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Photo Engineer
04-04-2008, 11:59 AM
Well, after some lengthy darkroom work, I can lay out some basic parameters for those interested in getting into the field gently or go all the way.

First, the basic emulsion making can be done with a beaker, hotplate and syringe and the coating can be done with a paintbrush or a coating blade. Costs for this entry level are about $1000 or so. This is the low end and you can make the Azo paper, the Brovira-Kodabromide hybrid, or the ISO 40 ortho emulsion.

Adding on to this, you may want to make and coat pancrhomatic emulsions and this will involve another $500 - $1000 for sensitizing dyes and IR goggles and safelights.

Going a step further though involves pumped silver and salt, UF wash and other tricks to get into the ISO 100+ speeds or more esoteric paper emulsions involving cubic or octahedral chloro-bromide or chloro-iodide emulsions. This is what I will address here.

A basic peristaltic pum such as a Masterflex pump will run about $1200. The heads (and you may need 2 or 4 depending on flow rate range) will run about $200 - $300 each. If you go for the diaphragm head it will run about $500.

This allows you to make monodisperse, high contrast, high speed emulsions or any of the modern types.

Since they need to be washed, you need a UF unit. This I don't have working yet, but it is clear to me that you need a high pressure pump and a good cleaning system. You can go with either a plate and frame UF unit or a spiral wound UF unit. The cost of these runs between $200 and $1000 for a lab scale unit without pump. The Masterflex pump above may not be able to handle this.

You will need tygon tubing for the peristaltic pump and pvc tubing for the diaphragm pump and for the UF unit due to the temperatures and pressures involved.

So, a high end lab for high speed emulsions will run an addition $2000 - $3000 to set up.

To do the hand coatings, only the blade will allow you to coat paper, film and glass at widths from 4" to 16" with near production quality. I know that some will argue this, but I ask you not to argue until you have actually tried to get 90%+ yield on a 16" wide sheet of film or paper without a blade.

Now, the other alternative is Jim Browning's coater. Having used that, and having produced a perfect 30x40 film sheet on the first try, I know that works as well but at about 10x the price. You can also coat paper on it, but it took Jim and me about 2 days to figure out the settings on the machine to do that.

So, there is a low cost and a high cost method of getting good cotaing quality.

This post puts everything in one place for planning that portion of the book and DVD. Comments are needed.

Thanks.

PE

CRhymer
04-04-2008, 12:23 PM
Hello Ron,

While chemicals like silver nitrate and additives can be pricey and may also fluctuate in price, I was surprised to find that (good quality) paper is a substantial cost. For the home coater, the paper itself can be a substantial portion of what good quality off-the-shelf enlarging or contact paper would cost. I know that three of the goals here are developing skills and capacity for the day when commercial products disappear (already an issue), getting control of the product to do exactly what one wants for artistic reasons, and the satisfaction of doing it oneself. The reason I mention the paper, is that one needs a good coating method (for me a blade) or the cost of duds can soak up a lot of expensive paper quickly. While one can practice on cheap paper, the type of paper (baryta, etc.) makes quite a difference to the "feel" of the coating process. Also, I would say that one could get into this for somewhat less by buying surplus equipment, but in fact I think your estimates are fairly conservative. I have invested a lot more, but some of that represents the stockpiling of materials that I may not use in any volume for some years and the fact that shipping is rather expensive for me.

Since people often acquire these things a bit at a time or have some things on hand, the start up costs are not always obvious.

Furthermore, Melinex isn't cheap either, but at least it is available, for the time being.

Cheers,
Clarence

Photo Engineer
04-04-2008, 12:27 PM
Clarence;

I agree. That is why I use rather inexpensive Strathmore papers which give quite good quality with a warm ivory tone and a matte surface. It is also why I coat a lot on glass. This saves a lot of money.

I believe that some of the circulating samples of my work by Alex Hawley may be on Strathmore and Baryta both.

PE

chrisf
04-04-2008, 12:49 PM
Hi Ron,

I was under the impression that wider blades were problematic in milling. If I can get a 16" blade to coat 11 x 14 that would be of interest to me. The cost of the blade wasn't mentioned above.

chris

dwross
04-04-2008, 01:31 PM
Ron:

As much as it pains me to argue with you in public, I can't let your assertions about the cost of getting started go unchallenged. Please go here for an alternative path. http://www.thelightfarm.com/Map/KitchenLab/MapTopic.htm

Also, although I am very fond of your 4 inch blade, there are affordable and very satisfactory alternatives to a blade for coating. Please see here:http://www.thelightfarm.com/Map/PaperAndCoating/MapTopic.htm

The glass emulsion wells will be available within 10 days for $100.

I would sincerely request of anyone who is interested in getting started making emulsions to just give it a go. Start small, start simple. It's very affordable compared to good commercial b&w paper and downright "free" compared to Epson ink cartridges and fine art inkjet paper. I understand the siren call of mechanization. That can come in steps, large or small. But, first make an emulsion. Cost it on some paper. Expose it under a light bulb with a stopwatch. You'll be hooked. Share your discoveries here and/or on The Light Farm. The more hands, hearts, and brains approaching this topic, the faster and better it will grow. A few years from now, it will be as accepted to make your own silver gelatin paper as it is to coat Pt/Pd. Those of you who remember when The Keepers of Light was first published, will know implicitly that I speak truth.

From the Emulsion Makers pulpit,
Denise

Photo Engineer
04-04-2008, 04:05 PM
Hi Ron,

I was under the impression that wider blades were problematic in milling. If I can get a 16" blade to coat 11 x 14 that would be of interest to me. The cost of the blade wasn't mentioned above.

chris

Chris;

Yes it is a problem and the single 16" blade needs resurfaced.

PE

Photo Engineer
04-04-2008, 04:12 PM
Denise;

Of course there are many ways to coat and many things to coat on. I would be a fool to say otherwise. But if you stack up all of the costs you have put in to making emulsions - minus any of my blades, you would be in the $500 - $1000 range I suspect. But there is a broad price range. Just as Clarence pointed out, the paper itself is a large part of the cost. If you use Strathmore, you drop the price quite a bit, but the desirability of the product is lower to some people.

Also, for quality, we tried many hand coating method including glass rods with rubber bands and a lot more to prove that in the long run a coating blade is best for maximum quality and maximum coated area on a given sheet. I might also add that it minimizes emulsion wast and so I can say that I use 6 ml to coat with a 4" blade and I mean 6 ml! I have seen, by count, more than 4 different methods used at EK, and the blade is the best.

But, I cannot disagree with you in what you say due to the huge range of prices.

PE

dwross
04-04-2008, 05:20 PM
Denise;

Of course there are many ways to coat and many things to coat on. I would be a fool to say otherwise. But if you stack up all of the costs you have put in to making emulsions - minus any of my blades, you would be in the $500 - $1000 range I suspect. But there is a broad price range. Just as Clarence pointed out, the paper itself is a large part of the cost. If you use Strathmore, you drop the price quite a bit, but the desirability of the product is lower to some people.

Also, for quality, we tried many hand coating method including glass rods with rubber bands and a lot more to prove that in the long run a coating blade is best for maximum quality and maximum coated area on a given sheet. I might also add that it minimizes emulsion wast and so I can say that I use 6 ml to coat with a 4" blade and I mean 6 ml! I have seen, by count, more than 4 different methods used at EK, and the blade is the best.

But, I cannot disagree with you in what you say due to the huge range of prices.

PE

Well, I feel a little silly arguing in a vacuum. I'm the only person who has tried all of the above mentioned coating techniques. I'll give you one: rubber bands on a glass rod sucks. The rubber catches and drags.

Short of an Iron Emulsionmaker Contest, someone besides the two of us need to do some comparison tests. I'm having an Open Studio on May 24 and I'll have the participants coat with a 4 inch blade, an 8 inch blade, and an emulsion well with puddle pusher, in addition to wet-coating with just a puddle pusher. That way we can get some feedback that transcends opinion.

My hope, of course, is that there turns out to be many equally fine ways to coat, including ones that you and I (and Kodak) haven't even thought of, and that folks can choose the best economics and ergonomics for their individual needs.

rmazzullo
04-04-2008, 05:39 PM
Ron,

Thank you for outlining some of the options and what some ballpark costs for equipment might be. I would very much like to see your outline discussed in greater detail in your book / DVD. While hand making emulsions are a necessary first step for me, I would like to move into more advanced areas of emulsion making, and using the technology available to me is exactly what I am going to do to get as good a result as I can, as often as I can. I have more experience in the electronic / mechanical / computer areas, and I welcome an in-depth discussion of the more technical emulsion making aspects in your book.

If you know where to look, and where to scrounge, the costs for equipment can be reduced (home built pump heads, for example). For those with access to some basic electronic and machine shop equipment, the costs could be even lower.

Thanks,

Bob M.

Photo Engineer
04-04-2008, 06:50 PM
Bob;

Thanks. I do try to get second hand equipment, but it is rather hard to get exactly what I want. I guess I have to try harder.

Denise;

I am rather amused that you say you are the only one who has used all of the above. I beg to differ with you, as I started handcoating in a class at Kodak in 1965 in which we progressed through about 5 different hand methods up through machine coating with several types of hopper. BTW, the preferred method wtih the glass rod that I mentioned in the workshop you attended is wrapping with 2 - 3 rounds of scotch tape which gives about 5 mil undercut. I showed how to measure this with a feeler guage.

The problem with a single rod, push or pull, on paper is that the paper swells when you dump on the initial slug of melted emulsion and the paper swells in the center creating a high spot of paper that is scraped clean. It therefore leaves a "V" shaped defect. The other problem with an open rod or plate is that you have to put excess emulsion down due to spread unless you create dams on the edge. This wastes emulsion. I showed these problems in class and discussed them, as they also take place when coating with the blade if you tip it , rock it, or move it across the paper with the wrong speed, or with starts and stops. Coating with the blade is an art that you develop by practicing with dyed gelatin and surfactant, and the cost of that practice goes into the cost of setting up an emulsion lab, as does every bit of waste paper, gelatin and emulsion.

And, to go back to the above about dams, if you create edge dams on the paper to prevent runs laterally, they can cause distortions as paper swells.

So I have to say that BTDT. I did 2 or more years research on many methods including brush, spray, foam applicator, glass rod and blade among others.

Regarding publications such as Wall and Baker, supposedly "open source disclosures of emulsion making", this is not true. Wall and Baker both said that they put their emulsions into the public domain but that is patently false.

In every Wall book, a critical emulsion element of one sort or another is omitted such as the gelatin grade (remember that they were using active gelatins back then and there were 3 grades available), addition time and temperature and a lot else.

Baker did much the same as Wall but less often. He was more open. That is why I suggest his book over Wall's book at my workshops. I also recommend Silver Gelatin, which is a good book but understates the utility of sulfur finish and has many untested emulsions, a fact Martin and I have discussed offline and in posts here.

The patent literature contains everything you need, but it is like having 1000 puzzles with 1000 pieces each mixed together in one box and you don't have the picture but you have to finish just one of those puzzles. The difference is that I have copies of every picture you can make for those 1000 puzzles in my head. So, I have the advantage from that point. Still, it has taken me over 4 years and the help of several friends to reach this point. I doubt if you can learn what is going on from Wall or Baker, you are merely following them by rote like reading a cookbook (a rather poor and obsolete one to boot), and parts are missing in virtually every formula.

Still, by reading Baker, I have been able to modify his high speed film emulsion to get the ISO 40 speed orthochromatic emulsion you made in class. And, I'm using it as the basis for the next jump in speed. I know which jigsaw pieces to look for because I know the picture that must be made.

I hope this additional information on coating methods and texts is useful.

PE

Emulsion
04-04-2008, 10:35 PM
Regarding buying used gear to keep advanced emulsion making costs down....

There are a large number of syringe driver type pumps that sell on e-bay. I've seen some sell for as little as US$10. Much cheaper than peristaltic pumps usually.

The syringe drivers are originally intended for slow infusion of medicines into patients. Some are listed here, these may be a starting point for pumped silver and salt for emulsion making:

http://cgi.ebay.com/Syringe-Drivers-IVAC-P1000-Volumetric-Pumps_W0QQitemZ180227865930QQihZ008QQcategoryZ3146 4QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.com/Graseby-3100-Syringe-Driver-Fully-Working_W0QQitemZ350040457821QQihZ022QQcategoryZ31 464QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Emulsion.

Kirk Keyes
04-05-2008, 01:32 AM
Emulsion - that's interesting about the syringe drivers. After spending some time recently visiting my mother, I thought about those instead of a peristaltic pump. The first issue I see is that the fastest one of the pumps you list can deliver is 200 m/hr. That's milliliters per HOUR... Not very fast. That's 3.3 mls/min. But that should work - I used my peristaltic pump to deliver 2.8 ml/min on the last emulsion I made.

Photo Engineer
04-05-2008, 09:39 AM
Regarding buying used gear to keep advanced emulsion making costs down....

There are a large number of syringe driver type pumps that sell on e-bay. I've seen some sell for as little as US$10. Much cheaper than peristaltic pumps usually.

The syringe drivers are originally intended for slow infusion of medicines into patients. Some are listed here, these may be a starting point for pumped silver and salt for emulsion making:

http://cgi.ebay.com/Syringe-Drivers-IVAC-P1000-Volumetric-Pumps_W0QQitemZ180227865930QQihZ008QQcategoryZ3146 4QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.com/Graseby-3100-Syringe-Driver-Fully-Working_W0QQitemZ350040457821QQihZ022QQcategoryZ31 464QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Emulsion.


You are absolutely correct if, as Kirk points out in his post, you get the flow range you need. These pumps fall below the range needed for normal emulsion making except for some limited cases. I'm still looking, but except for tiny volume makes of about 100 ml, these pumps will be impractical.

The range of my peristaltic pump covers all the necessary ranges I need, and I can get 2 other head types to span even greater ranges. Although, as I say, you are correct that there are less expensive ways.

In my post, I included a stirring hotplate, the coating block (sheet of 1/4" glass) and the chemicals needed. I also included brushes and glass rods rather than the coating blade, and I included extra gelatin and paper for practice purposes. I also included a scale or balance.

The hotplate and scale bring the cost up more than anything. The hotplate is needed, as most households cannot achieve the temps needed for this type of work for the times needed.

I think some people overlook some of these expenses.

PE

dwross
04-05-2008, 09:58 AM
Regarding publications such as Wall and Baker, supposedly "open source disclosures of emulsion making", this is not true. Wall and Baker both said that they put their emulsions into the public domain but that is patently false.

In every Wall book, a critical emulsion element of one sort or another is omitted such as the gelatin grade (remember that they were using active gelatins back then and there were 3 grades available), addition time and temperature and a lot else.

Baker did much the same as Wall but less often. He was more open. That is why I suggest his book over Wall's book at my workshops. I also recommend Silver Gelatin, which is a good book but understates the utility of sulfur finish and has many untested emulsions, a fact Martin and I have discussed offline and in posts here.
PE

I read an interesting article lately. It seems that over the last couple of decades, cookbooks and even the instructions on a cake mix box have become much more explicit. Fewer and fewer people have the kitchen skills and vocabulary that were once taken for granted; now every step must be spelled out. You can't just say, deglaze, reduce and add a medium roux. You can't even say 'cream the butter and add two eggs'. The instructions have to specify what 'creaming' is - what tools are required, how long it should take, and what the finished product should look like. And, "two eggs"?? Do you mean large or X-large? Should I add them with or without the shells?

I feel this is what was going on with Wall and Baker, not deliberate obfuscation. They assumed a basic skill set and vocabulary. When, in 1929, Wall wrote, "There is nothing in the literature upon the subject (photographic emulsions) which helps one much when undertaking this sort of research work. Practically all the knowledge is secreted in the great factories. The worker at this point stands practically in the position of the man who first discovered emulsion photography, and he must battle his way through and pull himself up until he has acquired a knowledge equal to what is known at the present day. This is far from a simple matter, but once I set to the task it proved tremendously fascinating", I believe him.

To stretch the cooking metaphor: The only chocolate cakes left are from a Betty Crocker box, and BC is about to close down their cake factory. Unfortunately, I still want a chocolate cake but Betty isn't sharing her recipes. Besides, you'd need a factory to make use of them. Do I give up on chocolate cake? No, damn it. I'm going to dig out grandma's cookbook, and I'm going to figure out how to cream the shortening and experiment a bit to determine egg size (or grade of gelatin, or timing of additions, or ripening temperature.) With a little luck, it may even turn out that my homemade chocolate cake is tastier than one from a box.

It is a disservice to the field to imply that only experts can do this. Regarding paper coating, I again ask you to look at this:
http://www.thelightfarm.com/Map/PaperAndCoating/MapTopic.htm

Photo Engineer
04-05-2008, 10:11 AM
Denise;

I have never said that only experts can do this. In fact the entire basis of my work has been than anyone can do it as long as they have a complete formula as a starting point.

As for Baker and Wall, they were not assuming common knowledge as the "eggs" in their case were as different as chicken, duck and goose eggs. The three grades of gelatin, common in their time, were never specified. All old Agfa and Kodak formulas, regardless of the level of the operator specified soft, medium or hard gelatin, or specific blends. Wall for the most part just left out critical information, and there is no way around this as assumptions about addition time and temperature will make totally different emulsions from several of his examples. There is no simple way to figure this out by some sort of "common knowledge".

I have 3 formulas that are virtually identical, but if I omitted just one item from any of them, no one could duplicate my work and only a very very advanced emulsion chemist might guess the right answer. I don't intend for my formulas to be that way when published. I will give all details so that anyone can do it, and I will give reasons for the details and what can be expected if you change these details, just as I gave at the workshop.

PE

Photo Engineer
04-05-2008, 10:35 AM
In the reference given by Denise in one of the posts above, she shows the wrinkling of paper depending on the orientation of the "warp and woof". Yes, of course, paper has a grain and cross grain much like fabric in analogy and this can cause problems.

To minimize or eliminate this, I teach my students to coat between 7% and 10% gelatin at about 100 - 110 F, onto a surfact at 65 - 75 deg F. This allows the emulsion to begin cooling rapidly by contact with cool support, and also by evaporative cooling into the room atmosphere. It minimizes the expansion and buckling of the paper, and it speeds the chill setting of the gelatin.

In this way, you get a smooth coating that you can quickly lift from the coating block. I demonstrate how the gelatin changes from glossy to matte in appearance under the safelight, and also caution the student not to touch the under surface of the paper with their fingers. Body heat will melt the gelatin again and cause buckling of the paper.

As I said, hand coating is an art form. I have boxes of test coatings here made while I practiced with all of the hand coating methods, and I built a puddle pusher with a well too. Some of my bad examples and the good stuff has already been taped for the DVD, and the slide show sticky in this forum on "how I make and coat emulsions" shows some examples of test coatings.

The only proof of this that I can offer is the uniformity of the coatings that I sent to those who have tested my paper for themselves. I have sent them full sheets of 11x14 with a good center of 8x10. If I coat 11x14, I use paper of about 16x20 to get a good 11x14 center and etc. Oh, well, the pictures in the slide show on youtube also offer evidence as will the DVD shots.

PE

bdial
04-05-2008, 11:13 AM
PE,
Apparently the hotplate you refer to is not the garden variety household gadget that one could buy at a house goods store?

Photo Engineer
04-05-2008, 11:15 AM
It could be. There is no reason why not as long as you control the temperature well during a make or a sensitization. This will cut cost considerably but will require more operator attention is all.

The one I have includes a magnetic stirrer and a thermostatic control. It was done for my convenience and for accuracy.

PE

dwross
04-05-2008, 12:33 PM
As for Baker and Wall, they were not assuming common knowledge as the "eggs" in their case were as different as chicken, duck and goose eggs. The three grades of gelatin, common in their time, were never specified.

Ron,
If you're going to tell me I need goose eggs to bake a tasty chocolate cook, I'm going to be really disappointed :).

In reality, we don't have all the materials available to us that Abney, Wall, Eder, and Baker had. I use the Hard (250 Bloom) gelatin from Photographers' Formulary for all my work. It is inexpensive, consistent, and likely to be around for awhile.

What we do have is a lingering knowledge and love of beautiful b&w photographs. We can do this. As much as anyone else, I look forward to your contributions. But, since you've as much as said you're not planning any more workshops and we don't know the release date of your DVD and book, or what will be in them, and what will have entered the private sphere, I'm sure you won't be offended if some of us bumble through, having the time of our lives.

With warmest regards and greatest respect,
Denise

Photo Engineer
04-05-2008, 12:42 PM
Denise;

Have all the fun you want. I will give workshops, just not this year due to consulting work and other family obligations.

I am also trying to develope a level II workshop that takes off where the last one ended.

The DVD will include material from your workshop and level II which I have been working on right now for some of the consulting work. I have permission to share the work after I finish, and I have alluded to part of it regarding UF and pump work.

As for eggs, a friend raised ducks and I ended up with a dozen duck eggs. We loved scrambled duck eggs, so one day we substituted duck eggs for chicken eggs in oatmeal cookies. It was a total disaster! This goes to show what can happen in emulsion making.

Wall and Baker used active gelatin, and so any formula that I use of theirs must be reformulated to use a sulfur treatment as I do with the ISO 40 emulsion and I do with the enlarging paper emulsion I posted. This takes the experimentation, trial and error to give you a formula that is pretty much fool proof. I had to make that enlarging emulsion at least a dozen times in tiny batches to get the exact proportion of thosulfate to emulsion along with time and temperature. You expressed surprise at the time and temperature (60 C for 60 mins), but I did all of them from 50 - 60 deg C and 30, 45, 60 and 90 mins. I also did a series of iodide additions. So, what I post is the final result of those dozens of experiments.

The enlarging paper emulsion is not from Wall or Baker, it is my own from scratch.

Have fun.

PE