Adox scala kit

[Raghu Kuvempunagar]

Thanks for your offer. We appreciate it. But this is not as easy as it seems at first sight: Testing films and chemicals in such a good and reliable way that the results can be published in data sheets for customers is not easy and needs lots of experience and expertise. Therefore we need to know the testers personally and for years, as we have absolutely to know the quality of their work. Because we as a company are responsible for the product and potential recommendations for further non-ADOX films.

I understand your concerns. Your approach is at odds with Ilford's approach for XP2 Super. Ilford's datasheet for XP2 Super says they don't recommend processing it in B&W chemistry. However, the datasheet also mentions that several users have used conventional processing and reported good results. They even published a blog article by a user who developed the film unconventionally, ie in B&W chemistry. I don't see why you can't take a similar approach for your reversal kit.

 

[runswithsizzers]

I can certainly understand why Adox would be very reluctant to pass on user's diy testing results as part of their official documentation, justifiably so - but...

The kit is designed and packaged to be used under circumstances that are not necessarily controlled laboratory conditions, right? I would think some real-world testing, with feedback, could be useful to Adox. Such feedback might result in minor improvements to the packaging or instructions, and a better reception upon initial release of the kit (?)

 

[Lachlan Young]

The kit is designed and packaged to be used under circumstances that are not necessarily controlled laboratory conditions, right? I would think some real-world testing, with feedback, could be useful to Adox. Such feedback might result in minor improvements to the packaging or instructions, and a better reception upon initial release of the kit (?)

Going by what I remember seeing in their Instagram stories, that was done at the start of the year

AFAIK Scala has historically been more about 35mm than any other format.

Maybe for Dia Direct, but Scala was offered in at least 135/ 120/ 4x5 formats. Photostudio 13 will run up to 8x10 through the Scala process - you can use Delta 100 etc.

 

[DeletedAcct1]

The main chemical innovation is the new bleach process, which is much more user and environmentally friendly than currently used options.
ADOX - Innovation in Analog Photography.

There are essentially three chemicals that can be used as a reliabile bleach: dichromate, permanganate and cerium, all of which are acidified with sulfuric acid (or any of their salts).
I'm not considering peroxide and copper.
I'm wondering what is used in the kit.

 

[Donald Qualls]

There are essentially three chemicals that can be used as a reliabile bleach: dichromate, permanganate and cerium, all of which are acidified with sulfuric acid (or any of their salts).
I'm not considering peroxide and copper.
I'm wondering what is used in the kit.

I've also read that a rehalogentating bleach with chloride ion donor (for instance, ferricyanide plus table salt) will produce halide that's soluble in ammonia, where undeveloped bromo-iodide is not. Not sure I want to use ammonia directly in my darkroom, but this would work and would be much more environmentally friendly than any of the sulfate or sulfuric acid based bleaches, and less prone to going bad before it reaches the end user than peroxide/acid (likely also less prone to redeposition of silver causing staining).

 

[DeletedAcct1]

I've also read that a rehalogentating bleach with chloride ion donor (for instance, ferricyanide plus table salt) will produce halide that's soluble in ammonia, where undeveloped bromo-iodide is not. Not sure I want to use ammonia directly in my darkroom, but this would work and would be much more environmentally friendly than any of the sulfate or sulfuric acid based bleaches, and less prone to going bad before it reaches the end user than peroxide/acid (likely also less prone to redeposition of silver causing staining).

Unfortunately it's not that,
https://www.facebook.com/PhotoKlassikInternational/posts/314216925915597
The bleach as you can see is still permanganate based.

 

[Lachlan Young]

Unfortunately it's not that,
https://www.facebook.com/PhotoKlassikInternational/posts/314216925915597
The bleach as you can see is still permanganate based.

It might have a better means of manganese sequestration - there are Agfa patents from the late 90's that cover various approaches to making better permanganate bleaches that last fairly well. It wouldn't surprise me if it has common ancestry with late period Agfa research.

There are several interesting aspects in that image - the first developer is supplied as a single stock solution, as is the bleach (very interesting) and the clearing bath. The second developer is 1+9 (which may argue against it merely being repackaged Adox/ Agfa paper developer), as is the fixer. What it makes clear is that it is possible to make a single solution bleach, but also that the first developer probably cannot be made more concentrated.

 

[Donald Qualls]

That bleach bath is also about the right color for an EDTA based rehal bleach, but there isn't an ammonia bath present, so yep, appears to be permanganate. Which also has the disadvantage of softening the emulsion, vs. dichromate which hardens it. Probably the only thing "more environmentally friendly" with permanganate bleach is it doesn't release chromium (either hexavalent or the much less hazardous trivalent) into the environment. Permanganate ions are still pretty nasty, but they're not under a near-ban by the EU.

 

[DeletedAcct1]

It might have a better means of manganese sequestration - there are Agfa patents from the late 90's that cover various approaches to making better permanganate bleaches that last fairly well. It wouldn't surprise me if it has common ancestry with late period Agfa research.

There are several interesting aspects in that image - the first developer is supplied as a single stock solution, as is the bleach (very interesting) and the clearing bath. The second developer is 1+9 (which may argue against it merely being repackaged Adox/ Agfa paper developer), as is the fixer. What it makes clear is that it is possible to make a single solution bleach, but also that the first developer probably cannot be made more concentrated.

Yeah, sodium hexametaphosphate 20gr per liter of working solution permanganic acid bleach, which justifies also the single bleach solution. Works pretty well.

 

[Lachlan Young]

Yeah, sodium hexametaphosphate 20gr per liter of working solution permanganic acid bleach, which justifies also the single bleach solution. Works pretty well.

I suspect that's probably what it is - or a similar sequestrant (there may have been more effective ones than were disclosed). I think that the Adox kit is somewhat different developer-wise from the full size Scala process - I understand it's supposed to deliver near neutral colour with HR-50, whereas the Photo Studio 13 run Agfa Scala process delivers a warmer tone.

 

[Raghu Kuvempunagar]

Unfortunately it's not that,
https://www.facebook.com/PhotoKlassikInternational/posts/314216925915597
The bleach as you can see is still permanganate based.

Interestingly, the first developer is to be used at 30C whereas the bleach at 20C.

BTW is the kit meant to be used for only 4 rolls of film?!!

 

[Raghu Kuvempunagar]

I've also read that a rehalogentating bleach with chloride ion donor (for instance, ferricyanide plus table salt) will produce halide that's soluble in ammonia, where undeveloped bromo-iodide is not.

@Donald Qualls: Can you provide a reference for some work which has actually used ferricyanide plus table salt followed by Ammonia for bleaching in reversal processing and found that it works well?

 

[Raghu Kuvempunagar]

I think that the Adox kit is somewhat different developer-wise from the full size Scala process - I understand it's supposed to deliver near neutral colour with HR-50, whereas the Photo Studio 13 run Agfa Scala process delivers a warmer tone.

It could be using the same first developer but a different second developer.

 

[Donald Qualls]

@Donald Qualls: Can you provide a reference for some work which has actually used ferricyanide plus table salt followed by Ammonia for bleaching in reversal processing and found that it works well?

Sorry, I can't. I read that here on Photrio, I think it referred back to something from Photo Engineer (Ron Mowrey), but I just mentally filed the technique, I didn't link the conversation. It would be easy enough to test -- take test film through developer and stop bath, but don't fix, then bleach in ferricyanide with sodium chloride until the film has gone back to a uniform "milky halide" state -- that part's proven technique. Then put the treated film into clear ammonia (3% ammonium hydroxide solution) -- this latter step is the one in question. What I read was that the ammonia water will dissolve the silver chloride, but not the bromo-iodide. The obvious disadvantage is the need to do the final bleach step under a fume hood...

 

[Lachlan Young]

It could be using the same first developer but a different second developer.

Possibly - but the working temperature of the first developer suggests that the Dimezone-S/ HQMS + 4g/L PEG 400 + 100mg/L 5-methylbenzotriazole first developer innovation (that runs at 30oC) laid out in the Agfa Scala patent may have been the starting point - rather than the extant first developer for Scala that uses PEG 1500 & runs at 20oC. Not least as it offers an apparently significant Dmax increase for minimal impact on Dmin. As this new developer has been formulated largely for one film, it will have enabled a degree of optimisation to be done. The second developer looks suspiciously like it uses Ascorbate as an ingredient - a Neutol Eco variant?

 

[Team ADOX]

Going by what I remember seeing in their Instagram stories, that was done at the start of the year

That is generally right, Lachlan. We've done several testing runs over many months by very trustworthy and longtime customers, which we also know personally. They have also given us feedback.

ADOX - Innovation in Analog Photography.