Filmotec/Orwo B&W Reversal processing

[Ian Grant]

Ian Grant submitted a new resource:

(there was a url link here which no longer exists) - Filmotec/Orwo B&W Reversal processing

First Developer ORWO 829
Solution 1:
Water (35°C) 750.0 ml
Sodium sulphite 25.0 g
Phenidone 0.2 g
Hydroquinone 10.0 g
Sodium carbonate 20.0 g
Potassium bromide 6.0 g
Potassium thiocyanate 6.0 g
Solution 2:
Water (20°C) 125.0 ml
Sodium hydroxide 5.0 g
After cooling down solution 1 pour
solution 2 into it and
Make up with water to 1 litre


Bleaching bath ORWO 833
Water 750.0 ml
Potassium dichromate 10.0 g
Sulphuric acid. conc....

(there was a url link here which no longer exists)

 

[dr5chrome]

..of all these public/published recipes posted here, this is likely the best one to start with. Modifications should be made depending on the film used.

Reversal processing is with the effort especially if you are scanning the film.

regards
dw

www.dr5.com

 

[Ian Grant]

It goes against all DW's own recommendations in a forthcoming publication where he advises not to use a solvent in the first developer, thiosulphate or thiocyanate. However the film manufacturers have rather more expertise in the field of Reversal processing, so this a modern modern/current 1st Developer recommend by Filmotec. However it's remarkably similar to ID-62 (used 1+1) + Thiocyanate (instead of Thiosulphate), plus additional bromide instead of Benzotriazole.

Ian

 

[dr5chrome]

what a mind job

...wow, i just looked back on this one:confused::confused:. It would be best if you didn't put words in my mouth Mr Grant. ! It sounds like you are a little jealous. It's one thing to post already published Recipes, then create one from scratch like we did... and dont worry your little head, one day we will publish dr5.

I didn't say anything other than this post of yours might have some promise. I also don't care who you got this gibberish from, it's still a bad Recipe! Your attitude is unprofessional, unbecoming and personally I don't think you know what you are talking about. Why don't you post something original rather than what you find in a book? I don't appreciate your little childish games here! Do you have anything better to do? I have more knowledge on this subject than most and certainly than you.

If you would bother to be professional and ask why I make the claims I do you would understand the facts and understand the 'whole' picture, it's called a 'new' way of thinking and discovery, something you are too plugged up to figure out.

regards

dw

It goes against all DW's own recommendations in a forthcoming publication where he advises not to use a solvent in the first developer, thiosulphate or thiocyanate. However the film manufacturers have rather more expertise in the field of Reversal processing, so this a modern modern/current 1st Developer recommend by Filmotec. However it's remarkably similar to ID-62 (used 1+1) + Thiocyanate (instead of Thiosulphate), plus additional bromide instead of Benzotriazole.

Ian

 

[Ian Grant]

...wow, i just looked back on this one:confused::confused:. It would be best if you didn't put words in my mouth Mr Grant. !

David, you really should try reading your own words in the 3rd Edition of The Darkroom Cookbook. Chapter 13 page 141: "However, going against tradition David Wood recommends not using anything with thiocyanate or thiosulfate in the first developer. Instead, he recommends the use of Kodak D-11. All three first developer formulas are given in Formulas: Reversal Processing."

So read that again, if I say "It goes against all DW's own recommendations in a forthcoming publication where he advises not to use a solvent in the first developer, thiosulphate or thiocyanate" I'm not wrong. I think your relevant words are "David Wood recommends not using anything with thiocyanate or thiosulfate in the first developer.".

So you see I haven't put any words in your mouth.

In fact tradition is divided as to whether to add a silver solvent, there are many formulae that add one but also quite a few that don't.

In your rant I notice that yet gain you state "I also don't care who you got this gibberish from, it's still a bad Recipe". All I'll say to that is that according to you all the major Photographic companies published and widely used formulae are rubbish, OK some of these are older now discontinued processes from companies who ceased trading, but others like this Orwo formula are still in daily use, and they all share a lot of similarities.

It would be more professional on your part if you stopped constantly make sniping personal attacks when people don't agree with your narrow minded and blinkered approach to Reversal Processing. No-one is rubbishing your DR5 process, just stating that there are a number of alternative avenues that people can pursue.

Ian

 

[Ian Grant]

also don't care who you got this gibberish from, it's still a bad Recipe!

Filmotech are the modern incarnation of ORWO, which in turn evolved from the East German parts of Agfa after WWII. They work closely with Calbe who now produce what was once Orwo chemistry.

This Formula is current & up to date, and is recommended for the Reversal processing of their Motion picture films. So it beggars belief that you constantly refer to respected Manufacturers recommended formulae as "Bad Recipes", particularly when you quite obviously haven;t tried many of them.

You have done the same in a number of other threads, despite the fact that Ron Mowrey (PE) has told you they worked and were used in Hollywood labs for years.

Sometimes to go forward you have to go backwards first, and so it's vital when doing research to know what's been done before. The truth is that all these Formulae will work, but some will obviously be far better than others.

Many people here on APUG are interested in these formulae and a number have requested I post more. It gives other people some ideas of where to start their own experiments.

Ian

 

[Ian Grant]

Alessandro, there are 3 silver solvents which are typically used in B&W reversal first developers, Thiosulphate, Thiocyanate and now DTOD which is C6H14O2S2 3,6-Dithiaoctane-1,8-diol. Of these Thiosulphate is the least common and it's not used in any modern commercial developers (1940's onwards), and only Ilford recommend using it, in their reversal processing data sheet.. At one time Ilford recommended using the first developer from the Dufaycolor process for B&W reversal, that uses Thiocyanate.

I've not used Dokumol but it's quite similar to Ilford PQ Universal or May & Baker (Champion) Suprol. Suprol was widely used for commercial B&W reversal processing and there was a very detailed data-sheet available in the 70's, you had to add 4 gm's per litre of Sodium or Potassium Thiocyanate to a 1+4 working solution.

So if you can standardise on a good readily available normal PQ print developer use it at twice the normal working strength, ie 1+4 instead of 1+9, and try it with Thiosulphate & then Thiocyanate but you'll almost certainly get better results with the Thiocyanate.

The Orwo/Filmotec 829 first developer is a similar PQ developer but has approx double the Hydroquinone and increased Bromide which will give give better contrast & Dmax. Potentially it looks to be an excellent First developer.

Somewhere I have a short trouble shooting guide for reversal processing, I'll post here on APUG in the next few days.

Ian

 

[Ian Grant]

I've got excellent results, at least to my eyes, using Tetenal Eukobrom and Dokumol with 2,5g of thiosulphate in 250ml of working solution.

Dunno why thiocyanate will yield better results than thiosulphate.

I don't have the books with me that go into the advantages/disadvantages of Thiocyanate/Thiosulphate but Thiocyanate is more effective and so you use less. I guess it's also for the same reason that Thiocyanate was used in extra fine grain developers rather than Thiosulphate, it produces less dichroic fog during processing.

Over the years I've used both but with different developers, so that clouds my judgement, but you are right excellent quality is achievable using a print developer & Thiosulphate.

Ian

 

[Photo Engineer]

Thiosulfate decomposes slowly in solution and loses potency therefore making the developer more variable. Also, the risk of dichroic fog is increased. As Ian mentions, hypo is also less efficient at the same concentration as thiocyanate.

PE

 

[Ian Grant]

Yes, and the extra Bromide is a very common part of a B&W Reversal First developer. I'm in the middle of number crunching these developers as I write. Both the formulae using Thiosulphate add it just before use.

Ian

 

[Mick Fagan]

Ian, with step 7 of the process, how important is the intensity of the second exposure, can you over do it without too much of a problem?

In other words, allowing for most home darkroom lighting set-ups, what do you think would be a suitable situation.

Mick.

 

[Ian Grant]

Mick, the secret is adequate exposure, Ilford's recommendation is "30-60 seconds at 46cm/18in from a 100-watt tungsten lamp" but go on to say 2-4 times this is safe. In the past I've also used a 275w Photoflood but the distance is increased to about 6ft (2 metres). So there's plenty of le-way.

Heavy reversal exposure particularly to sunlight can cause major problems with the image partially inverting giving a sort of solarised effect.

Ian

 

[Mick Fagan]

Thank you Ian, I have in the past done quite a fair bit of reversal processing of FP4 and FP4+.

I have always used a tungsten 60W bed lamp stuck on my darkroom wall for the second exposure. Generally I have taken about 15 seconds to get the film off the reel, then I expose for around 20 seconds each side, then the film is in the light as I re-wind back on the reel. The exposure was obviously all right as my films came out quite well.

I have an application in the new year for B&W trannies and I actually was looking on Apug when my search turned this thread up.

Except for two chemicals I have everything, so I'll get them and have a go next year.

Mick.

 

[Ian Grant]

Alessandro if you use a Paterson or other translucent reel it is possible to re-expose while the film's still on the reel.

I do have manufacturers chemical reversal baths, also Fogging Developers, some of the chemicals are not that easy to get hold of. I'll have to dig them out, I've not put them in my database yet. There's Kodak FD-72 which uses sodium dithionite, but it's not very stable once mixed and only lasts a couple of hours. Stannous chloride and derivatives of hydrazine can be used and also Sodium Sulphide or alkaline Thiourea (Thiocarbamide). I'll post some ideas for you as soon as I get time to sort them out.

Ian

 

[Photo Engineer]

Ian;

There is the old standby, Stannous Chloride for reversal. The others you mention such as Sodium Sulfide and Thiourea are really baths that precipitate Silver Sulfide and cause a brown-black image to form. These can interfere with imaging as they can react with the Silver Sulfate formed in the bleach if washing is insufficient.

The Stannous Chloride is currently used in E6 and is not very stable. Before this, E4 used t-Butyl Amine Borane which was quite toxic.

As for overexposure with light, I have never heard of it. If the silver is properly developed in the first developer, you cannot overexpose using light. If that were possible, then the reducing reversal baths would be impossible to control and even worse for this "solarization" effect.

Kodak only warns about overheating the emulsion and causing reticulation, or splashing the bulb and shattering it. The only place I know of that you can overexpose during reversal is Kodachrome processing.

PE

 

[Ian Grant]

Ron (PE), the effects of overexposure at the reversal exposure are quite well documented, (of course it can happen with normal negatives as well), but I think it's harder to achieve with a tungsten light source, and you may not easily spot the early effects. All commercial processing lines of course use a controlled re-exposure, so it's virtually impossible under those conditions. However it will occur quite easily with re-exposure to daylight/sunlight, and at it's worst does cause Solarization.

It's the blue/UV end of the spectrum that causes the damage, the residual silver halides left in the emulsion after first development and bleaching are effectively no longer Panchromatic, and their speed has dropped s significantly, they are now most sensitive to Blue/UV light and so 30 seconds to 4 minutes with a tungsten 100 - 275 watt bulb is in comparative terms very low compared to the same length of exposure to daylight or worse still sunlight. It could be a big mistake to do the reversal exposure in a room lit by daylight.

Kodak actually use the same phenomenon for their direct reversal copying films, and Ansel Adams made his famous image with a black sun which demonstrates the effect very dramatically.

I haven't spent much time on the direct reversal developers yet, but any of them will cause problems if the Silver Sulphates aren't fully removed, after the bleach bath. One function of the Sulphite or Metabisulphite clearing bath is to act as a wash-aid to help remove any semi-soluble silver salts from the emulsion, May & Baker's Reversal process actually used "Thiolim" their proprietary wash aid as the clearing agent.

Ian

 

[Photo Engineer]

Ian;

The conventional wisdom (not set in stone though) was that a first developer developed all of the exposed negative image and so there was nothing left to cause problems with the reversal exposure. And, that is why the re-exposure either via chemical means or light was considered to be going to completion!

Now, I can agree with you, but in experiments I have never ever seen the re-reversal or solarization demonstrated via light or chemical means. This does not mean that it can't happen and the documentation you cite supports that. I think we have enough information betwee us to cause a warning flag for people to be cautions then. Thats about all I can say.

Thanks.

PE

 

[Ian Grant]

You need to think of the emulsion left after bleaching etc as Virgin emulsion. So it needs so much exposure to reach Dmax that and more is your exposure to completion.

It's a bit like frying an egg, you might want the yoke runny so you pull it off the heat early, you might want it solid - that's our Cooking / Development to completion, you can keep going not a lot changes for quite a long time, then suddenly it's becoming burnt.


So yes you expose to completion but that's been tested for.

Ian

 

[Photo Engineer]

You might consider this then.

The E6 color developer, after the fogging bath, is a developer that goes to completion. If there was virgin emulsion there that was not developed in the first developer, you would have a colored dmin. That was prima facia evidence in many reversal processes that the reexposure by any means went to completion. But that was also true in B&W.

Since real B&W reversal process development was abandoned at many companies about 50 years ago, it seems that there may be a lot left to do.

PE

 

[Ian Grant]

Since real B&W reversal process development was abandoned at many companies about 50 years ago, it seems that there may be a lot left to do.

PE

Fuji continued exploring the B&W reversal process well into the 80's. They looked particularly at the bleach baths to find a less toxic more stable alternative, these include two we didn't mention in a different post - one being Cerium. They also looked at some fogging agents we haven't touched on

Agfa were still working in the same fields until much more recently, probably right up to their collapse. So there must still be improvements that can be made. It would be interesting to compare just how how much the last official Scala process differs from the Gevaert Formula for the early 50's Dia Direct films, which of course Agfa continued with after the merger and eventually evolved into Scala.

Ian

 

[Photo Engineer]

Ian;

None of these came to fruition though. The only ones that I know of were the Kodak Persulfate bleach and I'm not sure how far that really went. Yes, there were copper bleaches and Ferric Citrate bleaches and Peroxide bleaches, as well as many fogging baths. There were even several organic bleaching agents developed and patented.

I know of two new developer formulations that Kodak was working on as well, and Liquidol is the result of one approach doing the best I can without really exotic chemistry. None of these, in spite of research, truly went into the development or release stages at any company. The B&W reversal market was just not there.

Even the E6 market has dried up pretty much, and that is why there has been no real change to the E6 process and product line for some years. Again, there were several improvements that died in the last 15 years or so.

I would guess that if had analog continued to grow, there would have been a family of direct positive films that took a standard negative B&W process. The technology was there and that was the preferred direction with many in the field due to the simpler process and compatibility with the B&W neg-pos systems out there. High speed reversal emulsions eliminated the need for any bleach or clear bath entirely! No reversal step was needed either.

PE

 

[Ian Grant]

Ron, I've just been sent something which clearly indicates Agfa had switched away from the Dichromate bleach by the middle of 2000, this matches the research data, which is quite detailed and extremely useful.

"For approx. 6 months for the SCALA process a Bleach-bath is used, which no longer contains Dichromate and the replacement is ecologically substantially less precarious." It was in German so I've it's abit literal. Goes on to say Tetenal's B&W Reversal kit has also dropped Dichromate, this is in a communication from Agfa-Gevaert AG themselves, in January 2001.

Ian

 

[Photo Engineer]

I believe it Ian, but I've never seen it here in the US, only the Kodak kit, and there was no mention of it at EK.

It might be one of the persulfate bleaches or something like that. IDK.

I do know that the US Bureau of Mines worked on refining silver ores to remove silver metal and silver salts and developed a series of what we would term bleach, blix and fix baths that were supposedly usable on depleted ores and were supposedly "friendly". I have tried a number of them that I gleaned from patents and other literature. They were not photographically useful IMHO.

There is a whole body of unpublished (AFAIK) work on bleaches, blixes and fixes that were left dangling when projects were shut down, and one of the major players died suddenly. This was in the mid '90s.

PE

 

[Ian Grant]

It's a permanganate bleach. Used with precautions (very diluite) will not soften the emulsion too much.

Not sure which bleach you mean, Scala or Tetenal ?

Agfa's research was into alternatives to Permanganate & Dichromate, and it was ongoing for quite a number of years and culminated in the change from Dichromate around 2000.

I'll hopefully test the bleaches in the Spring, I still have a lot of reading to do and then need to analysi all the potential avenues to pursue. So far I have already made some important steps into gaining full control of the B&W reversal process.

I'll keep you posted, I won't be keeping things secret.

Ian

 

[Ian Grant]

I think Tetenal.

That's quite possible, I've not seen the Tetenal kits for quite a while now.

Ian