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Water prepare Pyrocat-HD

Philippe Berger

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Hi
For the developer Pyrocat_HD 1: 1: 100
To add, must -there of distilled water or demineralized water?
What should the PH of the water
Likewise for the Pre-soak, it takes alkaline water, can you tell me the pH of this alkaline water.
Can we prepare it with baking soda. It takes how much baking soda to a quart of water or other prepare

Thank
 

gzinsel

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to minimize contaminants in tap water, use distilled water. You can skip pre-soak, if you want to. do not add alkali to pre-soak. just use plain distilled water. when you have drained presoak, pour in developer. Your developer should be made with distilled water, for best results. Use distilled water to make part A and Part B. (*Add 1 part A to 1 part B, add both to 100 parts water)( multiple by x to get to total volume) . if you use distilled water, you do not need to worry about measuring or monitoring the PH. Its all in part B.
FYI- BAKING SODA IS NOT RECOMMENDED FOR ANY PYRO_CAT HD FORMULA.


PYROCAT HD
Stock Solution A
Distilled Water (125°F) 750 ml
Sodium metabisulfite 10 g
Pyrocatechin 50 g
Phenidone 2g
Potassium Bromide 1g
Water to make (68°F) 1 liter

Stock Solution B
Distilled Water (68°F) 750 ml
Potassium Carbonate 750 g
Water to make (68°F) 1 liter

To make a standard working solution mix 1 part A with 1 part B with 100 parts water for general photography film.


1. Pre-soak for five minutes. The pre-soak is optional with tray and tank development (except with minimal and stand development), but it is absolutely essential with rotary processing. 

2. Development for the required time.
3. Plain water STOP BATH If the stop bath is too strong it will reduce image stain.
4. The use of an alkaline fixer is recommended. Kodak and Ilford Rapid-Fix work fine, as does Formulary TF-4. I use the TF-3 formula described in Anchell and Troop’s The Film Developing Cookbook. 

5. If NO ACID is used omit Hypo Clear, Otherwise use- One minute in a hypo-clearing agent. I use a 1% solution of sodium sulfite. 
Do NOT add Bisulfite to Hypo Clear.
6. 6. Wash in running water for 15 minutes.
DEVELOPMENT OF FILM IN TANKS

Pyrocat-HD can be used to develop 35mm, roll film, and sheet film in tanks following conventional procedures with no special precautions.
Normal Agitation — Normal agitation for tank development is considered to be continuous agitation for the first 60 seconds of development, then agitation for 5-10 seconds every 30-60 seconds thereafter. With this pattern of agitation Pyrocat-HD can be used with no modification to your normal development procedures for conventional developers.

Minimal Agitation — Minimal agitation consists of continuous agitation for the first 60 seconds of development, followed by 10 seconds of agitation every third minute. With this method a pre-soak of five minutes is strongly recommended to avoid the possible formation of bubbles on the emulsion. Minimal agitation has three desirable results: 1) it gives great apparent sharpness through the formation of maximum adjacency effects, 2) it provides a compensating effect, and 3) it provides increased emulsion speed. With minimal agitation you should extend development time about 50% over the normal time required for intermittent agitation, but experiment before risking valuable negatives.
Stand Development —With stand development you should always pre-soak the film for about five minutes to eliminate the formation of air-bubbles. Should an air-bubble form on the film during stand development the negative will be ruined because the bubble will prevent any exchange of developer at that spot, and the effect will be to spread irregular circular patterns of up to 1/4” to 3/8 “in diameter around the bubble, ruining the frame or sheet of film. To begin development discard the pre-soak water, pour in the developer, and agitate continuously and vigorously for 60 seconds. Then, set the tank aside and leave it with no further agitation for the remainder of the development period. Development times for most films will be in the 45-60 minutes range.
 

Rick A

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If you are mixing dry chems to make stock solution, then use distilled water. You are better off using glycol for this as it will have longer shelf life once mixed. You can then mix working strength with normal tap water.
 

Ian Grant

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I make up the stock solutions for Pyrocat HD with deionised water and use tap water to make the working solutions, have been using if for quite a few years now with no issues.

It keeps well in high density plastic bottles, I've some that's 4 years old made up with water. it's important to use fresh Metabisulphite as it's the SO2 that stops the Pyrocatechin oxidising.

Ian
 
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I was always under the impression that stop bath had no effect on image-stain formation, but that the sulfite in the hypo-clearing agent does. That has been my experience as well with PMK (admittedly, not a pyrocatechol developer, but one with similar staining characteristics).

Maybe one of the Pyrocat experts can chime in here with a clarification. No use spreading inaccurate information, if the above is indeed so. Sandy?

Best,

Doremus
 

Ian Grant

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It seems to be one of those myths that Sulphite destroys the stain in a developed film or print, a bit like the myth that image stain is improved by placing the fixed negative back in the used developer, all that does is cause an overall fog stain as the dyes from oxidised developer diffuse into the film base.

I use IT-8 (an Ilford toner) sometimes it's a simple bichromate rehalogenating bleach followed by a Pyrocathechin developer, I've tried to destroy the stain on scrap prints but it's stable.

Increasing the Sulphite in the developer does prevent stain, and I think this is where the myth comes from, some Pyro developers were formulated to be stain free.

Ian