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#1
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Rodinal and Patrick Gainer
Gents & Patrick:
I think I've assembled the ingredients, but I'd like to form a rudimentary understanding of the differences between Patrick's formula (below) and the one I dug out of Anchell which follows. I must admit that I got the hydrochloride from the Photographer's Formulary before I read the fine print. Can anyone weigh in on this? Gainer Rodinal: 700 ml water. Add 150 grams sodium sulfite and 14 grams of sodium hydroxide. Red Devil lye will do. When the solids are dissolved, bring the volume up to 1 liter with water, put the solution in a 1 liter storage container and add 40 grams of p-aminophenol (not the hydrochloride), shake well and serve. Use it as Rodinal. There will be some precipitate. This is the "few remaining crystals" of the standard recipe and is the protection against aerial oxidation. Of course, you don't believe me, but try it anyway. ie 700 ml water 150g sodium sulfite 14g sodium hydroxide 40g p-aminophenol Here's the Anchell version 750ml water 100g p-aminophenol hydrochloride 300g potassium metabisulfite 200g sodium hydroxide (actual amount determined while mixing) -Lew |
#2
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Rodinal and Patrick Gainer
lew wrote:
Gents & Patrick: I think I've assembled the ingredients, but I'd like to form a rudimentary understanding of the differences between Patrick's formula (below) and the one I dug out of Anchell which follows. I must admit that I got the hydrochloride from the Photographer's Formulary before I read the fine print. Can anyone weigh in on this? The primary difference is the choice of p-aminophenol base vs. p-aminophenol*HCl. Usually the aminophenols and similar developing agents are prepared as the acid salt... for instance, p-aminophenol hdyrochloride, Metol, etc. The acid salts are very stable in powder form compared to the free bases, and the acid salts are soluble in water. The Anchell formula I have is quite different from that which you posted. It is: ---------- Rodinal-type Developer This formula is very similar to Agfa Rodinal. Rodinal is the oldest proprietary formula in use today, the original formula dating back to the 1880s. It is considered by some to be the finest all around film developer, even for modern T-grain films. Solution A Water (125°F/52°C) 750.0 ml P-Aminophenol hydrochloride 100.0 grams Potassium metabisulfite 300.0 grams Cold water to make 1 .0 liter Solution B Sodium hydroxide 50.0 grams Cold water 100.0 ml CAUTION: When the 50% solution of sodium hydroxide is being made up, heat is generated. The solution must be cooled before adding to the developer. Allow Solution A to cool. A precipitate of p-Aminophenol hydrochloride will form. Slowly add, drop by drop, Solution B to Solution A until the precipitate almost disappears. Do not dissolve all of the visible precipitate! Leave a few crystals undissolved (as few as two or three). --------- Actually, the precipitate that is formed is the free base, which is ionized by base and goes back into solution. This is another preparation for Rodinal which I pulled from an old forgotten reference: ----------- Rodinal Preparation: Boil 250 ml water, cool to 125F, and add a few crystals of potassium metabisulfite, followed by 20 g of para-aminophenol hydrochloride. After the para-aminophenol-HCl dissolves, add 60 g potassium metabisulfite, and stir until dissolved. Then add a solution of 40% (w/v) sodium hydroxide which thickens the solution as the para-aminophenol base precipitates, and then goes back into solution as the phenolate anion as more sodium hydroxide is added. Stop the addition of sodium hydroxide while there is still a small amount of precipitate left, and add water to make 400 ml. Set aside to cool, and place in a glass bottle. A small amount may come out of solution, but the addition of sodium hydroxide will dissolve it. If there is no precipitate, excess sodium hydroxide may be present, and a saturated potassium bisulfite solution may be used to neutralize it. (The amount of 40% sodium hydroxide required is approx 70 ml.) A small amount of precipitate is desired, since this occurs at the lowest pH at which the para-aminophenol is in solution. The addition of more base results in a higher pH at which the solution oxidizes more rapidly. ---------------- Again, a small amount of precipitate is left in the solution, In a way, the solubility of the base in the alkaline solution is being used as a pH indicator to insure that an excessive amount of hydroxide isn't present, that would give a very high pH and short shelf life. When I used commercial preparations of Rodinal I transfered them to a glass bottle and titrated them with bisulfite until the a few crystals precipitate formed. I started the practice after Agfa changed the their preparation (more basic - no crystals). |
#3
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Rodinal and Patrick Gainer
Mine's from the Cookbook, p.162. Apart from the mixing instructions, they're
identical. "Michael Gudzinowicz" wrote in message news:bImqf.5240$Ap1.1899@trndny06... lew wrote: Gents & Patrick: I think I've assembled the ingredients, but I'd like to form a rudimentary understanding of the differences between Patrick's formula (below) and the one I dug out of Anchell which follows. I must admit that I got the hydrochloride from the Photographer's Formulary before I read the fine print. Can anyone weigh in on this? The primary difference is the choice of p-aminophenol base vs. p-aminophenol*HCl. Usually the aminophenols and similar developing agents are prepared as the acid salt... for instance, p-aminophenol hdyrochloride, Metol, etc. The acid salts are very stable in powder form compared to the free bases, and the acid salts are soluble in water. The Anchell formula I have is quite different from that which you posted. It is: ---------- Rodinal-type Developer This formula is very similar to Agfa Rodinal. Rodinal is the oldest proprietary formula in use today, the original formula dating back to the 1880s. It is considered by some to be the finest all around film developer, even for modern T-grain films. Solution A Water (125°F/52°C) 750.0 ml P-Aminophenol hydrochloride 100.0 grams Potassium metabisulfite 300.0 grams Cold water to make 1 .0 liter Solution B Sodium hydroxide 50.0 grams Cold water 100.0 ml CAUTION: When the 50% solution of sodium hydroxide is being made up, heat is generated. The solution must be cooled before adding to the developer. Allow Solution A to cool. A precipitate of p-Aminophenol hydrochloride will form. Slowly add, drop by drop, Solution B to Solution A until the precipitate almost disappears. Do not dissolve all of the visible precipitate! Leave a few crystals undissolved (as few as two or three). --------- Actually, the precipitate that is formed is the free base, which is ionized by base and goes back into solution. This is another preparation for Rodinal which I pulled from an old forgotten reference: ----------- Rodinal Preparation: Boil 250 ml water, cool to 125F, and add a few crystals of potassium metabisulfite, followed by 20 g of para-aminophenol hydrochloride. After the para-aminophenol-HCl dissolves, add 60 g potassium metabisulfite, and stir until dissolved. Then add a solution of 40% (w/v) sodium hydroxide which thickens the solution as the para-aminophenol base precipitates, and then goes back into solution as the phenolate anion as more sodium hydroxide is added. Stop the addition of sodium hydroxide while there is still a small amount of precipitate left, and add water to make 400 ml. Set aside to cool, and place in a glass bottle. A small amount may come out of solution, but the addition of sodium hydroxide will dissolve it. If there is no precipitate, excess sodium hydroxide may be present, and a saturated potassium bisulfite solution may be used to neutralize it. (The amount of 40% sodium hydroxide required is approx 70 ml.) A small amount of precipitate is desired, since this occurs at the lowest pH at which the para-aminophenol is in solution. The addition of more base results in a higher pH at which the solution oxidizes more rapidly. ---------------- Again, a small amount of precipitate is left in the solution, In a way, the solubility of the base in the alkaline solution is being used as a pH indicator to insure that an excessive amount of hydroxide isn't present, that would give a very high pH and short shelf life. When I used commercial preparations of Rodinal I transfered them to a glass bottle and titrated them with bisulfite until the a few crystals precipitate formed. I started the practice after Agfa changed the their preparation (more basic - no crystals). |
#4
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Rodinal and Patrick Gainer
lew wrote:
Mine's from the Cookbook, p.162. Apart from the mixing instructions, they're identical. "Michael Gudzinowicz" wrote in message news:bImqf.5240$Ap1.1899@trndny06... lew wrote: Gents & Patrick: I think I've assembled the ingredients, but I'd like to form a rudimentary understanding of the differences between Patrick's formula (below) and the one I dug out of Anchell which follows. I must admit that I got the hydrochloride from the Photographer's Formulary before I read the fine print. Can anyone weigh in on this? The primary difference is the choice of p-aminophenol base vs. p-aminophenol*HCl. Usually the aminophenols and similar developing agents are prepared as the acid salt... for instance, p-aminophenol hdyrochloride, Metol, etc. The acid salts are very stable in powder form compared to the free bases, and the acid salts are soluble in water. The Anchell formula I have is quite different from that which you posted. It is: ---------- Rodinal-type Developer This formula is very similar to Agfa Rodinal. Rodinal is the oldest proprietary formula in use today, the original formula dating back to the 1880s. It is considered by some to be the finest all around film developer, even for modern T-grain films. Solution A Water (125°F/52°C) 750.0 ml P-Aminophenol hydrochloride 100.0 grams Potassium metabisulfite 300.0 grams Cold water to make 1 .0 liter Solution B Sodium hydroxide 50.0 grams Cold water 100.0 ml CAUTION: When the 50% solution of sodium hydroxide is being made up, heat is generated. The solution must be cooled before adding to the developer. Allow Solution A to cool. A precipitate of p-Aminophenol hydrochloride will form. Slowly add, drop by drop, Solution B to Solution A until the precipitate almost disappears. Do not dissolve all of the visible precipitate! Leave a few crystals undissolved (as few as two or three). --------- Actually, the precipitate that is formed is the free base, which is ionized by base and goes back into solution. This is another preparation for Rodinal which I pulled from an old forgotten reference: ----------- Rodinal Preparation: Boil 250 ml water, cool to 125F, and add a few crystals of potassium metabisulfite, followed by 20 g of para-aminophenol hydrochloride. After the para-aminophenol-HCl dissolves, add 60 g potassium metabisulfite, and stir until dissolved. Then add a solution of 40% (w/v) sodium hydroxide which thickens the solution as the para-aminophenol base precipitates, and then goes back into solution as the phenolate anion as more sodium hydroxide is added. Stop the addition of sodium hydroxide while there is still a small amount of precipitate left, and add water to make 400 ml. Set aside to cool, and place in a glass bottle. A small amount may come out of solution, but the addition of sodium hydroxide will dissolve it. If there is no precipitate, excess sodium hydroxide may be present, and a saturated potassium bisulfite solution may be used to neutralize it. (The amount of 40% sodium hydroxide required is approx 70 ml.) A small amount of precipitate is desired, since this occurs at the lowest pH at which the para-aminophenol is in solution. The addition of more base results in a higher pH at which the solution oxidizes more rapidly. ---------------- Again, a small amount of precipitate is left in the solution, In a way, the solubility of the base in the alkaline solution is being used as a pH indicator to insure that an excessive amount of hydroxide isn't present, that would give a very high pH and short shelf life. When I used commercial preparations of Rodinal I transfered them to a glass bottle and titrated them with bisulfite until the a few crystals precipitate formed. I started the practice after Agfa changed the their preparation (more basic - no crystals). My "theory" on the reason for leaving some undissolved crystals is that they extend the shelf life by a sort of regeneration. Aerial oxidation of a molecule of p-aminophenol in the presence of sulfite produces a monosulfonate and a molecule of the hydroxide, potassium or sodium depending on which you used. If there is a molecule of p-aminophenol lying around in the bottom of the container, it will be converted to the sodium (or potassium) aminophenolate which is the active agent in Rodinal. and will replace the oxidized molecule. Actually, the main reason for the undissolved crystals may be to get rid of all the oxygen that was dissolved in the water when you mixed the solutions. At any rate, the excess p-aminophenol is precipitated and will not affect the activity of the developer, so there is no need to be finicky about how many crystals one leaves undissolved. A similar developer can be made using Metol instead of p-aminophenol. You will have to add enough hydroxide to change the hydrosulfate (sulfuric acid) to sodium or potassium sulfate and some more to form the sodium or potassium salt of the 4(methyl-amino)phenol. I leave quite a bit undissolved, and it seems to be lasting qhite well. It gives a little more shadow speed than Rodinal for the same contrast. 63 grams of Metol have about the same number of molecules as 40 grams of the p-aminophenol, so you will need enough NaOH to neutralize 23 grams of sulfuric acid in addition to the amount used for 40 grams of the p-aminophenol base. |
#5
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Rodinal and Patrick Gainer
PATRICK GAINER wrote:
lew wrote: Mine's from the Cookbook, p.162. Apart from the mixing instructions, they're identical. "Michael Gudzinowicz" wrote in message news:bImqf.5240$Ap1.1899@trndny06... lew wrote: Gents & Patrick: I think I've assembled the ingredients, but I'd like to form a rudimentary understanding of the differences between Patrick's formula (below) and the one I dug out of Anchell which follows. I must admit that I got the hydrochloride from the Photographer's Formulary before I read the fine print. Can anyone weigh in on this? The primary difference is the choice of p-aminophenol base vs. p-aminophenol*HCl. Usually the aminophenols and similar developing agents are prepared as the acid salt... for instance, p-aminophenol hdyrochloride, Metol, etc. The acid salts are very stable in powder form compared to the free bases, and the acid salts are soluble in water. The Anchell formula I have is quite different from that which you posted. It is: ---------- Rodinal-type Developer This formula is very similar to Agfa Rodinal. Rodinal is the oldest proprietary formula in use today, the original formula dating back to the 1880s. It is considered by some to be the finest all around film developer, even for modern T-grain films. Solution A Water (125°F/52°C) 750.0 ml P-Aminophenol hydrochloride 100.0 grams Potassium metabisulfite 300.0 grams Cold water to make 1 .0 liter Solution B Sodium hydroxide 50.0 grams Cold water 100.0 ml CAUTION: When the 50% solution of sodium hydroxide is being made up, heat is generated. The solution must be cooled before adding to the developer. Allow Solution A to cool. A precipitate of p-Aminophenol hydrochloride will form. Slowly add, drop by drop, Solution B to Solution A until the precipitate almost disappears. Do not dissolve all of the visible precipitate! Leave a few crystals undissolved (as few as two or three). --------- Actually, the precipitate that is formed is the free base, which is ionized by base and goes back into solution. This is another preparation for Rodinal which I pulled from an old forgotten reference: ----------- Rodinal Preparation: Boil 250 ml water, cool to 125F, and add a few crystals of potassium metabisulfite, followed by 20 g of para-aminophenol hydrochloride. After the para-aminophenol-HCl dissolves, add 60 g potassium metabisulfite, and stir until dissolved. Then add a solution of 40% (w/v) sodium hydroxide which thickens the solution as the para-aminophenol base precipitates, and then goes back into solution as the phenolate anion as more sodium hydroxide is added. Stop the addition of sodium hydroxide while there is still a small amount of precipitate left, and add water to make 400 ml. Set aside to cool, and place in a glass bottle. A small amount may come out of solution, but the addition of sodium hydroxide will dissolve it. If there is no precipitate, excess sodium hydroxide may be present, and a saturated potassium bisulfite solution may be used to neutralize it. (The amount of 40% sodium hydroxide required is approx 70 ml.) A small amount of precipitate is desired, since this occurs at the lowest pH at which the para-aminophenol is in solution. The addition of more base results in a higher pH at which the solution oxidizes more rapidly. ---------------- Again, a small amount of precipitate is left in the solution, In a way, the solubility of the base in the alkaline solution is being used as a pH indicator to insure that an excessive amount of hydroxide isn't present, that would give a very high pH and short shelf life. When I used commercial preparations of Rodinal I transfered them to a glass bottle and titrated them with bisulfite until the a few crystals precipitate formed. I started the practice after Agfa changed the their preparation (more basic - no crystals). My "theory" on the reason for leaving some undissolved crystals is that they extend the shelf life by a sort of regeneration. Aerial oxidation of a molecule of p-aminophenol in the presence of sulfite produces a monosulfonate and a molecule of the hydroxide, potassium or sodium depending on which you used. If there is a molecule of p-aminophenol lying around in the bottom of the container, it will be converted to the sodium (or potassium) aminophenolate which is the active agent in Rodinal. and will replace the oxidized molecule. Actually, the main reason for the undissolved crystals may be to get rid of all the oxygen that was dissolved in the water when you mixed the solutions. At any rate, the excess p-aminophenol is precipitated and will not affect the activity of the developer, so there is no need to be finicky about how many crystals one leaves undissolved. A similar developer can be made using Metol instead of p-aminophenol. You will have to add enough hydroxide to change the hydrosulfate (sulfuric acid) to sodium or potassium sulfate and some more to form the sodium or potassium salt of the 4(methyl-amino)phenol. I leave quite a bit undissolved, and it seems to be lasting qhite well. It gives a little more shadow speed than Rodinal for the same contrast. 63 grams of Metol have about the same number of molecules as 40 grams of the p-aminophenol, so you will need enough NaOH to neutralize 23 grams of sulfuric acid in addition to the amount used for 40 grams of the p-aminophenol base. I goofed a little. There are not quite 23 grams of sulfuric acid in 63 grams of Metol. I forgot to account for the methyl part. For 63 grams of Metol, I use 28 grams of NaOH and 150 grams Na2SO3 in a liter of water. Some precipitate remains. It should be about 3 grams, but it looks like more because the precipitatee is fluffy. |
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