Capstaff's two-colour Kodachrome process.

[johnielvis]

whups---I just read up on the edwal "toners"...they tone the highlights...so that's not gonna work. need to use toners that tone the silver portions---I remember uranium toner is red---I figure get a standard toner "process" and then match the exposure filters (use cc filters if necessary even) is the easiest since there's an easy variety of filters for exposure

 

[holmburgers]

Hey Elvis,

Yep, like you discovered, those toners won't do the trick. You need to actually replace the silver with dye somehow, so that the dye is in proportion to the silver. Highlights should be clear (just as they would be with silver) and shadows full of dye.

You're also right about needing 2 separate light sources if you're going to use filters to create the color; this is heading into additive country. You could do this too, and just use silver negatives with appropriate filters to view each through. The trick here is that you'll need to combine them for viewing somehow. This is analogous to the Kromskop.

You could try dye mordanting with basic dyes (something like this, pg. 755), or making a gelatin relief image and using acid dyes, like dye-imbibition.

Basic dyes have no affinity for gelatin, hence they need a mordant which can be made via the silver, whereas acid dyes generally are attracted to gelatin and so all you need is a gelatin relief image (think carbon method, or you could try a dichromate bleach). Realistically I think those are the two best paths.

 

[kb3lms]

You need to actually replace the silver with dye somehow, so that the dye is in proportion to the silver. Highlights should be clear (just as they would be with silver) and shadows full of dye.

To do this, aren't you talking about something like kodachrome (as in modern) couplers?

 

[holmburgers]

No, there are easier ways to do it.

 

[Steve Smith]

Hollywood also had its early flirtation with two-color photography

I found this a while ago: http://www.youtube.com/watch?v=NObu5VXfTVI&feature=endscreen&NR=1

I think it is a two colour movie film process. Gasparcolor.


Steve.

 

[Photo Engineer]

Gasparcolor was 3 color and used dye bleach.

PE

 

[holmburgers]

Steve, thanks for posting that, it looks really great! PE's right though; it's 3-color dye-bleach system, a precursor to Cibachrome, developed by Hungarian Bela Gaspar. A very interesting process, but only useful for printing color from separations, not capturing color directly from the scene (IIRC). It was widely used for animation also.

 

[Neanderman]

Coming in here a bit late, I'm pretty much thinking out loud, and it's probably a stupid question, but would it be possible to use C-41 or E-6 type couplers, in solution with one of the CD's, as a second developer on standard, reverse exposed B/W film? Or do those families of couplers have to be adsorbed to the silver halide crystals to work? (So what I'm envisioning is sort of a split K-xx process, where the couplers and developer are in the same solution, using two -- or three -- separately exposed standard b/w films, which would then be sandwiched.)

I think PE has said you could do this with the Kodachrome couplers, but since those aren't readily available, that's not a viable solution.

Ed

 

[Ian Grant]

Yes, I've done this for well over over 30 years for colouring B&W prints, I use raw couplers but Tetenal made a dye coupler kit, not sure if it's still available. Jave alsom used colour couplers with B&W films.

Ian

 

[johnielvis]

Hey Elvis,

Yep, like you discovered, those toners won't do the trick. You need to actually replace the silver with dye somehow, so that the dye is in proportion to the silver. Highlights should be clear (just as they would be with silver) and shadows full of dye.

You're also right about needing 2 separate light sources if you're going to use filters to create the color; this is heading into additive country. You could do this too, and just use silver negatives with appropriate filters to view each through. The trick here is that you'll need to combine them for viewing somehow. This is analogous to the Kromskop.

You could try dye mordanting with basic dyes (something like this, pg. 755), or making a gelatin relief image and using acid dyes, like dye-imbibition.

Basic dyes have no affinity for gelatin, hence they need a mordant which can be made via the silver, whereas acid dyes generally are attracted to gelatin and so all you need is a gelatin relief image (think carbon method, or you could try a dichromate bleach). Realistically I think those are the two best paths.

yes--I'm reading up and I think I can start off using something like the formulary toners for paper--there's an iron toner that'll give me green and a copper toner that'll give me red...for 2 color process, all I have to do is then just find the right filtration and relative exposure and hopefully I get something looking like that early kodachrome---

for more flexibility I guess the mordant and dye is the way to go, but then it's time to start hunting for dyes and experimenting...

I'm thinking of a 2 color--direct reversal (2 positives--one a reversed image)---the silver is toned using the copper for one and iron for the other or suitable mordant---apparently the mordant method would simplify and speed things up--I can apply the morant after the dichromate bleach step and skip the whole regular reversal development process....just develop-bleach-mordant-dye-develop-DONE, right?

 

[johnielvis]

Yes, I've done this for well over over 30 years for colouring B&W prints, I use raw couplers but Tetenal made a dye coupler kit, not sure if it's still available. Jave alsom used colour couplers with B&W films.

Ian

are these "couplers" the same thing as "mordant" then? tetenal HAD this already????now THAT sounds promising...maybe...or depressing, depending on how you look at it...

 

[Photo Engineer]

Couplers are not mordants.

Mordants are chemicals that hold soluble dyes in place in some material such as cloth or film. Couplers are materials that form dyes through a two step or three step process involving a reducing agent and an oxidizing agent. In film, this is the Silver Halide and the developing agent.

PE

 

[holmburgers]

It'll be interesting to see if the toners can do the trick; maybe so! There were a couple dye-toning tri-color processes too, so it just goes to show you that toners can create a wide range of usable colors.

I've not really looked at the mordant processes seriously yet (in terms of the procedure) so I can't be certain when in a reversal process you'd wanna stick it. I think though, that you'd need to develop up the positive silver before you could turn it into the potassium iodide mordant, viz. the Ives process.

Finding dyes for this might not be hard. There are a thousand basic dyes on eBay that are used in biological staining and other things. Malachite green is one from the top of my noggin.

Alternatively, if you look at Capstaff's patents on this process, his method for sticking the dye in the gelatin is by a dichromate bleach not unlike one found in reversal processing or carbro. Heck, the first patent (IIRC) goes from a negative to a dyed positive via this bleach in one step. He later patented a method to do this from a positive to a positive (better for printing to movies).

Although chrome salts can be mordants, in this instance it's not strictly lending any mordant action, but rather it's the hardening differential set-up in gelatin that "involves" the dye. This requires acid dyes, loosely speaking, that might easily be found in the textile industry.

Sorry if I'm repeating myself a bit; some tricky concepts here, and I don't think it hurts to reiterate and say things differently. It certainly helps me make sense of it all too...

In the end, I hope you give it a go with any method you like!

 

[holmburgers]

This is a really amusing little multimedia thing from PBS. It actually takes you through making a Capstaff Kodachrome... well kind of.

Anyways, pretty cool, check it out.

http://www.pbs.org/wgbh/amex/eastman/sfeature/color_kodachrome.html

 

[johnielvis]

awwww...I thought they'd show the 2 color camera and everything...not even close--just a tutorial....

I've seen something similar to this before--very similar but with the full 3 colors--same type of demo-"you build it".

 

[holmburgers]

Yeah, it's kind of juvenile for sure, but I was amazed that this fairly esoteric process had it's own multimedia thingy.

You raise a good point though, we haven't really discussed the "taking" mechanism for this process at all. We've just taken for granted that we have 2 separations.

And to be honest, I don't know how they secured these seps! I believe that at some point, particularly with movie film, that they used a "duplitized" film stock, that is, 2 emulsions coated on either side of the film & appropriately sensitized. Then for processing, either side was floated on the appropriate dye bath.

But as for the big glass plates... anyone know?

 

[Photo Engineer]

I have never seen anyone make a Capstaff film, but I just finished watching some motion picture footage of Capstaff himself playing himself and a movie starlet! He really dressed the part! And, he and his friends had a lot of fun.

PE

 

[holmburgers]

That's hilarious.. did you see a projection of the original film, or a reproduction of some sort? Only in Rochester!

I guess Capstaff's grandson is a painter in the Rochester area; he's got a blog somewhere and he talks a bit about both of his grandfathers. The other was a painter; so, also into color but from a different perspective.

What greater gift than to see in color!

 

[Photo Engineer]

This was a film with Capstaff, Sheppard, Trivelli, Ross, and Mees among others. It was very well done and very funny. Narration was by Dr."Knobby" Clark.

PE

 

[holmburgers]

Amazing.. that sounds like a treasure.

 

[johnielvis]

wellmethod is the starter--I see that there are NOW suddenly a lot of very inexpensive LARGE beamsplitter mirrors available--so this is THE time to build a 2-image (one reversed) camera. These are for 3d viewers that people are building--3dmirror dot com or something like that.

as far as filters...man--I guess the easiest would be to use the larger holographic plates---green sensitive and the other red sensitive--these I don't think are very fast though...but they are dimensionally stable, won't sag like film--so registration is not a problem--AND they are already "filtered" you need not get large filters to go over the film/plates.

so this is doable if you have the woodworking tools...oh, THEN you gotta tone these plates....and if you want to do portraits, I think maybe these plates may be too slow--maybe not--I was going to do some speed testing with a holograph plate kit I bought a couple of weeks ago, but I used all the plates making holograms (or trying to make holograms)....I got some, but disappointing....1/2 didn't even turn out

but this ain't about holograms...

 

[holmburgers]

Hmmm, holographic plates aren't cheap and they're as slow as molasses, if not slower. This seems a bit like going to the moon by way of Venus! If 4x5" or 8x10" film sags too much for registration, maybe you could sandwich them between two pieces of glass and shoot them in a spring-plate pressure plate.

For me, figuring out the dye process is paramount and everything else is secondary, but I can't fault you for being imaginitive.

 

[johnielvis]

right...toning is the first thing....the only problem with toning is that different films tone differently....

I do have it on my to do list to get them formulary toners and see what they do with film...I wanted to make a large color portrait camera taking 11x14 film--yes-I guess a larger sheet of glass (filter dyed) with film pressed against it will work fine....

filtered film is slow too---the hologram film is "slow" but I don't know how slow--didn't get a chance to try it out with regular exposures because the slavich plates I got were too thick for my hasselblad film/plate holders...maybe the ilford ones are thinner...gotta see--I don't think it'd be THAT slow...only one way to find out and I missed my chance with the materials I had...

alternatively--hologram FILM with no anti-halation backing can be sandwiched together....make a bipack with that...so maybe I'll try that out...I believe the film is clear and lets light pass just like the plates, so this should work in a regular camera straight off....2 pieces of film in a regular filmholder would be nice and tight perhaps and not sag.....this is definitely doable if the toners work...I noticed that copper sulfate bleach will leave a blue/greenish tinge and dichromate bleach will leave a reddish tinge--so maybe no TONING per se is needed...just bleach and don't clear the bleach from the emulsion before re-developing and let the dichromate do it's job....or just dont redevelop..right...bleach away and leave the stained silve salts...but they will fade with print through in time...but hey...quick and dirty, right?

 

[holmburgers]

An in-camera exposure on a holographic plate is going to be something like 2 minutes at f/8 in bright sunlight, or at least that's what it takes for a Lippmann developer ((there was a url link here which no longer exists)).

A much simpler approach would be to take sequential exposures of a still-life, and/or, make separations of the red & green from regular color film.

You should look into true color toning, where the silver becomes C/M/Y. There was a process called Defender Chromatone that used this method. Unfortunately, the toning solutions where proprietary, but I think there are some formulas in Friedman's History.

 

[johnielvis]

that exposure was to record lippmann interferance-not a standard silver image-it was badly solarized indicating gross overexposure--gross overexposure isn't going to be cured with one stop, but many

I'm gonna try--I think the speeds may be reasonable for portraiture--I made holograms with the red sensitive ones with a teeny tiny laser of hardly any power (laser pointer) and that took like 20 seconds....what I'm concerned about is lack of dmax BUT then I can intensify the both of them or the toner can be the intensifier---sort of "grow" the color on them maybe...first gotta get some film and try it out for usable speed