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gainer

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The oxidation of hydroquinone in the presence of sodium sulfite results in an increase in pH. Where did you find the information that dehydroascorbic acid is converted to ascorbic acid by sulfite? I have not seen that anywhere. In addition, none of my ascorbate developers contain sulfite. Since both ascorbic acid and hydroquinone form HBr and HI in equal amounts for equal density produced, and these acids are neutralized equally if alkalinity of the solutions are the same, the only remaining thing that can cause a difference in pH is the fact that dehydroscorbic acid is lower in pH than the oxidized hydroquinone, which is seldom used without sulfite. You did not explain away Ryuji's assertion that the products of development by ascorbic acid are lower in pH than those of decelopment by hydroquinone. If you are so convinced, do the experiment to prove your assertion.
 
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Kirk Keyes

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gainer said:
Since both ascorbic acid and hydroquinone form HBr and HI in equal amounts for equal density produced, and these acids are neutralized equally if alkalinity of the solutions are the same, the only remaining thing that can cause a difference in pH is the fact that dehydroscorbic acid is lower in pH than the oxidized hydroquinone, which is seldom used without sulfite. You did not explain away Ryuji's assertion that the products of development by ascorbic acid are lower in pH than those of decelopment by hydroquinone.

From: http://silvergrain.org/Photo-Tech/ascorbate-dev.html
"The oxidation products of hydroquinone (ones that are exhausted after developing reaction) is alkaline. This may accelerate development in the area surrounding areas of intense development reaction. On the other hand, the oxidation products of ascorbates are acids, potentially inhibiting development in areas nearby the site of intense reaction. This means that ascorbates are more desirable when adjacency effect and compensation effect are sought."

You mean this assertion?

That's fine and all, but let's get back to developers like Pyrocat and their possible behavior as the buffer changes concentration.
 

sanking

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Kirk Keyes said:
From: http://silvergrain.org/Photo-Tech/ascorbate-dev.html
That's fine and all, but let's get back to developers like Pyrocat and their possible behavior as the buffer changes concentration.



Kirk,

There are two things that I am absolutely certain of about Pyrocat-HD, and it may apply to other similar two part developers.

1. Apparent sharpness, which I assume to be from edge effects, is least with strong dilutions and greatest with very weak dilutions.

2. For any given dilution, within a range of 2:2:100 to 1:1:400, apparent sharpness is greater with minimal and extreme minimal agitation than with constant agitation as in rotary. Very extreme adjacency effects are not reached until we reduce the number of agitation cycles to one (stand) or two (semi-stand).

The question is, are these differences due to buffer change concentration or some other mechanism, such as exhaustion of the reducer, or perhaps they work together.

I am also certain that with long development times using weak dilutions oxidation and development of general stain is decreased by using more Stock A than Stock B, and increased by using more Stock B than A.

Sandy
 

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Quote by Gainer: "Since both ascorbic acid and hydroquinone form HBr and HI in equal amounts for equal density produced, and these acids are neutralized equally if alkalinity of the solutions are the same, the only remaining thing that can cause a difference in pH is the fact that dehydroscorbic acid is lower in pH than the oxidized hydroquinone, which is seldom used without sulfite. You did not explain away Ryuji's assertion that the products of development by ascorbic acid are lower in pH than those of decelopment by hydroquinone."

Patrick, until you understand the difference between pH and buffer capacity this is a useless contention. At 1:100 dilution the pH may be the same as in the stock solution, but the buffer capacity is at 1/100th the level.

I see that you ignored my suggested calculations. This may help explain a lot to you. After you go through them, I will post additional information. The math is trivial.

I have no comment on Ryuji's work either way. As Kirk said, this is talking about dilute Pyrocat-HD developers.

I gave the reference to the reaction of dehydroascorbic acid in my post above. It is well known. In any event, the DHAA is a weak acid when faced with HBr at the concentrations found in the developing film. If you would just give my calculations a try, you would see that.

PE
 
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Kirk Keyes

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Photo Engineer said:
If you would just give my calculations a try, you would see that. PE

Ok. Here's what I get from your setup.

"Calculate the moles per square meter of HBr released in this volume and then calculate the amount of Na2CO3 present and ascorbate present if the carbonate is at 50 g/l and the ascorbate is at 5 g/l."

The HBr is equal to AgBr assuming 100% reaction, so that gives 0.01065 mole HBr/m^2. With the thichness of 0.05mm, that gives a volume of 50 ml for that 1 m^2 sheet of film.

So now are you assuming the CO3= will go into that 50 ml of emulsion at a concentration of 50g/L. That's 0.833 mole/L which means there is 2.5 g CO3= in the 50 ml of emulsion, or .04165 mole CO3= total in the emulsion. That's 3.9 times more moles of CO3= than HBr, or H+ from the acid. And of course, we now need to go to normality, and there is 7.8 more equivalents of CO3= than the H+ from the HBr.

For Ascorbate, 5g/L gives 0.0257 mole/L which gives 0.00143 mole in the emulsion. There's 7.6 times more HBr in the emulsion than there is ascorbate in the emulsion from the solution. (This assumes they all stay there during the development, no diffusion of H+ or Br-, or the other compounds in solution)

This all assumes that the carbonate and ascorbate can dissolve into the emulsion at the same concs that they are on the solution (i.e the gelatin has no volume in the swelled emulsion?).

One thing to remember is that 50 g/L CO3= is pretty strong for any developer, at least for a "stand" developer. The Pyrocat will be much less - 20 mls of 75% K2CO3 per litre at a 1+1+100 dilution. 2 or more times less for what people are using in stand developers. You'll not have an excess of CO3= in those solutions. And much less hydroxide for people using Rodinal.

Of course, the HBr will actually not reach the concs discussed above in your example due to diffusion as it is not all developed at the same time, but that brings me back to my original point - a stronger buffer may help speed the "stand" process along and it should allow less time for the HBr to diffuse out or fresh buffer to diffuse in...

And that's why I'm guessing the this approach should help with the kinetic gradient to use for increasing the edge effects.
 
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Kirk Keyes

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sanking said:
There are two things that I am absolutely certain of about Pyrocat-HD, and it may apply to other similar two part developers.

1. Apparent sharpness, which I assume to be from edge effects, is least with strong dilutions and greatest with very weak dilutions.

2. For any given dilution, within a range of 2:2:100 to 1:1:400, apparent sharpness is greater with minimal and extreme minimal agitation than with constant agitation as in rotary. Very extreme adjacency effects are not reached until we reduce the number of agitation cycles to one (stand) or two (semi-stand).

The question is, are these differences due to buffer change concentration or some other mechanism, such as exhaustion of the reducer, or perhaps they work together.

I am also certain that with long development times using weak dilutions oxidation and development of general stain is decreased by using more Stock A than Stock B, and increased by using more Stock B than A.

Your Point 2 is certainly expected. Restraining the flow of fresh developer in to the film by reducing agitation is understandable. It's also understandable your observations about overall stain as the ratio of A & B change.

Point 1 - "Apparent sharpness, which I assume to be from edge effects, is least with strong dilutions and greatest with very weak dilutions"

And these dilutions you are refering to here have the same ratio of parts A & B?

I guess it's a matter of getting past the general stain to see if the edge effects have been increased?

If one is willing to accept longer expsoure times, then there may be merit in the idea. As Patrick says, I guess some actual tests need to be done to see if that happens. I guess I need to add that to my ever increasing list of things to try out some day!
 

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Kirk, you have the essentials written down here very well.

The actual situation is as you describe, but swell starts from zero and could go up through as much as 0.2 mm not just 0.05 mm, and therefore you need to integrate dV/dT or volume with respect to time, and dC/dT or concentration wrt time. These sets of integrals describe difffusion in and out of the coating and therefore have both plus and minus values. There are several other terms that must be used in this type of evaluation, but it would be useless to continue with this here.

I was conservative in silver spread as well. It may be that a given film has twice the silver coated than I describe above.

In essence, in a dilute developer where the buffer capacity is low, or in a hydroxide developer where the buffer capacity is low, the pH drops and begins to contribute to edge effects in two ways. One is bromide ion effects and the other is hydrogen ion effects. It is difficult to distinguish between them.

The ascorbate, HQ, metol, whatever developing agents.. are present in small quantities mole wise to start with and can slow development by further dilution. Very often, they recycle by using the sulfite as an exchange medium, oxidizing sulfite to sulfate, or in the case of quinone, reacting directly to form the HQ monosulfonate. In any event, developer exhaustion can also contribute to edge effects. Interesting? I think so.

Therefore, all the obfuscation aside, your question is quite valid and with merit. The buffer capacity, not the pH may be quite significant in these very dilute developers, and is exaggerated by stand and semi-stand development. Developer concentration and ratios of the developing agents may be critical.

Since bromide drag is known to take place, we know diffusion is a significnat contributor to this situation. The difference is that the pH effect is more of a spread than a drag, ie, it spreads out more uniformly due to the diffusion effects of hydrogen ion being faster and more uniform. It is also more subtle. This also becomes a part of the integrals mentioned above.

Just as an aside, in color materials pH effects layerwise are an additional source of interimage effects due to alkali consumption of adjacent layers 'sucking' up or 'pushing out' byproducts such as hydroxide ion and hydrogen ion respectively.

This work has been published by researchers such as Kai Liang and Roland Willis in separate articles describing diffusion models and kinetics of development.

I apologize to all who don't like science, but sometimes it is good to get a healthy dose of reality to go with the 'black magic' that some people supply regarding photographic processes. It is a real science where math, chemistry, and physics meet head on.

The bottom line is that the dilute developers are on the verge of alkali starvation and developer starvation and this may introduce unpredictable effects akin to halide drag. This will vary from film to film due to halide content and silver content.

Careful examination of these types of developers and dilutions may reveal unique optimum formulas for given conditions of time, agitation or film type.

I hope this is a suitable explanation and help for you all.

PE
 

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Kirk Keyes said:
Point 1 - "Apparent sharpness, which I assume to be from edge effects, is least with strong dilutions and greatest with very weak dilutions"

And these dilutions you are refering to here have the same ratio of parts A & B?

I guess it's a matter of getting past the general stain to see if the edge effects have been increased?

Until recently virtually all of my testing was done with equal ratios of Parts A and B so most of my observations about sharpness at various dilutions presume equal ratios.

I began recommending assymetrical ratios of Parts A and B about a year ago, for two situations: 1) rotary processing of thick emulsion films that tend to stain a lot, such as BPF 200, HP5+, BPF, TRI-X, etc. and for other high speed films, including HP5+ and JandC Classic 400 (Fortepan 400), and 2) when using very dilute solutions for minimal and stand develoment. Both solutions were designed to reduce B+F or general stain.

I have not done enough comparative testing to know at this point how the use of assymetrical ratios impacts sharpness. Hopefully PE or someone else will provide us soon enough with working directions for an affordable system that will allow us to conveniently test accutance.

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I'd like to bring this topic down several notches for a minute from the highly scientific and technical to the very basic and practical.

Is this procedure (and ratios/agitation schemes) similar for silver as well as alt(platinum) and AZO or do these latter two require a different strategies?

Thanks
 

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Daniel Grenier said:
I'd like to bring this topic down several notches for a minute from the highly scientific and technical to the very basic and practical.

Is this procedure (and ratios/agitation schemes) similar for silver as well as alt(platinum) and AZO or do these latter two require a different strategies?

Thanks

Yes, it is just as appropriate for regular silver printing as for AZO and alternative processes.

I appreciated all of the scientific comments, but in reading through them I am reminded of a quote by Albert Einstein, to wit:

"Not everything that can be counted counts, and not everything that counts can be counted."

Sandy
 

gainer

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sanking said:
Yes, it is just as appropriate for regular silver printing as for AZO and alternative processes.

I appreciated all of the scientific comments, but in reading through them I am reminded of a quote by Albert Einstein, to wit:

"Not everything that can be counted counts, and not everything that counts can be counted."

Sandy
Add to that the theorem of his friend, Kurt Godel: Any set of axioms at least as rich as arithmetic is either incomplete or inconsistent.
 

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Einstein also said "I cannot believe that God plays dice with the universe". He believed that there were certain fundamental rules in all areas of scientific endeavor.

His very good friend, Arnold Weissberger, was an outstanding photographic engineer at Eastman Kodak, and the author of many papers, patents, and textbooks on chemistry and photography. Arnold's son Ted was also a photographic engineer at Eastman Kodak.

What does this prove? Well, they all had faith in science, and the Weissbergers believed that there was such a thing as photgraphic science and stuck with it through two generations. To them, it wasn't hand waving or guesstimation.

It also may prove that very few but Kirk understood the point of buffer capacity and dilution effects on developers from that little math exercise above. It is truly something that can be counted and enumerated. Remarks like those made above will not make the science involved vanish nor will it help us reach accord or mutual understanding.

PE
 
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Kirk Keyes

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Photo Engineer said:
It is truly something that can be counted and enumerated. Remarks like those made above will not make the science involved vanish nor will it help us reach accord or mutual understanding.

Amen, brother.
 

gainer

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Photo Engineer said:
Einstein also said "I cannot believe that God plays dice with the universe". He believed that there were certain fundamental rules in all areas of scientific endeavor.

His very good friend, Arnold Weissberger, was an outstanding photographic engineer at Eastman Kodak, and the author of many papers, patents, and textbooks on chemistry and photography. Arnold's son Ted was also a photographic engineer at Eastman Kodak.

What does this prove? Well, they all had faith in science, and the Weissbergers believed that there was such a thing as photgraphic science and stuck with it through two generations. To them, it wasn't hand waving or guesstimation.

It also may prove that very few but Kirk understood the point of buffer capacity and dilution effects on developers from that little math exercise above. It is truly something that can be counted and enumerated. Remarks like those made above will not make the science involved vanish nor will it help us reach accord or mutual understanding.

PE
You are still young. Someday you will learn.
 

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Patrick, to paraphrase Oliver Cromwell, 'I beseech thee to consider .. that you may be in error'. I can make personal comments too.

Perhaps you are too old to learn something new. Or, perhaps you don't want to consider the possibility suggested by Cromwell.

It seems to me that rather than test the mathematical argument above regarding buffer capacity or the effects of 1:100 dilution, you rather turn to these personal comments.

Shakespeare had a quote for this type of situation as well, paraphrased here 'methink he protesteth too loudly'.

PE
 

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"The Lady doth protest too much, methinks" wasn't a quote by Shakespeare, it was spoken by one of his characters. Be careful who you quote: you are in fact quoting a woman who married the murderer of her first husband in order to maintain the lifestyle to which she had become accustomed and who finds a simple proclamation of innocence unbelievable, prompting her observation.

Hardly a person to inspire confidence in her opinions... :wink:

Cheers, Bob.
 

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Bob, I know the reference, and that is why I said 'paraphrase'. The Cromwell quote also includes more as well which is why I used 'paraphrase'. Thanks.

I should have said 'a paraphrase from Shakespeare'. I didn't have my works handy and besides, I don't have the complete Shakespeare, just excerpts. Instead when I had a chance to buy it, I chose the complete works of Conan Doyle. I find him more readable. Besides, I had to memorize too much Shakespeare in HS. It wore me down too much. "Tomorrow and tomorrow creeps in this petty pace from day to day.....". (this is singularly appropriate as I await another comment on this thread) At one time, I could probably recite half of the lines in most of his plays. Or is that most of the lines in half of his plays.

I put the evening to good use, coating and testing new emulsion experiments to thwart the onslaught of d***tal photography rather than just sit here and wait for these nice posts.

PE
 

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I wasn't correcting your paraphrase (I merely quoted the original in case others did not recognise it). My point was that people quote from Shakespeare and treat such sayings as if they have some special provenance without taking in to account who actually said them in the play. Another favorite people use is: "Neither a lender nor a borrower be" - ignoring the fact that it was said by the pompous old windbag Polonius...

I shall leave you all now to continue discussing things of which I understand about 50%.... on a good day...

Cheers, Bob.
 

gainer

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Photo Engineer said:
Patrick, to paraphrase Oliver Cromwell, 'I beseech thee to consider .. that you may be in error'. I can make personal comments too.

Perhaps you are too old to learn something new. Or, perhaps you don't want to consider the possibility suggested by Cromwell.

It seems to me that rather than test the mathematical argument above regarding buffer capacity or the effects of 1:100 dilution, you rather turn to these personal comments.

Shakespeare had a quote for this type of situation as well, paraphrased here 'methink he protesteth too loudly'.

PE
I was thinking that someday you would understand the scientific method. It is not what it appears that you think it is. I learn new things every day. The quote by Sandy King of Einstein and the Incompleteness Theorem of Godel I mentioned are related. Sooner or later you will find that your so called science will lead you to a self contradiction or an absurdity. Furthermore, we cannot fully describe nature by axioms and formal logic. We may, in fact, know everything there is to know except the fact that we know it.

Science is knowledge, however it is obtained. I have seen too many cases where the theories by which we attempt to order this knowledge have been mistaken for the knowledge itself. The most glaring I can remember was a misuse of aerodynamic theory by professors of a prestigious university who did not take the trouble to see that the particular wind tunnel data they questioned was not within the range of the theory they were using. If you keep your eyes open, you may find some examples for yourself. Be careful you do not make them.

The arguments about the effects of 1:100 dilution or buffer capacity are your arguments. Why don't you test them? I have my own hypotheses to test. In what I have done so far, I have found that dilution alone is not necessary for stand development, nor for very good sharpness, provided one starts with the right developer.
 
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Kirk Keyes

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gainer said:
The arguments about the effects of 1:100 dilution or buffer capacity are your arguments. Why don't you test them? I have my own hypotheses to test.

Patrick - I in no way was asking you (or anyone else here) to test my hypothesis when I posted this thread. I was merely looking to see if someone else hade already made a similar observation. I think that this is similar to what is often referred to as "researching previous literature" - since we are now discussing the proper way to use the scientific method.

So Patrick, please do not feel that I have put that imposition on you to do "my" testing. Please do continue to work on your own hypotheses.

For everyone else, thanks your your feedback and input on the subject. I guess the bottom line then is that other than Jay's observations about his developer that uses a low buffer, high pH alkali, it seems no one else has purposely tried this approach.

And since I have yet to make my quotation contribution to this thread, I would like to submit Arthur C. Clarke's Third Law - "Any sufficiently advanced technology is indistinguishable from magic." To Clarke's astute observation, I would like to submit my own corollary, "Any sufficiently different science or technology from one's own field of study will be indistiguishable from magic."

I often feel we are all subject to this corollary as we try to fiddle with our photochemicals.

Happy testing!
 

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Patrick, I have indeed tested the effects of dilution and buffer capacity in practice and mathematically and find good agreement. That is why I think that Kirk has made a vaild point.

I have also tested the swell component and the diffusion component and find that they agree well with the math models.

It is interesting to not that you did not finish your chemistry education, but rather went into aeronautical engineering. Now you suddenly find that you are an authority on photographic chemical matters. My education is not in aeronautical engineering, but rather in chemistry and photographic chemistry.

I would not think of debating an issue in aeronautical engineering with you. Instead, were I interested in that field, I would be avidly listening to what you might be trying to tell me in your chosen field of expertise. Shouldn't we be approaching this somehow with the idea that what I say might have a grain of truth and that I have tested these statements? Shouldn't it be sufficient that models exist and publications exist verifying these models?

Kirk has opened up a nice field for investigation, namely the effects of buffer exhaustion on image structure in stand, semi-stand and generally dilute developers. I think it merits consideration, and I gave my reasoning above.

Instead of considering it, it seems that you prefer to treat the idea with some degree of disapproval or dismiss it outright.

Of course you are right that science does not have the answer to everything and that some models are only approximations. The people in this thread that say 'photography is art' are right as well. It is not just science. But even the best artist is a closet scientist in a way, making empirical changes to get better results. I have tried to place this information on a more formalized basis rather than on the level of the 19th century 'snake oil' salesman. Even they found usable cures though, but it took medical science to turn that from 'snake oil' into usable stable drugs.

I am suggesting that insted of trial and error, we find out what is going on in some of these 'exotic' processes and developers and reduce it to some sort of coherent picture so that a person can come close to good results without wasting a lot of time, effort and money. Kirk's thinking on this matter may be a move in that direction. I don't know, but dismissing the entire discussion with your quotations debases the entire scientific portion of this discussion.

After all, isn't the science of photography part of what APUG is supposed to support?

PE
 

gainer

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Hey there! I didn't dismiss anything. You are the only person I have ever met who accused me of rejecting new ideas. Most have thought I was crazy for introducing them. I HAVE tested the idea of alkali exhaustion and it works. It is capable of giving true compensating development with certain ascorbate developers.

Trial and error, as it seems you have forgotten, is the scientific method. Every time you apply a theoretical relationship to new ground, you must test the new application. If you think I just go into the testing phase without expecting a particular result, you don't know mw at all, nor do you know anything I have written. The trial is of some hypothesis. The science is gained when the expected result is either as predicted or not. The rejection of the result implies that there was an error in the hypothesis. The prediction of the expected result does not prove the theory, but only shows that it cannot be rejected on the available evidence.

One of the things we studied at engineering school in my days was everything. One of our professors told us engineers can do anything. I never claimed to be an expert at chemistry. My idea of an expert is one who knows more and more about less and less until he knows all there is to know about nothing. I did not start out to be a chemist, but a chemical engineer. My chosen field of expertise did not wind up being my final one at NASA. That was Human Factors, sometimes called Engineering Psychology. I used my photographic and optics knowledge quite a bit, including designing a star projector for use in simulations.

The first three years of the Chemical Engineering curriculum included courses in surveying, mechanics (as in Newtonian Mechanics), strength of materials, quantitative and qualitative chemical analysis, and physical and organic chemistry, among other things.
 

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For more information on this matter, please see "The Film Developing Cookbook", by Anchell and Troop, page 67. There is a quote from Crawley that applies to Kirk's original hypothesis regarding exhaustion effects.

As for education, I'm sharing information from Dr. Mees, Dr. James, Dr. Liang and Dr. Willis among others. Add to that, Dr. Crawley and Anchell and Troop. That was the only meaning behind my comment.

As for dismissive comments, I'm not the one that began posting the quotes above that were intended to cast aspersions on anyones statements. What else did you mean then by posting them?

PE
 

gainer

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Kirk Keyes said:
Patrick - I in no way was asking you (or anyone else here) to test my hypothesis when I posted this thread. I was merely looking to see if someone else hade already made a similar observation. I think that this is similar to what is often referred to as "researching previous literature" - since we are now discussing the proper way to use the scientific method.

So Patrick, please do not feel that I have put that imposition on you to do "my" testing. Please do continue to work on your own hypotheses.

.

Happy testing!
I know, Kirk. I was not aiming that comment at you. I have told Sandy King what I have been testing. Basically, the hypothesis is that an ascorbate developer with minimum alkali will make a good stand developer whether or not the concentration of developing agents is such as to cause local starvation because the products of ascorbate developers are more acidic than those of the hydroxy phenols. To test the hypothesis, I used an ascorbate-amidol developer in a glycol stock solution in order to make it easy to change athe amount of alkali separately. Call this A. TEA is the alkali I chose. The working dilution of A was kept constant at 1 part A to 50 parts water. The minimum amount of TEA was found by titrating with a pH indicator from a swimming pool test kit to get the first tint of pink. This solution, in 40 minutes standing at 75 F gave about normal contrast as determined by density measurements of images of a step density wedge. The solution was, per liter of working solution, 20 ml A and 3 ml TEA.

A solution of 20 ml/liter A and 4 ml/l TEA gave higher overall contrast at 20 minutes standing at 75 F. It crossed over the other curve bteween 3.5 and 4 log exposure units above the 0.1 level that most now use as the speed point, being lower on the shadow side and higher on the highlight side.

The net result is that by reducing only the amount of TEA, we have obtained a desirable increase in what we like to call compensation. I can show this curve in a small JPG file. I have also tested pictorially, but in order to see the resolution, sharpness and lack of graininess you would either have to do it yourself or see a photographic print.
 
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Kirk Keyes

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gainer said:
Trial and error, as it seems you have forgotten, is the scientific method.

Side note to the discussion for those that are not familiar with the actual process that is konwn as the scientific method - there is much more to it than "trial and error". In fact that really doesn't fit in to the scientific method. A better discription of the scientific method is as follows, there are 4 steps:

1. Observation and description of a phenomenon or group of phenomena.

2. Formulation of an hypothesis to explain the phenomena. In chemistry, the hypothesis often takes the form of a causal mechanism or a mathematical relation.

3. Use of the hypothesis to predict the existence of the phenomena, or to predict quantitatively the results of new observations.

4. Performance of experimental tests of the predictions by several independent experimenters and properly performed experiments.

(The above was mostly taken from the excellent web page http://teacher.nsrl.rochester.edu/phy_labs/AppendixE/AppendixE.html )

I completed Step 1 sometime before I started this thread. I originally mentioned pH, but then PE pointed out that buffer action combined with the solution pH was really probably a better hypothesis. So now we are up to step 3. As I have no experience with stand development, I suggest that anyone who wishes can try to make some observations (Step 3) and see if the hypothesis holds up. Then we can move to Step 4.

"Trial and error" kind of trivializes the entire process, as well as puts an imprecise spin on the actual process.

I apologize to those that find these sorts of posts uninteresting.
 
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