Capstaff's two-colour Kodachrome process.

[johnielvis]

hey--looks like them edwal toners are real toners after all--suitable for film (they say for movie film)....I checked the msds for the blue toner and it has silver reacting chemicals in there, so it's working on the silver--which is what we want---so I'm a gonna try them out....hopefully soon...

 

[johnielvis]

no success yet with edwal toners--they are obviously not powerful enough in their bleaching action to get to the heavy silver content of the film (reversal tri-x)...

hell I took some regular tri x--no fix no reversal at all..just developed to black...the bleach doesn't seem to do anything to it....must use STRONGER bleaching then....looks like best is 2 step--bleach to silver ferrocyanide then dye that....the problem is bleaching...they show that you should put acetic acid for the bleachign--tried that with vinegar and it doesn't seem to help (edwal suggest adding acetic to speed up the process)...this stuff is too weak---I want tone to completion, so I need the quickest acting and most uncontrollable dye toning process there is...all the formulae for paper seem to be way too weak and designed to be slow so you can watch it and get it before it goes too far...I WANT it to go too far....back to the sink...

 

[Photo Engineer]

Friedman's book gives several pages of toner formulas for making color images.

PE

 

[Athiril]

no success yet with edwal toners--they are obviously not powerful enough in their bleaching action to get to the heavy silver content of the film (reversal tri-x)...

hell I took some regular tri x--no fix no reversal at all..just developed to black...the bleach doesn't seem to do anything to it....must use STRONGER bleaching then....looks like best is 2 step--bleach to silver ferrocyanide then dye that....the problem is bleaching...they show that you should put acetic acid for the bleachign--tried that with vinegar and it doesn't seem to help (edwal suggest adding acetic to speed up the process)...this stuff is too weak---I want tone to completion, so I need the quickest acting and most uncontrollable dye toning process there is...all the formulae for paper seem to be way too weak and designed to be slow so you can watch it and get it before it goes too far...I WANT it to go too far....back to the sink...

When you say you're going to make a stronger bleach... do NOT use any kind of strong acid with ferrocyanide, or ferricyanide for that matter, or Elvis will be leaving the building.

 

[holmburgers]

*gulp*

 

[johnielvis]

well--the stronger bleaches really "reduced " my image--so that's not the answer either--so what probably needs to happen is to put it in the toner...take it out and rinse away the stuff in the highlights...the put it back in AGAIN...and keep building it up...I've seen mention of this "build it up" procedure--so this must be necessary.

i''m ordering the formulary straight direct toners anyways just to see what they can do...

 

[holmburgers]

If I may humbly opine, this is getting away from Capstaff Kodachrome... just a hair.

I think the defining attribute of the process is the use of dyes having the appropriate color. That's what's responsible for the look.

By messing with toners you certainly might get something, and I think it's worth pursuing, but it's going to be a fundamentally different process and will probably look quite a bit different.

Let us have a look at your colors once you figure this out.

 

[johnielvis]

capstaff??

no you misunderstand--I'm after simple color portraits--this capstaff method showed that it's possible with 2 colors..3 colors you can't put together--synthize--without a mirror of some kind..the 2 you can just put 2 sheets together--simple--and a 2 color camera is mucho simpler than a 3 color.

so I'm only trying to get a 2 color system working--I doubt anyone would be able to replicate capstaff--who know WHAT he used exactly--no point in trying to guess...best to guess at something similar with the materials that you have at hand.

and any 2 color can work--and maybe bETTER than capstaff's choice--first thing is to see what you can work with--so I gotta find what red and green I get...THEN you figure out the exposure and filtration for the balance and that's it...that's the easy part--the hard part is getting a repeatable color toning process...get that and the rest is just matching and fine tuning.

so the first thing is to see what can be toned...so that's what I'm a doing...

lemme tell you....it AINT easy.....but when I get it, then it's done for good...

 

[holmburgers]

I understand, but the thread is called Capstaff's Two-Colour Kodachrome Process.

However, I'm not trying to be a pedant; figuring out a new and novel process is awesome. I just think we should create threads that suit the discussion. All this talk of toning in the Capstaff thread just doesn't compute somehow, and I think it's misleading if someone were to jump in on it. Not to mention, your work on color toning is now buried where others might not be able to find it if they're looking for it.

Threads can go awry, that's all I'm saying I guess. Sorry for being curmudgeonly...

Now, as for your comment, "who know WHAT he used exactly--no point in trying to guess...". Well, I guess that would be one goal of this thread.

 

[johnielvis]

I guess it's all in how you define the process....hell--I think any 2 color direct positive is "capstaff"..you want the eXACT colors...I just define it more broadly. the plates used aren't availabel either, so it's like totally p0intless to define capstaff in terms of the original materials being exactly alike. anyways...while waiting for the formulary toners I'm thinking that the dmax that looks good in black and white is way too much for color--particulary if TWO will be sandwiched together....so bleaching is in order to reduce the dmax to something more managable (and tonable). Or a thinner emulsion must be used---like hologram plates---I'm REALLY going to have to buy some to experiment in a regular camera with regular developers now...the hologram FILMS that is...see how fast they can perform...

 

[holmburgers]

It's not about the materials being exactly alike, that doesn't matter. What does matter is recognizing that Capstaff's procedure is always a 2-color process, but a 2-color process is not always the Capstaff procedure... that's all I guess.

At any rate, I think what you're talking about is interesting and by all means you should carry on! oliceman:

The hologram films/plates do offer a unique advantage, admittedly, being the only emulsions that are both transparent and sensitized to only red or green. This can make an easy bipack; just pop a yellow filter on and voila. That is brilliant. I guess I wasn't thinking about how to get the separations as much as what to do with them once we had them.

This probably isn't practicable, but how about this for a bipack?... 3 different elements, sandwiched together behind the lens in this order; a film coated with liquid light, a very thin yellow acetate sheet, and a sheet of ortho film. You'd get a blue record and a green record. Or substitute the yellow acetate for red, and the ortho for panchro; you get blue and red records.

 

[johnielvis]

for portraits I think three sheets would work just fine---particularly if you exploit some lenses with chromatic abberation--yo know...the blue focuses before the red--so maybe a portrait camera using a regular mensicus but that meniscus would have the chromatic abberation corrected by the film placement...and then you get a regular spherical abberation portrait lens---can actually do all 3 colors that way in the tripack.

but up close with longer lenses...with people portraits, I don't think that the focus erors from film thicknesses will be a problem--hell--the 11x14's I shoot I know must sag considerably..and it don't ruin portraits.

 

[falotico]

I've only recently come across this thread and was interested in the discussion of the so-called "pinatype" dyes. Unfortunately, the 1911 article which discusses the dyes does not use modern nomenclature, so other than dyes with classic names such as eosin, it is very difficult to determine which dyes were tested. Capstaff in his original patent, US 1196080, describes the dyes as "acid (preferably the salt of a sulfonic acid)". As near as I can tell the dyes in the Kodak dye transfer method, Acid blue 45, Acid red 80, and Acid Yellow 11, all have a sulfate group and are acid dyes. Therefore they might fit the requirements of Capstaff's patent. It is logical that dyes suitable for relief matrices would also work with planographic matrices.

The Capstaff patent, however, mentions one critical step necessary for a planographic matrix: the gelatin must be dried out before being immersed in the dye bath. As a side-note, the original processing for the Godowsky and Mannes dye-coupler Kodachrome required that the film be dried out thoroughly before being immersed in the bleach bath. This allowed the controlled diffusion of the bleach into just the outer, (yellow), or outer two, (yellow and magenta) layers. Godowsky and Mannes might have been familiar with the Capstaff process before inventing their controlled diffusion bleach system.

 

[falotico]

Pinatype dyes

I've only recently come across this thread and was interested in the discussion of the so-called "pinatype" dyes. Unfortunately, the 1911 article which discusses the dyes does not use modern nomenclature, so other than dyes with classic names such as eosin, it is very difficult to determine which dyes were tested. Capstaff in his original patent, US 1196080, describes the dyes as "acid (preferably the salt of a sulfonic acid)". As near as I can tell the dyes in the Kodak dye transfer method, Acid blue 45, Acid red 80, and Acid Yellow 11, all have a sulfate group and are acid dyes. Therefore they might fit the requirements of Capstaff's patent. It is logical that dyes suitable for relief matrices would also work with planographic matrices.

The Capstaff patent, however, mentions one critical step necessary for a planographic matrix: the gelatin must be dried out before being immersed in the dye bath. As a side-note, the original processing for the Godowsky and Mannes dye-coupler Kodachrome required that the film be dried out thoroughly before being immersed in the bleach bath. This allowed the controlled diffusion of the bleach into just the outer, (yellow), or outer two, (yellow and magenta) layers. Godowsky and Mannes might have been familiar with the Capstaff process before inventing their controlled diffusion bleach system.

 

[falotico]

More on Pinatype dyes

Apologies for double-posting the previous text. Friedman in "History of Color Photography" in the first two pages of Chapter 26 gives a good discussion of pinatype dyes; he even addresses the 1911 article from Brit. J. Phot. vol. 58. He mentions specifically the natural dye carmine, among other types, and he gives a broad discussion of the chemistry of suitable dyes.

In particular "sulphonic groups", (which I take for "SO3" groups), caused the dye to stay in the gelatin; while "nitro groups" (NO2) caused the dye to wash out easily. It seems likely that many azo dyes with a SO3 group could be good candidates for pinatype dyes.

 

[Photo Engineer]

You may have missed this but the terminology is connected to the Pina Cryptol family of dyes. It has been found that more than one SO3- group is useful in making the dye fast in gelatin and even mordants are used.

The archetype dyes of this nature today are the Solantine class (Solantine Pink and Solantine Yellow) and then there is my old favorite Chicago Blue. A mix of the pink and yellow will probably satisfy the Capstaf short wavelength dye, and Chicago Blue itself will supply the long wavelength dye.

The PINA designation is no longer used.

PE

 

[falotico]

Acid dyes

I assume that these are the same dyes that you recommend for the dye bleach color emulsion described on page 171 of your book, "Photographic Emulsion Making, Coating and Testing".

Looking at internet images of the structures, Solantine Yellow (C.I. 13950) appears to be an azo dye with two SO3 groups; Solantine Pink (C.I. 25380) appears to be a diazo with four SO3 groups and two aniline groups. The dye called Chicago Blue appears to refer to two structures, Chicago Blue 4b and Chicago Sky Blue. From what I can tell it also has azo groups with four SO3 groups. I can't find a C.I. number for Chicago Blue. All this is consistent with acid dyes which can be reduced and made colorless in the dye bleach process outlined.


Their diffusion properties are interesting. Do they stain untanned gelatin and not tanned gelatin? Has anyone tried staining a dry gelatin tanned matrix? Could the diffusion rate be regulated by Ph?


It is surprising to see the great interest people have shown in Capstaff's two color photography. Incidentally, I am looking forward to getting volume two of "Photographic Emulsion Making" and learn more about color emulsions. I hope you're not being threatened with being chained in the barn until you finish writing it.

 

[Photo Engineer]

These dyes would probably work well for both Dye Bleach and Dye Transfer. However, Solantine Pink is a bit short as is Chicago Blue, but I have made good DB coatings with all 3 and reasonably good images. That is why I think that if they transfer, they would work well with a 2 color process. You need an orange and a blue approximation.

They are similar to DT dyes, and should transfer once the emulsion is tanned. I'm not sure though.

I am still looking at options. The barn and chains or another book. With one, I would hop I get fed, I know I have a "room". With the other I have to pay for my own keep. Decisions, decisions!

PE

PE

 

[falotico]

Well, I'm certainly looking forward to another book. In the Technicolor DT process the dye solutions were loaded with acetic acid, but the Capstaff patents don't mention this. Neither does Capstaff mention temperature, although this was critical in Technicolor DT.

 

[Photo Engineer]

I suggest experimentation.

PE

 

[holmburgers]

Thanks falotico for bringing this topic back up. It's very interesting about Mannes/Godowsky and drying the film before the diffusion process. That's an interesting point...

I think the strength of the Capstaff process is in the dye colors. I've seen them and I don't think that a mixture of typical CMY dyes would really do the trick. Of course you can make any color (in theory) with CMY, but in dye-imbitition systems the dyes cannot be mixed and expected to give a neutral scale since each dye's contrast curve is related to its own particular pH. So although you could match the color with a mixture of CMY; a mixture probably wouldn't work in the process.

So the trick is to find 2 dyes, with the right "pina" properties and the right colors. An experienced colorist could probably look at examples of the two dyed members of a 2-Color KR and give some suggestions for acid dyes that may work.

 

[Photo Engineer]

You need an orange and a blue!

And at the time it was beautiful, but with today's eyes, the look rather poor.

The drying step was to assure that diffusion started the same each time.

PE

 

[falotico]

Mixing dyes

Capstaff in his patents, see US 1315464 issued 1919, calls for "an acid dye (preferably a salt of a sulfonic acid)". I take this to mean the molecule has SO3 groups. These SO3 groups would cause the dye to bind with the gelatin. A wide variety of dyes were available to him at that time and probably there was one of the proper shade of orange and one in the proper shade of green. However, it is certainly possible that the 1920's Kodachrome used a mixture of dyes for either the orange or the green or both.

Dye transfer processes often used a mixture of dyes to form one of the fundamental shades. Technicolor mixed its dyes both to form the cyan and the magenta, IIRC.


Cinecolor, although not DT, famously used a mixture in its two color process for the red tones. The blue tone would be a silver image on one side of the film which was converted to a cyanotype (Prussian blue) by ferric cyanide. But the red would consist of a maroon dye and an orange dye which attached to a mordant created out of the silver image. Red objects would look natural. However when a yellow object was photographed it left a less dense silver deposit in the image and only the orange dye adhered to that. Thus yellow objects appeared orange. The two dyes would indeed express in unequal ratios depending on the exposure, but it had the effect of producing a separate tone for the yellows. Some people said that Cinecolor was a two and a half color process instead of three.


All the DT processes offered considerable post-exposure latitude to the lab. While the results might not meet the high standards of the experts at EK, they are a form of art in their own right, IMHO.

 

[holmburgers]

I must respectfully disagree with my potentate Ron... the Capstaff's look absolutely beautiful to this day! There are a collection of 8x10 glass portraits and still lifes at GEH and they're stunning; legitimately.

2.5 colors; that's an interesting way to look at it. I am surprised that Technicolor would have used a mixture of dyes for the reasons above, but it's certainly possible that two dyes could be found with a close-enough pH/contrast relationship. Kodak DT though, definitely only used 1 dye for each sep.

 

[Photo Engineer]

Chris;

The Capstaff portraits are indeed very nice, but the scene was selected to reduce any faults in the colors. I have seen it used for landscapes and for general non-studio use. In fact, they used to shoot cheap movies on this stuff in the 30s. There, the flesh tones were orange, and the sky was off blue. Many colors were quite distorted.

PE