Agfa-Gavaert Reversal Developer

[Raghu Kuvempunagar]

The patent https://patents.google.com/patent/US6350563
describes a "commercially available first developer containing Hydroquinone" for B&W reversal processing. Any idea what is the capacity of this developer? And is there a replenisher for it?

 

[mohmad khatab]

The patent https://patents.google.com/patent/US6350563
describes a "commercially available first developer containing Hydroquinone" for B&W reversal processing. Any idea what is the capacity of this developer? And is there a replenisher for it?

I told you about that patent two days ago that you got by chance some time ago, I said you already have it.
But you weren't interested in it. And you kept talking about it in a rather negative way until you almost convinced me that it was a useless patent.
What happened to you, you left?
Why did you change your mind?
Were you too quick to judge the document as useless or what?

 

[Raghu Kuvempunagar]

All I told you was I've seen this patent before and it's meant for Agfa Scala film which is no longer available. Everything else is your imagination. Anyway, Facebook messenger conversation on technical matters across language is bound to be misunderstood.

 

[AgX]

This patent is interesting already by its sheer existence. To my knowledge Agfa-Gevaert (in contrast to Orwo) never commercialized a b&w reversal processing kit, neither for consumers nor commercial users. It thus is about an modified formula for the Scala process, run worldwide back then only by a handful of commercial labs.

 

[Raghu Kuvempunagar]

This patent is interesting already by its sheer existence. To my knowledge Agfa-Gevaert (in contrast to Orwo) never commercialized a b&w reversal processing kit, neither for consumers nor commercial users. It thus is about an modified formula for the Scala process, run worldwide back then only by a handful of commercial labs.

It's interesting for several reasons including the use of PEG as development accelerator. Any educated guess on its capacity and shelf-life? Can it be used several times without replenishment?

 

[otto.f]

All I told you was I've seen this patent before and it's meant for Agfa Scala film which is no longer available. Everything else is your imagination. Anyway, Facebook messenger conversation on technical matters across language is bound to be misunderstood.

ADOX Scala Kit for B/W Slide Processing to mix 2000 ml - fotoimpex.com analogue photography

The ADOX SCALA Kit only has two parts (plus an optional clear bath), radically simplifying the black&white reversal process. Simply mix the developer and bleach 1+1 with ...

www.fotoimpex.com

https://www.fotoimpex.de/shop/images/products/media/66896_5_PDF-Datasheet.pdf

 

[Raghu Kuvempunagar]

ADOX Scala Kit for B/W Slide Processing to mix 2000 ml - fotoimpex.com analogue photography

The ADOX SCALA Kit only has two parts (plus an optional clear bath), radically simplifying the black&white reversal process. Simply mix the developer and bleach 1+1 with ...

www.fotoimpex.com

https://www.fotoimpex.de/shop/images/products/media/66896_5_PDF-Datasheet.pdf

Thanks but how's this related to my question in OP?

 

[Lachlan Young]

The patent https://patents.google.com/patent/US6350563
describes a "commercially available first developer containing Hydroquinone" for B&W reversal processing. Any idea what is the capacity of this developer? And is there a replenisher for it?

It states 'tank solution' - which usually means replenisher + starter. As for capacity & replenishment, you'll need to determine that in your process environment via sensitometry & the formulae in the SPSE Handbook on replenisher design.

 

[otto.f]

ADOX Scala Kit for B/W Slide Processing to mix 2000 ml - fotoimpex.com analogue photography

The ADOX SCALA Kit only has two parts (plus an optional clear bath), radically simplifying the black&white reversal process. Simply mix the developer and bleach 1+1 with ...

www.fotoimpex.com

https://www.fotoimpex.de/shop/images/products/media/66896_5_PDF-Datasheet.pdf

You stated: “Agfa Scala film which is no longer available”. The developer and the film are valiable

 

[Raghu Kuvempunagar]

You stated: “Agfa Scala film which is no longer available”. The developer and the film are valiable

Yes, I meant the original Agfa Scala 200 reversal film. Neither that film nor the first developer described in the patent are available commercially today. Adox's Scala kit that is available today is different.

 

[Raghu Kuvempunagar]

It states 'tank solution' - which usually means replenisher + starter. As for capacity & replenishment, you'll need to determine that in your process environment via sensitometry & the formulae in the SPSE Handbook on replenisher design.

Ok. Agfa-Gavaert first developer has relatively low amount of sulphite (11g/l) compared to other known first developers (usually >= 50g/l). I wonder if this has any adverse effect on both shelf-life of the developer as well as reuse.

 

[AgX]

You stated: “Agfa Scala film which is no longer available”. The developer and the film are valiable

No, the film went under with Agfa's consumer division. And Agfa never made such developer, at least they never listed it.


Much later Adox made a film which they offer under two designations, one of them is Adox Scala 160.

Later again they bought a current film from Agfa, applied a special treatment to it and offer it under two designations, one of them is Adox Scala 50.

So Adox now have two Scala-designated films in their range.

 

[Lachlan Young]

Ok. Agfa-Gavaert first developer has relatively low amount of sulphite (11g/l) compared to other known first developers (usually >= 50g/l). I wonder if this has any adverse effect on both shelf-life of the developer as well as reuse.

I'm pretty sure it's there largely as a preservative. Tank life will probably have been aimed to be inline with other similar professional-lab-oriented systems (i.e. C-41 and E-6) - and replenishment rates within a similar range. At the end of the day, Agfa's bottom line will have been that they wanted to persuade people to invest in a Scala processing machine - and that means trying to make it not seem any more difficult to run than other processes already installed. Nothing is in the developer formula unintentionally.

 

[mohmad khatab]

Mr. Raghu was quick to judge this patent when I submitted it to you, you said it was designed for specific films only, but the patent authors did not explicitly say so - they mentioned AGFA200, as an example but not limited to, ( That's what I understood), and they also didn't say that any other movie couldn't be processed using that format.
- It is completely different from the (ORWO4185) formula, which its creators said was designed only for (UN52) films, despite that, it succeeded in developing most of Ilford's products except for (HP5).

- This is a really very important patent, especially since it was issued just two years before the official closure of Agfa, and this makes it considered the last patent issued by that great company.

In general, I think that someone should take the initiative to test this formulation contained in the patent.

Why are you inquiring about a starting solution and a Replenisher solution? We are amateurs, we don't care much about that.
- Also the developer contains etidronic acid is a very powerful sequestering agent. you have to combine it with EDTA, and your developer will stay fresh much longer
By pure chance, I have an ingredient (5-methylbenzotriazole)
I think this element is a very key ingredient in that formula.
Also, I can provide (hydroxyethane-diphosphonic acid) or (etidronic acid) the same element but with another name.
I asked a supplier who specializes in laboratory chemistry, and he said it was an affordable ingredient.
- There is only one ingredient left that I still did not find because most of the chemistry companies are closed due to the blessed Eid Al-Fitr holiday, which is (polyethylene glycol,)
But I think that it is an available element, I think, I saw this name circulating on the page of the group of laboratory chemistry dealers in Egypt.

 

[Raghu Kuvempunagar]

Later again they bought a current film from Agfa, applied a special treatment to it and offer it under two designations, one of them is Adox Scala 50.

Is the Scala 50 version of the film also given speed boost treatment? Pre-flash reduces shadow contrast and DMax of slide film both of which are generally not desirable for slide film. So I was under the impression that Scala 50 is HR-50 without speed boost.

 

[AgX]

Yes, I too expected it to be offered in the original, untreated version.
But Adox on their site explicitely say that HR-50 and Scala 50 are the exact same film. (Just differently designated. For the Silvermax/Scala 160 Mirko argued that this type of marketing was urged by the few labs doing reversal processing.)

Easy to find out though.

 

[Raghu Kuvempunagar]

I'm pretty sure it's there largely as a preservative. Tank life will probably have been aimed to be inline with other similar professional-lab-oriented systems (i.e. C-41 and E-6) - and replenishment rates within a similar range. At the end of the day, Agfa's bottom line will have been that they wanted to persuade people to invest in a Scala processing machine - and that means trying to make it not seem any more difficult to run than other processes already installed. Nothing is in the developer formula unintentionally.

Thanks Lachlan. Another question. The "commercially available first developer containing Hydroquinone" in the patent has 2.0g of Nitrilotriacetic acid in it. However, the solubility numbers are a little puzzling. According to one source, solubility in water is 1.28g/l. Several other sources say it is less than 1g/l. Is the solubility of NTA higher in alkaline solution?

 

[AgX]

I'm pretty sure it's there largely as a preservative. Tank life will probably have been aimed to be inline with other similar professional-lab-oriented systems (i.e. C-41 and E-6) - and replenishment rates within a similar range. At the end of the day, Agfa's bottom line will have been that they wanted to persuade people to invest in a Scala processing machine - and that means trying to make it not seem any more difficult to run than other processes already installed. Nothing is in the developer formula unintentionally.

Yes, this perfectly makes sense. As I already statet, this patent formula was intented for a handful of commercial labs, and thus it most likely inherits features to just please this clintele.

 

[Lachlan Young]

Thanks Lachlan. Another question. The "commercially available first developer containing Hydroquinone" in the patent has 2.0g of Nitrilotriacetic acid in it. However, the solubility numbers are a little puzzling. According to one source, solubility in water is 1.28g/l. Several other sources say it is less than 1g/l. Is the solubility of NTA higher in alkaline solution?

Yes. Start from the perspective that it was formulated by highly able chemical engineers with fairly significant R&D resources & not by an amateur dabbler in a garden shed.

 

[doctorpepe]

Mr. Raghu was quick to judge this patent when I submitted it to you, you said it was designed for specific films only, but the patent authors did not explicitly say so - they mentioned AGFA200, as an example but not limited to, ( That's what I understood), and they also didn't say that any other movie couldn't be processed using that format.
- It is completely different from the (ORWO4185) formula, which its creators said was designed only for (UN52) films, despite that, it succeeded in developing most of Ilford's products except for (HP5).

- This is a really very important patent, especially since it was issued just two years before the official closure of Agfa, and this makes it considered the last patent issued by that great company.

In general, I think that someone should take the initiative to test this formulation contained in the patent.

Why are you inquiring about a starting solution and a Replenisher solution? We are amateurs, we don't care much about that.
- Also the developer contains etidronic acid is a very powerful sequestering agent. you have to combine it with EDTA, and your developer will stay fresh much longer
By pure chance, I have an ingredient (5-methylbenzotriazole)
I think this element is a very key ingredient in that formula.
Also, I can provide (hydroxyethane-diphosphonic acid) or (etidronic acid) the same element but with another name.
I asked a supplier who specializes in laboratory chemistry, and he said it was an affordable ingredient.
- There is only one ingredient left that I still did not find because most of the chemistry companies are closed due to the blessed Eid Al-Fitr holiday, which is (polyethylene glycol,)
But I think that it is an available element, I think, I saw this name circulating on the page of the group of laboratory chemistry dealers in Egypt.

 

[doctorpepe]

Don’t know if anyone will read this but I have formulated the agfa first developer based on the patent specifications and used it for reversal processing with very great effectiveness. I’m too tied up with work to post results right now but I will say that it works beautifully with Fomapan-R at box speed and with Ilford PanF+ at ei25-32. I’ve used it with Ilford FP4+, Delta 100 and Ilford Ortho Plus, all of which gave fair results (less dmax). Tri-x, Double x, Acros II and Fomapan 100 Classic were all relative failures with poor thin image quality and/or excessive fogging. Films with more inherent emulsion contrast seem to do very well with reversal development. First development times must be customized to each film (Fomapan-R takes 12 min@70F while Ilford PanF takes 18 min@70F). The process I use has a light reversal rather than chemical and uses chromium bleach. The hardest material to source was the hydroquinone sulfonic acid sodium (or potassium) salt. I am currently tinkering with the ingredients to come up with a replenisher so I don’t have to toss the original developer. Will send more at some future point.

 

[john_s]

Don’t know if anyone will read this but I have formulated the agfa first developer based on the patent specifications and used it for reversal processing with very great effectiveness. I’m too tied up with work to post results right now but I will say that it works beautifully with Fomapan-R at box speed and with Ilford PanF+ at ei25-32. I’ve used it with Ilford FP4+, Delta 100 and Ilford Ortho Plus, all of which gave fair results (less dmax). Tri-x, Double x, Acros II and Fomapan 100 Classic were all relative failures with poor thin image quality and/or excessive fogging. Films with more inherent emulsion contrast seem to do very well with reversal development. First development times must be customized to each film (Fomapan-R takes 12 min@70F while Ilford PanF takes 18 min@70F). The process I use has a light reversal rather than chemical and uses chromium bleach. The hardest material to source was the hydroquinone sulfonic acid sodium (or potassium) salt. I am currently tinkering with the ingredients to come up with a replenisher so I don’t have to toss the original developer. Will send more at some future point.

Interesting, hydroquinone sulfonic acid sodium (or potassium) salt is in some Moersch developers (film and paper) that appear to have some desirable characteristics (the potassium salt in these cases).

Does anyone know anything more about it? Should we be trying to source some of it?

 

[Anon Ymous]

Interesting, hydroquinone sulfonic acid sodium (or potassium) salt is in some Moersch developers (film and paper) that appear to have some desirable characteristics (the potassium salt in these cases).

Does anyone know anything more about it? Should we be trying to source some of it?

It's an ingredient of E6 FD and Suvatlar stocks it.

 

[DeletedAcct1]

How about the first developer in the Scala kit?
Is it like the first developer in the patent?
Why don't we ask Adox if the first Scala developer can be produced as a stand alone product in bottle of say 1, 5, 10 and 20 liters?
Maybe more concentrated, like say with a 1:4 factor...

 

[relistan]

Don’t know if anyone will read this but I have formulated the agfa first developer based on the patent specifications and used it for reversal processing with very great effectiveness. I’m too tied up with work to post results right now but I will say that it works beautifully with Fomapan-R at box speed and with Ilford PanF+ at ei25-32. I’ve used it with Ilford FP4+, Delta 100 and Ilford Ortho Plus, all of which gave fair results (less dmax). Tri-x, Double x, Acros II and Fomapan 100 Classic were all relative failures with poor thin image quality and/or excessive fogging. Films with more inherent emulsion contrast seem to do very well with reversal development. First development times must be customized to each film (Fomapan-R takes 12 min@70F while Ilford PanF takes 18 min@70F). The process I use has a light reversal rather than chemical and uses chromium bleach. The hardest material to source was the hydroquinone sulfonic acid sodium (or potassium) salt. I am currently tinkering with the ingredients to come up with a replenisher so I don’t have to toss the original developer. Will send more at some future point.

Definitely interested in your results when you get time!