Availability of different Liquid Emulsions.

[Photo Engineer]

Ryuji, the details of mixing during making of emulsions is a subject off-limits to me for this discussion.

As for the mention of injecting silver though, I do use relatively high pressure with short times and high mixing rates. This is known in the literature and there have been patents and discussions about it.

You may be interested in the novel methodology suggested by Wey and Whiteley in their US patent. I'm sorry but I don't have the reference at hand. I'll post it later if I can find the number.

Your published approach is also from the same era and looks much like Kodak publication AJ-12 as I said in another post. You surely have more modern versions but I have not seen them, and I wouldn't think of commenting on them without trying them out.

I make my emulsions in 120 or 220 gram batches and divide them into 30 g portions for easy breakdown for finish and doctoring experiments. So, for 10 makes of even 120 grams, this is 30 experiments and for 220 gram makes that is 60 experiments.

PE

 

[Ryuji]

Wey's work is classic. I've read the original reports and I'm familiar with his work, as far as published results are concerned.

I'm happy to post one of t-grain emulsion formula if you have a triple jet apparatus and suitable gelatins. Here's whet I remember top off my head right now.

I use oxidized phthalated gelatin in kettle at 35C for nucleation, and bring the temperature up to 70C for ripening, then growth. Just before and during growth stage phthalated gelatin is added in addition to Ag and X. The third jet controls the iodide shell and incorporation of dopants. Ripener is used for negative emulsions during the growth stage.

The Ag and X jets in nucleation stage is 0.1M and 0.2M, respectively, while pBr is 1.5 and gelatin in the kettle is 0.5%. The jets are 1M and 1.2M during growth, at pBr of 1.0, and gelatin in the kettle is 2.0%. If pBr is too low, contrast lowers. The kind of gelatin, as well as the gel concentration have large influence on aspect ratio of t-grains.

After growth, I desalt by coagulation method. Digest S for paper, S+Au for negative (R sensitization is done in the interior of the grains for negative emulsions). Add sensitizing dye and allow time for adsorption at this stage. Then stabilize with TAI, PMT and pBr, pH adjustment. Add a biocide and cool for storage.

For negative emulsions I blend 3 emulsions after all above steps are performed. These 3 emulsions receive different growth and digestion steps, but they are otherwise similar.

Ryuji, the details of mixing during making of emulsions is a subject off-limits to me for this discussion.

As for the mention of injecting silver though, I do use relatively high pressure with short times and high mixing rates. This is known in the literature and there have been patents and discussions about it.

You may be interested in the novel methodology suggested by Wey and Whiteley in their US patent. I'm sorry but I don't have the reference at hand. I'll post it later if I can find the number.

Your published approach is also from the same era and looks much like Kodak publication AJ-12 as I said in another post. You surely have more modern versions but I have not seen them, and I wouldn't think of commenting on them without trying them out.

I make my emulsions in 120 or 220 gram batches and divide them into 30 g portions for easy breakdown for finish and doctoring experiments. So, for 10 makes of even 120 grams, this is 30 experiments and for 220 gram makes that is 60 experiments.

PE

 

[Photo Engineer]

Ryuji, I'm sure it is a fine emulsion, but very complex. There are simpler and better ways to do what you are doing that are much more modern. There are also much more complicated and better ways to do this as well. It depends on your final aim.

If you look at the figure posted on Bruce Kahn's web site, you may get an idea of how complex the plumbing and electronics can get for a modern making station. That figure of his of course, is for a dual jet emulsion. In reality there are many more addition stations than even you mention above and more than he depicts in the 'real world'. Several can be in action at one time.

I'm also surprised at some of the steps you leave out and the methodology of adding ripener. It will work, I'm sure, but again I would do it differently.

The pBr is really pI since Iodide is present, so wouldn't it be better to report pAg? And how do you control pAg or whatever you measure? If the pAg varies, it may be due to iodide or bromide depending on addition method and unintentional solution flow rate fluctuations. What is your reference electrode plated with? Or is it plated at all?

Be careful of placement of inlet orifices. Positioning errors can give different pAg values depending on inlet spacing and mixer rate as well as electrode type. This emulsion will probably be difficult to scale up or down due to mixing problems. Just as an offhand suggestion you may want to make a 2x batch or a 4x batch to see if it still works.

The use of Phthalated gelatin will reduce the maximum grain size attainable at any given temperature, IIRC, but then it has been quite a while since anyone used that at Kodak or Fuji. I think phthalated gelatin was abandoned before T-grain technology.

I'm surprised you are not doing UF washing by now.

I see no provision for acid or base adjustment during the make. Of course, using phthalated gelatin this is impossible to implement, and that is too bad, as it would improve the emulsion in all probability. This is one of the major advantages of UF washing and one of the major disadvantages of using PA gelatin. There is a way around it, but you didn't mention it, so I guess you don't want to use acid and base adjusts.

I am avoiding T-grains, as they look and act too modern. I'm working with K-Grain technology.

PE

 

[Ryuji]

Ron, when are you going to stop talking nonesense about things you really don't understand in an effort to imply you are always right and the smartest on the internet? I'm sick of your arbitrary stories you make up when you don't know real answers already exist and they are known to others. What's ironic is that much of the real answers were worked out by people from Kodak Research Labs in Rochester, where you repeatedly claim that you know most of findings in both public and secrecy.

Oxidized gelatin and phthalated gelatin are useful colloids in preparation of tabular grains of high aspect ratio. Both of these gelatins have less restraining action and indeed make larger grains while other conditions are fixed and when compared to regular inert gelatin, so what you said about grain size does not make sense at all. This is the kind of work done by Maskasky at Kodak Research Lab and I thought you knew all about what was done at the KRL. It's surprising that you didn't know that.

You are very confused about pBr, pI and pAg. They are all related to each other by a set of equations. In modern negative emulsions iodide is added in a highly concentrated form in a rather brief time as one of the shell layers. The core is bromide, and the outermost shell is also bromide. During nucleation there is usually no iodide at all, as presence thereof results in lower aspect ratio. pBr is most important in this stage to maximize the probability that a crystal will possess two twinned planes. Ripening is used to remove non-t-grains before growing the crystals. A lot of particular aspects of my emulsion making are designed so that the emulsion is mostly consisting of one kind of crystal habit.

Ryuji, I'm sure it is a fine emulsion, but very complex. There are simpler and better ways to do what you are doing that are much more modern. There are also much more complicated and better ways to do this as well. It depends on your final aim.

If you look at the figure posted on Bruce Kahn's web site, you may get an idea of how complex the plumbing and electronics can get for a modern making station. That figure of his of course, is for a dual jet emulsion. In reality there are many more addition stations than even you mention above and more than he depicts in the 'real world'. Several can be in action at one time.

I'm also surprised at some of the steps you leave out and the methodology of adding ripener. It will work, I'm sure, but again I would do it differently.

The pBr is really pI since Iodide is present, so wouldn't it be better to report pAg? And how do you control pAg or whatever you measure? If the pAg varies, it may be due to iodide or bromide depending on addition method and unintentional solution flow rate fluctuations. What is your reference electrode plated with? Or is it plated at all?

Be careful of placement of inlet orifices. Positioning errors can give different pAg values depending on inlet spacing and mixer rate as well as electrode type. This emulsion will probably be difficult to scale up or down due to mixing problems. Just as an offhand suggestion you may want to make a 2x batch or a 4x batch to see if it still works.

The use of Phthalated gelatin will reduce the maximum grain size attainable at any given temperature, IIRC, but then it has been quite a while since anyone used that at Kodak or Fuji. I think phthalated gelatin was abandoned before T-grain technology.

I'm surprised you are not doing UF washing by now.

I see no provision for acid or base adjustment during the make. Of course, using phthalated gelatin this is impossible to implement, and that is too bad, as it would improve the emulsion in all probability. This is one of the major advantages of UF washing and one of the major disadvantages of using PA gelatin. There is a way around it, but you didn't mention it, so I guess you don't want to use acid and base adjusts.

I am avoiding T-grains, as they look and act too modern. I'm working with K-Grain technology.

PE

 

[Photo Engineer]

Ryuji, oxidized gelatin yes, PA gelatin not much at all. It prevents some operations that requre acid - base shifts during the make. If used, it is at low conversion levels to prevent acid - base shift related problems.

The measure of pX or pAg is not accurate enough for this type of work. Iodide is usually run in slaved to silver and bromide is run in control with proper control equipment and proper measuring devices with appropriate electrodes. Somtimes other methods are used to control halide addition.

If your emulsion is a T-grain, I hope it avoids all current patents for both making technology and aspect ratio. Both are patented.

Yes, I am aware of the work of Maskasky, Daubendiek, Marchetti, Perry, Wey and Whiteley to name a few. I simply cannot discuss it in detail.

And, if my work does not bother you then why the continuation of this thread? Why start it at all? Why pick at my work? I feel that you are doing good work - albeit complex, and have no issues with what you are doing. I simply have different goals than you do, and know a lot that I cannot disclose and so walk a knife edge in my discourse here and in the work I do in my own darkroom.

I could write several paragraphs on measurment of pAg and variants, and several on mixing, but these are really off-limits. I could do the same for addition methodology, again it is off limits. I could discourse for hours on mathematical modeling of pAg with different halides, another off limit subject. How about emulsion scaling models. I know a lot about that as well. All of this is off limits as far as I'm concerned.

As for techniques, yes there are better emulsions but I choose to pick simple ones. Yes, there are a lot of ways to sensitize, and I have done most of them here or at Kodak. My raw and sensitized emulsions do very well. Out of the can the AgBrI has a raw speed of ISO 25. After sulfur sensitization and spectral sensitization I will probably get a lot more, but lose some to antifogging / stabilization, and addition of acutance dyes for sharpness. I hope for ISO 25 but may get as high as 100. That is my hope. I hope to do it with simple emulsions with no fancy equipment and no long making or sensitization steps.

I commend you for your diligent and good work. I hope that people are interested in it and I hope you can avoid patent infringement. I'm sure that there will be people interested in your work. I hope that perhaps some people will be interested in my work as well.

My comments above regarding your T-grain make were intended to show merely that there are many possible ways to do the same thing. T-grains are made at all major manufacturers plants and each manufacturer uses different methodology. I did not intend those comments to be taken as negative in any way. After all, if it works, it works.

PE

 

[Ryuji]

Ron, you're doing nonesense again. It's obvious that you don't keep up with the technology or ignoring all the updates since you retired, and making up stories to satisfy your desire of being the smartest guy in online discussion forums. And you're also distorting facts just to stubbornly maintain your contention "valid." But that is hugely misleading people who are trying to learn how to make silver gelatin emulsions.

You are way off about phthalated (or acylated in general) gelatins. Phthalated and trimellitiated gelatins are used in making tabular grain emulsions as disclosed in Japanese unexamined patent applications Heisei 8-82883 and 10-148897. I am sure that KRL people read Japanese patents so they must be aware of this technology but obviously all of these happened after you retired.

I could go on for other issues with specific info and necessary details, but there's really no point in doing this, since you'll come back like "you're wrong," "there are better ways to do this," "Kodak figured all that out decades ago," and so on. Let's cut all that crap. You often go too far to speak highly of Kodak and create unfounded stories to give bad images to its competitors, but your postings are not doing any good to photography or Kodak at all. It's only hurting your credibility.

Your emulsion work doesn't bother me at all. In fact, based on what I heard from someone, I don't even think you've gone as far as you have claimed. But your nonesense bothers me and other people (I get direct emails about this thread and other posts by Ron Mowrey and "Photo Engineer."). I seriously suggest that you don't write about things you really don't know. Also if you don't want to admit and correct your mistakes when ones are found, you shouldn't be writing anything at all. Once written, anything has some chance of having it later found to be wrong.

Ok, this is my last post here.

Ryuji, oxidized gelatin yes, PA gelatin not much at all. It prevents some operations that requre acid - base shifts during the make. If used, it is at low conversion levels to prevent acid - base shift related problems.

The measure of pX or pAg is not accurate enough for this type of work. Iodide is usually run in slaved to silver and bromide is run in control with proper control equipment and proper measuring devices with appropriate electrodes. Somtimes other methods are used to control halide addition.

If your emulsion is a T-grain, I hope it avoids all current patents for both making technology and aspect ratio. Both are patented.

Yes, I am aware of the work of Maskasky, Daubendiek, Marchetti, Perry, Wey and Whiteley to name a few. I simply cannot discuss it in detail.

And, if my work does not bother you then why the continuation of this thread? Why start it at all? Why pick at my work? I feel that you are doing good work - albeit complex, and have no issues with what you are doing. I simply have different goals than you do, and know a lot that I cannot disclose and so walk a knife edge in my discourse here and in the work I do in my own darkroom.

I could write several paragraphs on measurment of pAg and variants, and several on mixing, but these are really off-limits. I could do the same for addition methodology, again it is off limits. I could discourse for hours on mathematical modeling of pAg with different halides, another off limit subject. How about emulsion scaling models. I know a lot about that as well. All of this is off limits as far as I'm concerned.

As for techniques, yes there are better emulsions but I choose to pick simple ones. Yes, there are a lot of ways to sensitize, and I have done most of them here or at Kodak. My raw and sensitized emulsions do very well. Out of the can the AgBrI has a raw speed of ISO 25. After sulfur sensitization and spectral sensitization I will probably get a lot more, but lose some to antifogging / stabilization, and addition of acutance dyes for sharpness. I hope for ISO 25 but may get as high as 100. That is my hope. I hope to do it with simple emulsions with no fancy equipment and no long making or sensitization steps.

I commend you for your diligent and good work. I hope that people are interested in it and I hope you can avoid patent infringement. I'm sure that there will be people interested in your work. I hope that perhaps some people will be interested in my work as well.

My comments above regarding your T-grain make were intended to show merely that there are many possible ways to do the same thing. T-grains are made at all major manufacturers plants and each manufacturer uses different methodology. I did not intend those comments to be taken as negative in any way. After all, if it works, it works.

PE

 

[Photo Engineer]

Ryuji, I don't think that there is any reason for us to argue. You can call me any time you want. I think we should be working together.

I would be delighted to help you with your work and I would be happy to accept your comments on mine.

You know how to reach me.

PE

 

[Ray Rogers]

Really Ron... who in his right mind would want to work with such a pain in the grass as this!

But your politeness is superior to mine. I cannot sit by and let his insults go free.

Ryuji insultingly writes:

I seriously suggest that you don't write about things you really don't know. Also if you don't want to admit and correct your mistakes when ones are found, you shouldn't be writing anything at all. Once written, anything has some chance of having it later found to be wrong.

Hey Ryuji,
I see you have changed your stance on use of rapid acting hardeners at the end of a make that you for years worked over with surficants and polymers to get everything perfected...

Goes to show how accurate your statement about having to watch what you say is!

Since you admit to following the patents of very recent dates, you have drawn the attention of everyone whos interested in this. I thought your intention was to make something for the little guy, the guy working on his kitchen table? The guys in the legal department must be salivating, Pavlow! Get this dog drooling out of here!

Ron I commend you and your ability to maintain civility and keep a straight face in the middle of all this.

I belive what we are seeing is an incurable case of "Teacheritus"

Don't waste your time dealing with his insults. They reflect ONLY his personality and NOTHING else.

I make VERY good emulsions myself, but I am wise enough to know that everyone can have good ideas and I am not too proud to learn from anyone.

So far however, Ryuji has had nothing of value to offer, in my opinion (and I HAVE seen some of his emulsions).

You on the otherhand do, and I wholeheartedly encourage you to write!

The content value of your writing far exceeds that of Ryuji's (naturally!) despite the fact that Ryuji SOUNDS more authoritative... We both know it is slight of hand, pure illusion!

Some people talk of not buying KODAK film products anymore out of anger for KODAKs decision to abandon traditional materials, well,
I for one would not support Ryuji NO MATTER HOW GOOD HIS EMULSION BECOMES...

If I could not produce good emulsions myself, I would support your work.

Otherwise, I would learn to draw! Or go dig....

Ray Rogers

 

[gbroadbridge]

I have to say, having read the entire thread, I believe and stand by Photo Engineer.

Graham.

 

[Nicole]

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