I'm getting my "Autochrome" experiments going again ...

[Kino]

And I'll share the info. if the people I get it from don't have a problem with it. I'll of course ask, but in the research of an old process like this one, it would be useless to keep the information to yourself.

I brought it here because of hte greay group discussion that [usually] occurs here. I don't have the skills, time or money to completely research and tinker with everything my myself, which is why this is here.

I didn't intend to make as issue about ANYTHING.

I agree with you totally.

Frank

 

[htmlguru4242]

Oops, double post, read below ...

 

[htmlguru4242]

I've been looking around online and there seem to be some good suggestions for coating methods, which are very similar to what I used, so the actual starch coating I think is going ot be ok.

However, I have two MAJOR questions, which i need to work on.

1.) What kind of dyes are best? The food dyes do not really work, especially on potato starch.

2.) How is the lampblack coated on? Of the whole process, the details on this are the most shaky. Everything says that a "special machine" was used for coating it.

On the same note, is there an easy way to produce large quantities of lampblack?

 

[Lachlan Young]

Do the Lucky films lack an anti-halo layer?

Their anti-halo layer is widely regarded as largely ineffective or almost non-existant if that is what you are after.

Hope this helps,

Lachlan

 

[Photo Engineer]

Lampblack can be purchased commercially as a powder or as a pre-made dispersion in a material suitable for coating. This is used in carbon printing.

Dyes are also available for carbon printing. If they are properly placed on starch grains, they would be appropriate dyes for the autochrome filter mask.

PE

 

[Photo Engineer]

Well, PE that is just fine and dandy; I think you have made your position perfectly clear to everyone.

Got it. OK?

If no one wants to share, I can go develop it myself and post it all I like, right?

I would never post anyone's confidential information if they preferred me not to, but there is certainly more than one way to skin a cat; even in photography.

While I respect others rights of others to develop their processes and tweak them to their standards, they don't own the Autochrome process anymore than I do and, should I run across a similar method or develop my own, I will post it for all to see and that is my prerogative.

I don't see how taking this discussion out of APUG (effectively killing it) and putting it into the hands of photographers who, for whatever reason, don't want their methods published, advances the art of photography for the members of APUG.

I would rather have an imperfect process and learn about the underpinnings of photography than have a closed-loop system of near-perfect images and not learn a thing beyond the characteristics of that particular flavor of the process.

If you make a living or have a substantial investment in a process, as you and others obviously do, then I congratulate you and respect your right to keep this information proprietary and would, if I can ever afford it, like to take your class on emulsion making, but it won't bind me to not exploring or sharing emulsion making outside of your specific techniques and methods.

Htmlguru, if you'd like to and are in a position to share ideas, knowledge and specific bits of technique, I am interested and assume others are on this forum.

It kind of IS the whole idea behind APUG, right?

Frank W.

Kino;

Several of these people are rather well known in their own right and don't post at all or seldom use the internet. One has been harassed continually when he did post, and so he quit! One is a very very old man with a poor command of English who does not like to use the internet.

I don't give out these e-mail addresses for this reason, and I don't give out information from others unless they give permission.

I agree that information should be shared as much as possible, but read my post on using real names on APUG. I myself have been getting phone calls up to 3AM and it is quite distressing to me and my wife. These phone calls are quite nasty and threatening and we are working with the authorities to fix the problem. As a result thought, I really truly respect the privacy of others.

Just FYI, as I posted elsewhere, one of the individuals in question here, who is an expert on Autochrome, posted some emulsion work on a site a few years back and got an 8 page anonymous threatening letter. His wife made him quit posting!

Please think on that before you become overly critical of my method of operation here. And, I am sorry if it offends you. While it does that, it protects the privacy and peace of mind of others who are personal friends of mine.

As it is, I have to approach these friends with an anonymous person (htmlguru) and see if they will consent to talk to him via e-mail or phone. After their prior experiences, I really don't know how it will work out.

PE

 

[Kino]

Kino;

Several of these people are rather well known in their own right and don't post at all or seldom use the internet. One has been harassed continually when he did post, and so he quit! One is a very very old man with a poor command of English who does not like to use the internet.

I don't give out these e-mail addresses for this reason, and I don't give out information from others unless they give permission.

I agree that information should be shared as much as possible, but read my post on using real names on APUG. I myself have been getting phone calls up to 3AM and it is quite distressing to me and my wife. These phone calls are quite nasty and threatening and we are working with the authorities to fix the problem. As a result thought, I really truly respect the privacy of others.

Just FYI, as I posted elsewhere, one of the individuals in question here, who is an expert on Autochrome, posted some emulsion work on a site a few years back and got an 8 page anonymous threatening letter. His wife made him quit posting!

Please think on that before you become overly critical of my method of operation here. And, I am sorry if it offends you. While it does that, it protects the privacy and peace of mind of others who are personal friends of mine.

As it is, I have to approach these friends with an anonymous person (htmlguru) and see if they will consent to talk to him via e-mail or phone. After their prior experiences, I really don't know how it will work out.

PE

PE,

I am sorry you are having problems with persons who, from all accounts, appear to be crazy; it shouldn't happen to anyone.

I am not going to re-tread what I said in the previous post; it remains true and I won't argue the points you keep bringing up, as I have agreed with everything you are saying.

Anyhow, this thread is about the Autochrome Process and what APUG members can bring to the table; any further discussion outside of these lines should be carried out via private messages.

thank you
Frank W.

 

[Kino]

1.) What kind of dyes are best? The food dyes do not really work, especially on potato starch.

I wonder if the Kodak Dyes used in Dye Transfer printing might work here?

2.) How is the lampblack coated on? Of the whole process, the details on this are the most shaky. Everything says that a "special machine" was used for coating it.

The descriptions I have read of the process (right or wrong), state that it is added last over the RGB starch particle mixture to fill in the spaces before rolling the plate to flatten the grains.

 

[Kino]

Their anti-halo layer is widely regarded as largely ineffective or almost non-existant if that is what you are after.
Hope this helps,
Lachlan

Lucky probably uses a clear AHU (anti halation underlayer) like some of the modern Orwo and Kodak stocks use. That would certainly seem to be preferable to an opaque layer that has to be removed.

 

[Photo Engineer]

There is a complete set of C/M/Y dyes listed on the Dye Transfer web page of Jim Browning. If you wish B/G/R dyes, this is not too difficult, but is less common.

A very good blue for this is Chicago Blue. That is about the only one I remember that is commercially available and fits the "blue" category.

The dye transfer dyes were designed to be water soluable and to be held fast by a mordant. This may not work for the Autochrome process. Some of my sources indicate that you may want oil soluable dyes to go into the starch grains.

And, BTW, my notes are out to those I know who work in or know about Autochrome. When I get answers, I will let you know. That information that they want published will appear here immediately, as fast as I can post it. I assure you.

PE

 

[htmlguru4242]

Well, a clear AH layer would be nice, so long as it doesn't prevent light transmission through the base of the film. I seem to recall seeing a purple-ish layer on the back of the Lucky film, though that wasa year or two ago, so it very well could have changed since then.

Thanks for the dye suggestions, PE. Do you have any idea as to pricing / availability of these?

 

[Photo Engineer]

I have not looked into the price of some of these dyes much lately, but the ones I have gotten have run in the range of $25 / gram.

There is an Oxonol dye I have found that might be a good red. That was cheap. Tartrazine, also inexpensive, is a good yellow as is Metanil Yellow. I have used all of these.

A good magenta might be Erythrosin.

I'll keep looking, but I don't have a good green dye to suggest, nor really many substutes for the others I listed.

These are all high molecular weight dyes with solubilizing groups on them so they dissolve well in water or in alcohol. You will have to mordant them to the starch.

PE

 

[htmlguru4242]

Ok, those are good suggestions. What would said dyes be mordanted with?

 

[Photo Engineer]

A quick test is to try to directly dye the starch with the dyes and see if they wash out. If that does not happen, then the dyes are adhering to the grains. You need go no further.

If the dyes wash out, then try another run, dying the grains, decant the water with excess dye, and then add some aluminum sulfate or calcium chloride solution to the solution of dye and starch. Then the dyes will both precipitate in solution and in the grains of starch. At this point, it will be possible to separate the dyes in solution from those in the starch. Those in the starch will settle to the bottom along with the starch and you can then decant the excess fine particles of precipitated dye.

Now you can wash the excess salts off the starch grains leaving dyed starch behind.

Sometimes this is done in the gelatin matrix you are going to use to coat on film.

Then you measure covering power of the R/G/B or C/M/Y batches and mix them in proportion to their density. So, if 1 g of R = 3.0 density and 1 g of B = .9 density and 1 g of G = 1.3 density, you can work out ratios to give you a neutral from these 3 figures. If you adhere to this and mix in the carbon in gelatin, you get a neutral that has filtering properties adjusted for the film. A few test shots will determine how to rebalance based on spectral sensitivity of the selected film.

I have a spectrosensitometer, if you wish me to make wedge spectrograms of either your chosen film or of your color material when the time comes.

I have published some of these on APUG, so you can get a look at what they are like. Also, there is a chapter in Mees or Mees and James on the subject with example data.

PE

 

[Kino]

I can post part of a chapter of a book that describes Color Screen Plate Processes in general and specifically Lumiere Filmcolor, Lumiere Autochrome, Agfa Ultracolor and Dufay Color (ignore the last one).

The question arises, do you want the historically accurate color gamut of the original Autochrome or do you want to make a more modern version of the process?

If I am reading this chapter right, the original Autochrome plate used orange, green and blue-violet starch grains in a parts- perportion of 4 green, 3 orange, and 2 blue-violet ; that is what gave it the characteristic "salmon" color. Later "Filmcolor" plates by Lumiere used the more traditional RGB mixture.

Would it be better to upload it to the formulas section or just dump it here?

Frank

 

[htmlguru4242]

I'd post it here, I'm not sure if its specific enough for "formulas". I'm assuming that those colors were used de to the sensitivity of the original emulsion (orange was problably used because its red sensitivity was not too good).

I'm not familiar wth Filmcolor; what was that process? And, as I remember reading, ultracolor (AGFA) was the predecessor to AGFAcolor and was a screen-plate process with a plate of resin beads.

Heh, Dufaycolor. The examples I've seen aren't THAT bad, though they sure are DARK.

I've only seen the RGB Autochrome plates, I've never actually seen one of the orignal Orange-green-violet ones, though I've seen prints from them.

 

[Kino]

I'd post it here, I'm not sure if its specific enough for "formulas". I'm assuming that those colors were used de to the sensitivity of the original emulsion (orange was problably used because its red sensitivity was not too good).

I'm not familiar wth Filmcolor; what was that process? And, as I remember reading, ultracolor (AGFA) was the predecessor to AGFAcolor and was a screen-plate process with a plate of resin beads.

Heh, Dufaycolor. The examples I've seen aren't THAT bad, though they sure are DARK.

I've only seen the RGB Autochrome plates, I've never actually seen one of the orignal Orange-green-violet ones, though I've seen prints from them.

That color starch mixture might prove useful if you/we have to wind up using an emulsion that is lacking in green and red sensitivity.

Personally, I am drawn to the original version, but it might be neat to work concurrently on a historically accurate version and a modern version as well.

The book has a number of formulas related to Screen color processes; some useful, some not so useful. The plate varnish formula for covering the color screen before coating with emulsion might prove useful.

I'm not real clear on the distinction between Filmcolor and Autochrome, as the two terms seemed to be used interchangeably sometimes and not other times...

No, Dufaycolor can look very interesting, but once you start trying to copy them photochemically or scan and work with them in that other system that involves computers, the moire patterns and the spectral cut-off of the dyes are a nightmare to deal with. You have to use a very carefully modified dual light source lamphouse (tungsten and sodium vapor) with a chemical band-pass filter that blocks certain parts of the spectrum or you wind up with muddy crap.. ugh.

OK, give me a few days to get it OCRed, as this old book's serif typeface promises to be a nightmare; I often just break down and manually type it in and scan the plates as it takes less time.

 

[htmlguru4242]

The plate varnish would be great. Does it use things that would be available to the modern experimenter?

I definetely agree with the idea of using the historically accurate colors. However, it MAY prove easier to use RGB dyes, if they are more available. We shall see.

Does hte article list any coating or preparation methods?

 

[ZorkiKat]

I'm not real clear on the distinction between Filmcolor and Autochrome, as the two terms seemed to be used interchangeably sometimes and not other times...

.

Jack Coote wrote in his book "The Illustrated History of Colour Photography" that "Filmcolor" was the film-based version of Autochrome which were coated on glass plates. It was only 1932 that Lumiere were able to overcome problems associated with pressing the starch screen and emulsion coating on a plastic base. Lumiere also had "Lumicolor", the improved version of Filmcolor. Their last additive screen colour film was "Alticolor" of 1952...interesting that such even came out at a time when everyone else were making multilayer subtractive emulsions.

Why was the orange filter necessary for Autochromy?

BTW, Coote's book devotes many pages to Autochrome. The process of manufacture is described in detail, though not the extent that a DIY Autochromist might want. Also lots on Dufaycolor, Finlaycolor, Agfacolor (original) and hosts of other screenplate additive processes.

Jay

 

[htmlguru4242]

If you're speaking of the orange grains used instead of red, I believe it was due to the lack of good red senitivity in the emulsion.

I'm thinking that you're PROBABLY talking about the orange / yellow filter used over the lens while taking hte picture. This was because the emulsion was much more sensitive to blue light than to all of the other colors. In order to prevent overexposure of blue in the final transparency, a yellow or orange filter was used to cut down on the amount of blue light entering the camera without significantly affecting hte other wavelengths.

 

[ZorkiKat]

I'm thinking that you're PROBABLY talking about the orange / yellow filter used over the lens while taking hte picture. This was because the emulsion was much more sensitive to blue light than to all of the other colors. In order to prevent overexposure of blue in the final transparency, a yellow or orange filter was used to cut down on the amount of blue light entering the camera without significantly affecting hte other wavelengths.

It's the use of an orange filter over the lens during exposure. I'm not sure what sort of orange this was, perhaps its like the tungsten-daylight conversion filter?

One more point in Cootes book about the improvement on the "Lumicolor" was the incorporation of the orange filter in the film, to eliminate the necessity of
using one over the camera lens.

Jay

 

[htmlguru4242]

Everything that i've read says that it was a yellow filter, and probably a light one. It needs to cut the blue light somewhat, not completely remove it. I don't believe that this would be necessary with today's films or emulsions that would be used, as their sensitivity is equal enough across the spectrum. Perhaps a VERY light yellow could be useful, though I REALLY don't think so. Only experimentation would tell.

Now, the filter mask being built into FIlmcolor is interesting; how does one prevent the mask from showing through on the finished transparency? unless the color were to bleach out ...

 

[htmlguru4242]

Ok, I've been reading a lot of things online very carefully, and it seems that I have been going about coating hte mask in the wrong way. It seems like in the original process, the adhesive (a mixture of pine pitch and beeswax [shouldn't be too hard to reproduce]) was mixed up and coated in a thin layer. It was then left to set up until it was just tacky THEN the starch was dusted on, rolled flat, left to sit and coated with lamblack.

I've been using modern adhesives that only accept the starch when wet; they dry rahter than becoming tacky. I don't think that the adhesive used ever actually dried, it was just a sticky coating. Hence the varnish used to protect it.

And Kino, is that varnish formula that you have the one used over the starch layer or the one used over the emulsion after development? Because I know that the finished plate was varnished for protection.

I want to know how the Lumieres managed to coat all of this stuff onto a plastic film base later on ...

 

[Kino]

Yes it went over the starch and the emulsion coated directly over that. You make the varish by dissolving three parts of "gum dammar in 1000 parts benzol", according to the book.

Now the "gum dammar" looks fairly benign, but the "benzol" looks uncomfortably close to benzine, so a different solvent might have to be sourced out.

At work now (naughty, naughty) and will try to respond tonight with better answers...

Frank

 

[htmlguru4242]

I'm at work as well, though i have periodid lulls of stuff that i do, during which i post.