Experiences with Vitamin C developers please

john_s

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When PMK was being popularized Michael's point (1) was mentioned, and since then many of us have found PMK to be stable and quite long-lasting.
 

Gerald C Koch

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john_s said:
When PMK was being popularized Michael's point (1) was mentioned, and since then many of us have found PMK to be stable and quite long-lasting.
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Just passing on what I have read several times about pyrogallol.

The other part of my post seems to have been overlooked. Jay deFehr did not recommend any greater dilution than 1+100 except for stand and semi-stand methods. The OP was using a dilution of 1+200 with fairly constant agitation. With constant agitation the amount of oxygen in the water is constantly being replaced.
 

sfaber17

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Rudeofus said:
There isn't that much Oxygen dissolved in water at room temperature. Also, the fact remains that swmcl didn't see much improvement when he added Salicylic Acid and Ascorbic Acid. The effect of AA on development in 510 Pyro must be minor IMHO.
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I calculate that the dissolved oxygen then would use up 0.1g of AA, or 20% or more if the oxygen is being replaced. Your points make a lot of sense, and I tend to believe the AA is reversing the oxidation products of the Pyro. I put a bit of iodine in the developer to get a brown oxidation product and then reversed it somewhat with some more AA. Not sure if it is designed to use up all the AA. Note that oxidation by film and chlorine would generate H+ but not 02. From Gainer's article, one roll of film would oxidize .05g of AA or .024g of Pyro, so with 300ml at 1:100 you couldn't do more than 3 rolls, or 2 counting oxygen. I found an article where Jay describes developing 510-Pyro. There he mentions using 99% TEA from chemistry store. Another post I saw from Sandy King said he found .1g AA/liter made the pyrocat series more active. Jay started using the .1g/l AA and enough Pyro to get stain but not too much general stain. Then reduced the Phenidone to a level where it started to make a difference, and then increased the AA to a level where it would not inhibit the desired stain. He did do H-D curves and went for good constrast. He found the higher level of AA helped reduce grain and help with rotary processing.
 
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swmcl

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Sorry for the delayed response ... a little 3500km journey to pick up an enlarger ...

Can I refer back to #92 by Rudeofus and say that I made a concoction with many of the ingredients of the original but in glycol. I then processed a sheet using a 1:100 solution of sodium carbonate. (200g in 1 litre).

The result was very unusual for me.

The sheet is a very distinct green like the slime in a pond - general stain. The CI isn't terribly good at around 0.4 IIRC. The working solution was the colour of Guinness when it was poured out and the first water wash was a scotch colour. I did a second wash to get a clearish result !

So that is a demonstration of higher pH as it started at just under 11 IIRC. To me a good demonstration of Pyrogallol needing a higher pH. I'm thinking of reducing the carbonate solution to a point where the pH is around 10.2 or so.

I felt a bit like Young Einstein I do admit. All it needed was some CO2 gas coming off the drum and a good amount of bubbles !!

Now that I am back, I do intend to try something like it again. I'm thinking that the glycol is a better solvent in that if there is an amount of water it won't start reacting so much in the stock solution.

Do remember my densitometer readings from my first use of a newly mixed 510 are very different from the stock solution today. I and a friend decided on 1:200 based on our and others' experiences. There are others using 510 at a 1:400 dilution in stand development. My friend used 510 at 1:100 and ridiculous contrast issues.

Ahh we digress.
 

Rudeofus

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You get stain both from Pyro oxidized by aerial Oxygen, and from Pyro oxidized by developable silver halide. Background stain indicates that aerial Oxygen was the cause, and there are two ways to decrease its effect: lower pH, or add a scavenger/reducer for the oxidized Pyro. As it just so happens, Ascorbic Acid does both, so your next course of action would be gradually adding AA until background stain is minimized. At the same time you should see an increase in contrast.

swmcl said:
So that is a demonstration of higher pH as it started at just under 11 IIRC. To me a good demonstration of Pyrogallol needing a higher pH. I'm thinking of reducing the carbonate solution to a point where the pH is around 10.2 or so.
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Since the molecular weight of TEA is about 3/2 of that of water, you should get results more comparable to 510 Pyro with about 6 g/l anhydrous Sodium Carbonate (assuming you use 510 Pyro in 1:100 dilution). If pH is still too high then, and you have already added all the AA you needed to remove background stain, lower pH with Acetic Acid or Citric Acid.
 

mrred

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But why use 510-Pyro at all if you feel the need to do something else with it. It was designed to be a 'simple' formula. There are probably better ones out there that would get closer to what you need.

I would suggest trying the hypercat recipe, as it uses carbonate alkili and AA to deal with the scavenging. You are probably on the same path as Jay when he thought of it.
 

Rudeofus

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Peter: the greatest argument for rescuing 510 Pyro is the three liters of concentrate he made. That's some investment, and I'm positive that a pinch of Carbonate and another pinch of Ascorbic Acid is all that's needed to make that happen.
 

mrred

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Valid point. With the addition of some AA might compensate tec grade tea (%85) as well. Might try a small batch of that to see. next time I make an order I will have to see if I can get some pyrogallol.
 

Bruce Osgood

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There was a very popular contributor to APUG named Patrick Gainer. I believe he has passed away and that is a loss in itself. His life at the time seemed to revolve around Vitamin C in its' various formulations as a developer.

There is an article with his many recipes at Unblinking Eye: " http://unblinkingeye.com/Articles/VitC/vitc.html "

You may find this of interest if you haven't already been through it. Or, maybe not.
 
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swmcl

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Hi Bruce,

I've read a number of the Patrick Gainer articles and posts over the past 6 months. He was a very helpful and humble servant of the cause for sure. A really nice guy.

Fellas, I've got a house invader at present (a mother-in-law) so my attentions are focused on family issues for another week or so but I'll seek to try a sheet with a lowered carbonate content and thereby a lower pH. I initially used a 1:100 dilution from the 200g per litre concentrate just because that was what the Pyrocat-HD uses I think it was.

This would be fun if I, 1: knew what I was doing in terms of chemical reactions and 2: had a great interest in the chemistry of photography. All I want is a staining / tanning developer that has a wide dilution variations which might allow a good variation in development curves, strength to develop to very strong densities if I need it to, is reliable over time and is long lasting. The discussion of accutance effects etc is something for small format photographers to my mind. I think I might try a double-strength Pyrocat-HD along the way.

I did a sheet of Rodinal at 1:50 20C for 8 mins and got a gradient of 0.66 ... just to put things in perspective !! Perhaps the idea would be to stick to Pyrocat-HD for low gradient images and go the Rodinal when I want to spice things up ! The task will be to calm the Rodinal down in actual fact (Remembering that I can't do stand development with 4x5 and 5x7 sheets).

Cheers all,

Steve
 
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swmcl

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Can I add that two of us have tried the freshly mixed 510 at 1:100. It was very contrasty. It seemed there were no midtones.

With three developing agents in the mix I expect something pretty vigorous. When the three agents are separated from the alkali (or 'accelerator') then it might be possible to dilute the alkali first to give an acceptable pH and then add an amount of developer stock to more gently do its work. That's what I hope anyway.

I am not sure of the alkali and developing agents all in together anymore. To get an acceptable pH I am adding a certain amount of developing agents with the result being a real bubbling cauldron as it were.

I don't understand at all how the stand dev works at even higher dilutions. What would the pH be at 1:400 ? Surely the pyrogallol wouldn't be doing much !

Anyways ... you can probably tell I am a person who like to hear of gradients and pH levels etc. The simple exclamation of, "Oh I got a wonderful result !" simply doesn't cut it I'm afraid.

Again for today, Cheers !
 

Gerald C Koch

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If 510-pyro at 1:100 is creating too much contrast there is no reason why some of the TEA cannot be replaced with glycol thereby reducing the pH of the developer. When using very dilute solutions there is always the possibility of distorted tonal range and non-uniform development.
 

MattKing

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I could be wrong, but I don't beleve Patrick Gainer has passed away. As I understand it though, he is in ill health and is no longer working with developers.
 

Photo Engineer

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One thread common to many home brew developers is the variation in activity and results from person to person, and the great trouble in setting up a satisfactory workflow and chemical source.

I'm afraid that you are going to continue to see this sort of problem. We saw it at EK, and damped it out by selecting only the very best chemistry and by using stable chemical mixes. You get the same result every time. With a home brew, you do not.

PE
 

rbultman

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Does "home brew" apply to home mixed from raw ingredients using a published formula, a home designed developer, or both? Would you expect something like 510-Pyro to have "troubling" variation batch-to-batch when mixed from ingredients as compared to a pre-mixed developer like XTOL? I've been curious to try something like 510-Pyro or Thornton's 2 bath, but I don't want to sign up for a bunch of testing with every batch.

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mrred

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rbultman: PE raises some valid points, but I think you are being a bit dramatic. I don't know why you are not willing to do a few tests along the way....they are not SATs. Pretty easy stuff.

I buy metol 1 lb at a time. My AA comes in a 5 lb jug (factory near by). I try to be as consistent as I can. From time to time things shift a little, but it's easy to compensate. It is not the end of the world.

But if you are a "published specs" junkie, you should not DYI. But you could live on the edge once in a while. Making mistakes makes you better.
 

Bruce Osgood

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MattKing said:
I could be wrong, but I don't beleve Patrick Gainer has passed away. As I understand it though, he is in ill health and is no longer working with developers.
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I hope you are right. Thanks for the information. At least there is hope that ill health can be remedied.
 

Photo Engineer

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I am referring to both types of formulas, published formula and home designed. The home brew phrase is in reference to being mixed from scratch at home.

I have had cases of buying a chemical from "A" and then from "B" and getting entirely different results in my own formula. Now this happened more than one time and happened at home here and at EK taking from 2 10KG bottles we bought. So I can allude to practical experience with this and with mixing up chemistry that went into production. They got different results in production when buying (or making) in tank car lots and thus they tweaked the formula.

So, when I told them 100 g/l, they said sorry 115 g/l gets the result you told us. The sources were different.

Now, to continue, about 10 - 20 years ago, hypo was shipped across country by tank car lots. Today it is shipped in 55 # drums. By the same token, the method of manufacture has changed to suit this. The same paradigm shift has taken place with Metol and HQ. At one time, Kodak had an entire plant in TX that made nothing but HQ, 24/7 and today it is made in tiny (compared to this plant) scale at several chemical companies. And so, the quality differs depending on who you order it from.

As you go from these chemicals to the even rarer photochemicals, then you get even more chance of variation. Typically, an organic chemical is never 100% or even 95% pure. They have to be recrystallized or somehow purified of the side products and starting materials. So, look up the chemical you want on Wikipedia and it will typically tell you the purity available and even the yield when made.

I've seen yields of some reducing agents (such as developers), that give yields of 50% or less. That means that in the first cut the chemist has stuff that is only 50% pure, but another chemist might get 70% from the same reaction. Now, the companies here have to purify these two samples to workable concentrations and this is expensive, and so one sample ends up at 90% and the other at 98% for the same cost.

I hope you follow what I am saying. I've had this same gotcha. And so that is why any Kodak products such as good old D76, or HC110 or any similar Ilford product is so reliable. But it can bring in to question the reliability of scratch mixes or home brews!

So far, I have been ok with standard mixes, but I see more problems with outliers such as VitC and staining developers.

Thats it.

PE
 

rbultman

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Thanks all for the responses regarding using bulk chemicals. I have had good success with packaged developers (XTOL, Rodinal/R09, ID11) and not great success with one published formula. My free time is nearly non-existent so any time I spend testing takes away from time spent shooting, processing, or printing.
 

Gerald C Koch

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When I was in graduate school I was sent to the stock room to get a 1 pound bottle of analyzed reagent grade silver nitrate. Printed on each bottle's label was a guaranteed analysis of the chemical inside. When the sealed bottle was opened there was a very large, dead moth inside. So much for quality control.
 
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JW PHOTO

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Gerald, I know exactly what you mean. I once bought a bottle of expensive Mexican Tequila and there was a worm in the bottom of the bottle. Didn't seem to alter the taste at all, but the worm was chewy.
 

mrred

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it's a shame when you order a worm and get all that liquid....,

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swmcl

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Unfortunately, PE is dead right. I have spent a whole bunch of time trying to stabilise my process around a product that for all my good intentions and purchasing from very reputable places (most of the time ...!) I think what I'm seeing is a variation due to chemical impurity to some extent. I've learnt a bit more though especially thanks to you who have been involved with this thread.
 
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