B&W reversal processing. Kit or dichromate bleach or hydrogen peroxide+vinegar?

mohmad khatab · Apr 23, 2020

I am very sympathetic to you and appreciate your position.
If you could come to Egypt or send any friend to me. I am ready to send you all these chemical materials for free as a gift for you in order to help you complete your experiments and tests.
I'm not joking ,,
If we assume, for example, that the British ambassador to Egypt is your uncle ((this is an imaginary assumption of course in order to simplify the idea)), only your uncle sends his driver to me and I will send with him enough to prepare 4 liters of each client's chemical acid (AGFAscala)). ( I'm not joking ).
Unfortunately, sanitary isolation is a hindrance, and the movement of aircraft is stopped.

Lachlan Young · Apr 23, 2020

Laci Toth said:
Thanks for your ideas! I need time to process all these infos as there are so many and will work out something to roll on!

This is an Agfa patent that seems to disclose what is highly likely to be the Scala development process. The MQ first developer described in the patent - not the HQMS ones - would seem like a good place to start from. The only significant change over time seems to have been the bleach being changed to acidified permanganate with the added Calgon to sequester the manganese. The Scala process definitely works well with Delta 100 in 120 & sheets.

Laci Toth · Apr 23, 2020

Lachlan Young said:
This is an Agfa patent that seems to disclose what is highly likely to be the Scala development process. The MQ first developer described in the patent - not the HQMS ones - would seem like a good place to start from. The only significant change over time seems to have been the bleach being changed to acidified permanganate with the added Calgon to sequester the manganese. The Scala process definitely works well with Delta 100 in 120 & sheets.

Thanks! Gonna have a look into it!

Raghu Kuvempunagar · Apr 23, 2020

Lachlan Young said:
you don't necessarily need a solvent in the first developer - a development accelerator such as PEG 1500 is seemingly much more effective.

Lachlan Young said:
This is an Agfa patent that seems to disclose what is highly likely to be the Scala development process. The MQ first developer described in the patent - not the HQMS ones - would seem like a good place to start from.

Lachlan, have you actually used the MQ first developer described in the Agfa patent without and with PEG and found that it gives better highlights with PEG? The MQ first developer in the patent does use PEG, I was wrong. Interestingly, they use PEG 1500 for the MQ first developer and PEG 400 for the HQMS first developer.

mohmad khatab · Apr 23, 2020

[QUOTE = "Lachlan Young، post: 2273188، member: 9175"] هذه براءة اختراع من Agfa يبدو أنها تكشف ما يحتمل أن يكون عملية تطوير Scala . يبدو مطور MQ الأول الموصوف في براءة الاختراع - وليس HQMS - مكانًا جيدًا للبدء منه. يبدو أن التغيير الهام الوحيد بمرور الوقت هو تغيير المبيض إلى برمنغنات حمضية مع Calgon المضافة لعزل المنغنيز. عملية سكالا تعمل بشكل جيد بالتأكيد مع Delta 100 في 120 ورقة. [/ QUOTE]
شكرا لك يا أخي العزيز على هذه الوثيقة الهامة. بارك الله فيك.
فيما يتعلق بالمطور الأول: تتم كتابة براءة الاختراع في صيغ للمطور الأول ، ويعتمد الإصدار الأول على الهيدروكينون العادي وهو متاح بسهولة.
شكراً لك يا أخي العزيز على هذه الوثيقة المهمة. بارك الله فيك.
فيما يتعلق بالمطور الأول: تتم كتابة براءة الاختراع في صيغ للمطور الأول ، ويعتمد الإصدار الأول على الهيدروكينون العادي وهو متاح بسهولة.

Lachlan Young · Apr 24, 2020

Raghu Kuvempunagar said:
Lachlan, have you actually used the MQ first developer described in the Agfa patent without and with PEG and found that it gives better highlights with PEG? Interestingly, the patent doesn't make any such claims for MQ first developer. It doesn't even give the results for MQ + PEG. It only compares MQ with a new first developer, D1, and says that a specific combination of D1 with PEG and an antifoggant gives better results than MQ.

Not yet, because I have had dozens of other things to do than look for reasonably priced PEG 1500 - and I currently cannot access the location I would prefer to use to mix it.

Edit: have now found a source of PEG 1500, will probably try the developer some time in the next month or so - it is not a high research priority for me.

The patent describes the MQ first developer as a 'commercially available first developer' and uses it as a comparator point which produces suitable Dmax and Dmin to compare the HQMS first developers to. If you read the results tables it suggests that the HQMS developer gets close in results to the standard MQ one but never really betters it. The point is that the MQ first developer is pretty heavily hinted at as what they were selling for Scala labs & the 'D1' formulation was an attempt to reduce the use of HQ (just as Xtol was trying to do for negative development at the time).

mohmad khatab · Apr 25, 2020

This is the most powerful and cheapest formula at the same time.
(Concentrate Solution) can live indefinitely.
AGFA Neutol WA
Distilled or deionized water 400 ml 60 ° C
EDTA Na4 ......................10g
Potassium Sulfite....... 225 g or ( 225g sod. sulfie)
Hydroquinone .............45g
Phenidone................... 1.5g or (15g Metol )
Potassium Carbonate 45 g
Potassium Hydroxide 15 g
Potassium Bromide ...10 g
Anti Fog ..........................0.5 g (Option).
Water up to 1 liter Dilution = 1: 9

koraks · Apr 25, 2020

mohmad khatab said:
( 225g sod. sulfie)

This will not dissolve in the initial 400ml of water. It'll only dissolve when the volume is made up to 1 liter and even then it'll take a while to get it all into solution.

mohmad khatab · Apr 25, 2020

koraks said:
This will not dissolve in the initial 400ml of water. It'll only dissolve when the volume is made up to 1 liter and even then it'll take a while to get it all into solution.

Yes, my brother ,,
You are kind of right.
It is really difficult to dissolve.
But when it came time to add (potassium hydroxide) in the order of the recipe, I did the following.
I put the solution in a glass container, and I made a hot water bath and raised the temperature of the solution to more than 80 degrees Celsius.
I added very quietly, stirring constantly until all the solution blended and became perfect.
- I measured the amount of the solution and found it very close to one liter, so I increased the water until the solution reached one liter.

Raghu Kuvempunagar · Apr 25, 2020

mohmad khatab said:
This is the most powerful and cheapest formula at the same time.
(Concentrate Solution) can live indefinitely.
AGFA Neutol WA
Water up to 1 liter Dilution = 1: 9

Mohmad, are you recommending this as first developer in reversal processing of b&w film? If you have used it and compared it against more well-known reversal first developers, can you please tell what are its advantages?

mohmad khatab · Apr 25, 2020

Raghu Kuvempunagar said:
Mohmad, are you recommending this as first developer in reversal processing of b&w film? If you have used it and compared it against more well-known reversal first developers, can you please tell what are its advantages?

I have already prepared that recipe. It can be used in the first and second developer as well
In the first developer it is necessary to add (2 grams of potassium thiocyanate) and if it is not available then you can add 5 grams of sodium thiosulfate, in the second developer you do not add anything ,,
I added (2 grams of potassium thiocyanate), and it got very good negativity with high intensity and excellent contrast.
The important question:
Was this formula worth it ...
The answer is brief. Yes, she really deserves all this patience.
- You will get negative development at a very high intensity
Greetings .

Raghu Kuvempunagar · Apr 25, 2020

mohmad khatab said:
Was this formula worth it ...
The answer is brief. Yes, she really deserves all this patience.

Nice! Enjoy.

mohmad khatab · Apr 25, 2020

This is a version from the same developer ( work soltion) that works without Dilution

AGFA - Neutol WA
Potassium Sulphite.................. 60 g - this is equivalent to 48 g Sodium Sulphite
Hydroquinone ..........................12 g
Phenidone ...............................0.4 g ( metol ...4g)
Potassium Carbonate ..............12 g
Potassium Hydroxide ................4 g ( sod. Hydroxiide ..3g)
Potassium Bromide ...................2.67 g (NaBr .....2.3g)
Water to 1 litre
ـــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــ
You will make the solution in two containers, each one (half a liter).
It comes on the first package and throws inside it with (KSCN 2g) ..or. ( 5g Sodium thiosulfate) , and you write on that bottle the title (first developer)
The second package (the other half-liter) can be used (second developer)

Jeremy Saint-Peyre · May 21, 2020

Donald Qualls said:
with some thiosulfate added for the first developer

Hello Donald, i'm doing black and white reversal with FOMA R-100 super-8, i'm bleaching with sulfuric acid (900ml 7%) and potassium permanganate (900ml 0,2%) for 5min30 at 20 degrees. The bleach is almost complete but not quite. I fear that if i extend the bleaching time it will damage the emulsion (if i double the potassium permanganate to 0,4%, it melt in the second developer).

Could sodium thiosulfate in the first developer (Ilford Multigrade 1+9, 1L, 20°C) help the bleaching process as it will start to erase the anti-halo layer ?

Thank you very much !

Donald Qualls · May 21, 2020

@Jeremy Saint-Peyre I don't have a definitive answer for you. I've only done B&W reversal a few times, and I used dichromate/sulfuric bleach, rather than permanganate. Dichromate hardens the emulsion, so this problem doesn't arise with that bleach (but it's probably hard to buy or legally dispose of dichromates in Europe these days). I would have to suggest testing your extended bleach time with a throw-away strip of (the same) film (ideally, fully fogged and developed), to see how the emulsion handles extended bleaching time.

I wouldn't expect thiosulfate in the first dev to change your outcome, in this case, because it would remove undeveloped halide, but your bleach step needs to remove developed silver. Thiosulfate in the first dev is added to clear highlights (and overall lighten the final positive image) by reducing the amount of halide remaining for the fogging and second developer to turn into silver.

Jeremy Saint-Peyre · May 21, 2020

@Donald Qualls thank you, i'll go this way, testing, always testing

B&W reversal processing. Kit or dichromate bleach or hydrogen peroxide+vinegar?

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