver from a silver nitrate solution."

    Here's a nice, vintage report on colloidal silver and it's preparation by Carey Lea himself:
    http://books.google.com/books?id=K5MOAAAAIAAJ&pg=PA337&dq=carey+lea+allotropic+silver#PPA337,M1

    And another one from the same era with more details:
    http://books.google.com/books?id=zZMUAAAAYAAJ&pg=PA282&dq=carey+lea+allotropic+silver