Would you buy and use a modern Autochrome type film?

[Ian Grant]

As some of the early colour sensitizers are food dyes they are cheap & cheerfull

Others still have medical use in testing labs so again are inexpensive and easy to find. Kodak bought Wratten to get hold of their (and Mees) expertise in this field.

Ian

 

[Photo Engineer]

Running a sheet of film through a printer presents some problems. If you put the screen on the back, then you have to expose through the AH layer. If you put it on the front, then you have to "force" development through this layer. It may or may not work. IDK.

As for sensitizing dyes, chlorophyll and erythrosine are red and green sensitizers respectively. They are inexpensive. You can make your own chlorophyll dye solution easily and erythrosine is dirt cheap from food dye sources. But, are they good dyes? No. They are usable dyes. That is why I use erythrosine as my green sensitizer. It saves money.

PE

 

[holmburgers]

I think the Lumiere bro's used a dye called Orthochrome T for their red sensitivity (check out the "autochrome latex" thread). I too am really interested in knowing about early sensitizers, particularly for red. Ron has showed that erythrosine is a decent green sensitizer, but red has remained elusive at similar prices. I plan to resurvey some of the early efforts (Vogel, Lippmann, Ives, etc.) and see if there's a good candidate somewhere.

Ian, do you have any specific recommendations by chance? A biological stain would be ideal.

Chlorophyll has always interested me, and the method of preparation sounds so simple; soaking blue myrtle or spinach leaves in alcohol. But everyone usually agrees that it's not consistent enough from batch to batch to be usable, and so it's remembered as a curiousity and not investigated.

However, a lot has changed since the late 1800's. Chlorophyll molecules can now be synthesized and are used for a variety of things from food coloring to herbal "remedies". Wiki says, "Extracted liquid chlorophyll was considered to be unstable and always denatured until 1997, when Frank S. & Lisa Sagliano used freeze-drying of liquid chlorophyll at the University of Florida and stabilized it as a powder, preserving it for future use."

More about chrolophyll.

Chlorophyllin is known as "Natural Green 3", food additive code E141 and quote, "Because natural chlorophyll is not as stable as chlorophyllin and is much more expensive, most over-the-counter chlorophyll supplements actually contain chlorophyllin."

So in other words, we now have access to a much more stable and water soluble form of chlorophyll. Interesting...

 

[Photo Engineer]

OTOH, Chlorophyll is a rather poor sensitizing dye in terms of efficiency and in terms of spectral response. A true red sensitizing dye is cyan in color and not green.

PE

 

[newcan1]

I guess I am still in theoretical mode here in deciding whether to jump in and invest in some experiments. My view of the autochromes I have seen on the internet (e.g. the French government site of WW1 autochromes) is that they are awesome regardless of the fact that colors are not accurate. I think I would be more attracted to using, as PE says, a "useable dye" rather than something that guarantees accuracy (after much experimentation by a layman like me) at great cost.

Think of it this way: After all the threads and very interesting experimentation here using computer screens, attempts at registration, screen duplication using reversal film, etc -- what are the odds of getting a halfway decent result by dying starch, coating a glass plate and sealing it, re-coating with an emulsion sensitized with home made chlorophyll and cheap green sensitizer, and taking a picture? I bet it would be a lot easier to get relatively repeatable results, even if at the sacrifice of accuracy, which itself may not be necessary in achieving an awesome result.

I know I am just hypothesizing and I am a long way off of experimenting with emulsion coating (although I am tempted to make some chlorophyll and add it to some Liquid Light). But the steps involved above seem intuitively simpler than many of the other things discussed here, especially those involving registration.

 

[dwross]

newcan1,

I'm currently working out / working on the details of a fairly straightforward, historically faithful autochrome (my personal holy grail when I started making emulsions.) It's looking quite doable. Give serious consideration to learning to make your own emulsions. I think that's pretty much key. Good luck and thank you for consistently thoughtful posts. They make good reading.

d

 

[newcan1]

dwross, thanks for the comment. It's definitely something I am very interested in, although I'm a bit short of resources right now. Maybe later this year, my better half will buy me PE's book and CD, which I assume would be an excellent place for someone like me to start. I used to love chemistry in high school, and now I like the processing side of film developing, so it would be a natural fit.

 

[dwross]

I haven't read PE's book, but I have to assume also that it's an educational publication. I know 'holmburgers' is studying it. Perhaps he can give you some clues without divulging too much of PE's copyrighted info. Anyway, best of luck and fun with your explorations.

 

[holmburgers]

I definitely recommend getting Mr. Mowrey's book when you're able. It's the most up-to-date look we have at emulsions today. I believe most of the information in there is generally public, that is, from patents and publications or from Ron's personal work & experience. The caveat is that Ron is skilled in the arts; he's put it all together.

I really do think that this compliments Denise's approach to emulsion making, or Mark Osterman's approach, and others. Simple and inventive techniques that don't require expensive equipment, guided by a more advanced understanding of what might be going on in the emulsion.

 

[Photo Engineer]

An old truism!

Cooperation leads to graduation!

Thanks Chris.

Pe

 

[hrst]

Emulsion making is a very good example of a process that you can just start doing without too much thought given at that point, and later develop it to higher standards. You can start with very small darkroom, basic kitchenware, food gelatin etc. The odds are, you may get a usable product right away or not, but that's a good starting point anyway. Then it becomes a progressive process of testing, acquiring more information, testing and so on.

I did my first without much planning beforehand.

 

[newcan1]

Well in preparation, I need to eliminate the light leaks in my darkroom and get organized. My darkroom is about 15 x 30ft and there are many places light leaks in -- not enough to stop me doing printing, but faster emulsions could be affected. Also, it seems silver nitrate is about $1 per gram, which would be quite an investment if you need say 50g for a starting batch that might not even turn out properly. This all sounds like something that could be the subject of Christmas presents.

 

[dwross]

Emulsion making is a very good example of a process that you can just start doing without too much thought given at that point, and later develop it to higher standards. You can start with very small darkroom, basic kitchenware, food gelatin etc. The odds are, you may get a usable product right away or not, but that's a good starting point anyway. Then it becomes a progressive process of testing, acquiring more information, testing and so on.

I did my first without much planning beforehand.

Do you mind if I quote you on The Light Farm?!

I've been (trying) to preach that for years, but the conversations here always seem to come back to putting the BIG horse before the cart.

newcan1,
Your impression of what you need and how much you need before you can even get started is a perfect example. You don't need a fancy space, and unsensitized, unwashed emulsions won't be offended by tiny light leaks. You can --and actually should-- make your recipes with 5-6 grams of silver. There are two reasons for this. 1) That's about as big a batch of emulsion has you can reasonably handle at a time, and 2) you'll want to practice, practice, practice.

Think of it like bread making. Would it be ideal to make a batch of dough with 20 pounds of flour? You'd need a commercial kitchen with commercial machinery and ovens. Then, you wouldn't have to make bread for months, but would you even remember how to make bread after all that time? Far better to make small batches as often as possible. Each and every time, you'll learn a trick or two. The learning curve is amazing and an absolute rush. Once you know you love being an emulsion maker, you can commit to ordering more silver nitrate at a time. The bigger the order, the less $/gram. Buy a pound, and it's pretty affordable.

I hope Ron's book has recipes scaled for the home darkroom and the beginner. If not, or even if so, I invite to look at the recipes on The Light Farm. Also, by this fall, I hope to have a new section organized around Jerevan's suggestion/request for a paper recipe that can be made in a temporary darkroom.

Denise

p.s. I'd give anything for a 15 x 30 ft space! I do all my work in a space a Paris chef would recognize.

 

[newcan1]

OK thanks - sorry I didn't mean to divert the discussion here. I just took a look at thelightfarm.com and I think I will be spending quite some time on there. You are right, I had thought I might need a lot more silver nitrate than it looks like I could get started with. I will continue my reading for now. I saw a link Ron had left to an old 1880's book on emulsions and it is truly fascinating.

Again, sorry if I inadvertently moved the discussion away from Autochromes.

 

[dwross]

In my opinion, you've actually moved the discussion in a good direction. Again, just my opinion, but I think the emulsion is key. The color screen is a challenge, without doubt, but it will all come down to the emulsion. I actually don't think many people will choose to make their own autochromes. I don't think the individual parts will be that difficult, but it will be very, very time-consuming. It definitely will not fit easily into the pace of the modern world. If holmburgers is planning on making this a commercial venture (yes! hopefully) he probably shouldn't be worried about d.i.y. competition .

All the very best of luck and fun wherever your creativity takes you. (And, I hope The Light Farm helps.)
d

 

[Photo Engineer]

Well, I think that this thread has moved in a useful direction as well. Because, as Denise has pointed out, this may be the direction needed to prepare a modern Autochrome.

As an added point, due to the cost of Silver Nitrate, I have tried to make the process of making an emulsion as foolproof as possible so that you do not waste money. That is why I use photograde gelatin among other things, rather than food grade, as the food grade variety varies substantially all over the world. These are the little things that that others seem to consider that this approach is not really necessary, but it is there in part, to save you money. It is also there to teach you the highest level of quality. You can do anything you want.

PE

 

[hrst]

Do you mind if I quote you on The Light Farm?!

That would be fun !


newcan1;

The silver nitrate indeed is a cost, but doesn't every hobby cost something? People can use many thousands to just cameras and lenses...

Well, I'm always poor so I made my own silver nitrate. It's very/too easy, but I would not recommend that to anyone because of the very real dangers, if you don't know perfectly what you are doing . (To avoid misunderstandings, I have to add that if you get your silver nitrate, like most emulsion makers do, there is nothing dangerous in emulsion making (just use decent ventilation when using recipes containing ammonia).)

Actually, what drove me to emulsion making was the fact that I simply found most of the ingredients from my Dad's place. Being a goldsmith, he gave me some silver granules, 60% nitric acid and ammonium hydroxide.

I really agree with PE on creating reliable and repeatable processes. Not only because of wasting money, but wasting time too. It can be quite discouraging when the emulsion does not work.

I have found that 100 ml of emulsion is quite a good batch size to practice with. It allows you to test it even with some loss in coating, and get a good starting point for the next emulsion without leftover emulsion. You need about 8 grams of silver nitrate for this. We did 150 ml batches first and there was always quite a bit of leftover. Well, the volume went up in washing, too.

 

[htmlguru4242]

Well, after a couple years of being here, I've returned, only to be bitten by the Autochrome bug again ... curses on all of you! ... just kidding on that last part.

Anyways, I'd love to join all of you in your quest to resurrect these processes. As some of you may recall, I did some experiments a few years back, so I'd love to lend a hand in getting all of this going.

With photo products disappearing from the market left and right, it would be outstanding to see something like this re-appear!

 

[holmburgers]

It's great to see you back on here guru!

It is definitely a voracious bug, and I think one that will eventually lead someone to make a real screen-plate product. At present I think that getting a good panchromatic emulsion is step numero uno, and then making a screen.

 

[htmlguru4242]

And it's good to be back!

The emulsion may be priority number one, but there's no reason that it has to be designed before or after the screen-place. We have enough people working on / interested in this that both tasks could be worked on in parallel with no problem!

Reproducing an -original style- screen may very well prove to be more difficult than the emulsion. Even though it's relatively difficult to make the emulsion, we have extensive documentation and the likes of Photo Engineer to help with that. The info on the original plates (unless i've missed something) is scant and conflicting, at best.

Does anybody like the idea of co-ordinating some distributed efforts?

 

[holmburgers]

Well to be honest, I've got some "plans" in the works that I hope to reveal in full soon. This might sound a little cryptic, but I'll explain in (hopefully) a few days. In short though, I'll be able to spend a lot more time focusing on photography in the near future, and working on both a panchromatic emulsion and a screen are gonna be high on my personal to-do list.

For a screen, I'm more or less set on an idea that would create something resembling a Dufaycolor reseau, utilizing the original technique described by Louis Ducos du Hauron. Basically it would be a dichromate (or similar) procedure with mutliple etching steps.

If I thought that coating a screen with starch grains and subsequently filling in the interspaces with carbon black could be easily done, or rather, if I understood how the heck that was done!, I might be interested in thinking along those lines. Dying the starches and varnishing them onto a plate would be trivial, but the coating/calendaring procedure is beyond me. There are a number of other ways that one could theoretically make a random screen reseau, but none that have really struck me as practicable. I'd love to know if anyone else has some ideas on that.

In other news, I know that Denise over at the Light Farm has started messing around with panchromaticity seriously and she too is interested in reproducing the Autochrome. However, she seems to be taking something of a hiatus (or she's holed up in the lab!).

Regarding the dyes that one could use in coloring starch grains or similar, we needn't look further than the acid dyes utilized in Kodak's dye-transfer system. Just as is done with some Wratten filters, combinations of C+M, C+Y and M+Y can get us the appropriate red, green and blue filter colors, and they'd have rather good permanency. Jim Browning has published his set of dyes, and there is a large list in my dye-imbibition thread. All of these are relatively easily obtainable "articles of commerce".

On the other end of things, lately I've been identifying a vast number of spectral sensitizing dyes ((there was a url link here which no longer exists), see the latest handful of posts) that could be used in emulsions; particularly old and cheap ones.

 

[htmlguru4242]

A dichromate / etching process sounds like a great idea ... I think I can even picture in my head how that might work.

As far as creating a -random- reseau, doing it [gasp] digitally would be the best way, especially if the end goal were to be a commercial project. It would be trivial to have a computer generate a random dot pattern, normalize it to obtain the correct color balance, and print the resulting image. There's no reason that an inkjet printer can't be loaded with RGBK instead of CMYK ... This could be done on large sheets, which could then be cut down to the correct size.

 

[holmburgers]

I encourage you to go the inkjet route for sure, but my main concerns are permanency and resolution. They're probably not insurmountable by any means, but those are my initial thoughts. I recall that you posted a RGB reseau file in the past and I might even have it on my computer somehwere. I have to admit thought that I'm not gonna fiddle with inkjets; but like you said, this could be a collaborative effort.

 

[htmlguru4242]

I looked at the method you're talking about (in the history of color photo book) - brilliant! I can't wait to see how that comes out for you!!!

 

[holmburgers]

Just for fun I thought I'd post this Kodak patent for a Film with Color Filter Array, U.S.P. 6,387,577.

It's interesting that Kodak has patents from so recently that deal with making, basically, screen-plate reseaus. Of course, there is application for digital sensors (Bayer arrays), but this one in particular would be suited to film.

It's a brilliant idea and would allow the screen to be in front of the emulsion, yet allow processing like normal. As opposed to exposing through the base like a typical screen-plate.