B&W reversal: Thiocyanate or Thiosulfate

[YoIaMoNwater]

They'll probably look OK - they will look a little greyer if viewed alongside a clear base film, but not as much as you might assume from viewing a negative of the same emulsion developed in a solvent developer. The choice of clear base will have likely been for the simple reason of making the transparencies look as good as possible when viewed alongside E-6 transparencies on a light table - BW cinema reversal stock is on a grey tricaetate base - the eye adapts surprisingly well if it has no other reference.

I also have significant issues with your experimental design - Microphen is a poor choice because of its lower activity (great for making nice negs) and built-in mild solvency. What you really need is a highly active, low fog developer to slam development to completion as efficiently as possible, to which you add just enough solvent and/ or accelerator to ensure that developer can access all the silver very quickly - as your first development time goes up (in reversal) Dmax drops due to fog, and if you cannot access and develop all the silver, your Dmin rises too.
.

Do you have any examples of 135mm TMax400 reversal processed?

As for you second comment, I understand a strong developer is needed for reversal. I'm using Microphen because I haven't seen anyone else done so but most importantly I was hoping to do reversal on films pushed 2 or 3 stops. Since I haven't seen anyone done reversal on really pushed films (2+ stops), I hoped I could use Microphen to do so. I've tried it at 1x stock but turned out my original solution was depleted. Next, I tried a 1.3x stock and it gave good results on Fomapan 400 @ 800 and Rollei Superpan 200 (not pushed). I still need to optimize further. If I wanted to do the traditional reversal processing with films shot at boxed speed then I would've done so. This particular thread was interesting for me because even at 1.3x Microphen, the TMax400 film leader was quite dark. I thought maybe the OP could experiment with silver solvent to solve this issue and I would then apply that to my protocol.

 

[Lachlan Young]

Do you have any examples of 135mm TMax400 reversal processed?

As for you second comment, I understand a strong developer is needed for reversal. I'm using Microphen because I haven't seen anyone else done so but most importantly I was hoping to do reversal on films pushed 2 or 3 stops. Since I haven't seen anyone done reversal on really pushed films (2+ stops), I hoped I could use Microphen to do so. I've tried it at 1x stock but turned out my original solution was depleted. Next, I tried a 1.3x stock and it gave good results on Fomapan 400 @ 800 and Rollei Superpan 200 (not pushed). I still need to optimize further. If I wanted to do the traditional reversal processing with films shot at boxed speed then I would've done so. This particular thread was interesting for me because even at 1.3x Microphen, the TMax400 film leader was quite dark. I thought maybe the OP could experiment with silver solvent to solve this issue and I would then apply that to my protocol.

You don't need examples of Tmax 400 that's been reversal processed to see where you are getting things wrong. If it's run correctly, it should look much like Delta 400 or Silvermax reversal processed, with slightly greyer highlights from the base if it's 135. In other words, like a good transparency with a full tonal range. If anything, Delta 400 seems to be more challenging to run in Scala - its Dmax seems to follow a normal distribution, with Dmax being considerably better at a 10 min FD time, rather than 7min 30s.

Scala 200x was spec'd to be pushed +3 and pulled -1. Quite a number of films are specified for push/ pull in Scala. That most don't go beyond +1 is likely because the Dmax loss is too visually obvious for many - a Dmax drop of the sort a +2 or +3 on Scala will produce will be quite noticeable on a light table - whereas the pull 1/ normal/ push 1 Dmax's are likely much closer perceptually. As you 'push', the fog from the FD goes up, Dmax goes down & makes your shadow speed appear to go up a bit.

You might also want to carefully read this post and this post before proceeding any further with Microphen. Microphen is nowhere near forceful enough for 'normal' reversal development, let alone push development. The accelerator component used in Scala allows for the developer to access the silver with potentially less of the problems noted for the use of silver solvents.

 

[Raghu Kuvempunagar]

Since I haven't seen anyone done reversal on really pushed films (2+ stops),

Well.. Fernando Pastor claims to have developed a "new reversal development gives no grain ISO 1600 on Fomapan 400 and little grain from 3200 to 25000 on Rollei Rpx 400 and a maximum sensivity of ISO100000". It's called Aura-R and there are some examples in the Facebook page as well as the web-site.

 

[YoIaMoNwater]

You don't need examples of Tmax 400 that's been reversal processed to see where you are getting things wrong. If it's run correctly, it should look much like Delta 400 or Silvermax reversal processed, with slightly greyer highlights from the base if it's 135. In other words, like a good transparency with a full tonal range. If anything, Delta 400 seems to be more challenging to run in Scala - its Dmax seems to follow a normal distribution, with Dmax being considerably better at a 10 min FD time, rather than 7min 30s.

Scala 200x was spec'd to be pushed +3 and pulled -1. Quite a number of films are specified for push/ pull in Scala. That most don't go beyond +1 is likely because the Dmax loss is too visually obvious for many - a Dmax drop of the sort a +2 or +3 on Scala will produce will be quite noticeable on a light table - whereas the pull 1/ normal/ push 1 Dmax's are likely much closer perceptually. As you 'push', the fog from the FD goes up, Dmax goes down & makes your shadow speed appear to go up a bit.

You might also want to carefully read this post and this post before proceeding any further with Microphen. Microphen is nowhere near forceful enough for 'normal' reversal development, let alone push development. The accelerator component used in Scala allows for the developer to access the silver with potentially less of the problems noted for the use of silver solvents.

My understanding is that the first developer just needs to be concentrated enough for reversal to work, that's why I tried it with a 1.3x Microphen stock (I tried to dissolve it to make 2x but it just wouldn't...). Thanks for the links. I don't speak or read German so it's hard to make out what the second link you posted said. What I can make out of it is the film listed and the suggested ISO. Honestly I'm just trying to figure out what went wrong with my TMax400 reversal attempt, whether it's the fact that even 1.3x Microphen wasn't strong enough or something else.

Well.. Fernando Pastor claims to have developed a "new reversal development gives no grain ISO 1600 on Fomapan 400 and little grain from 3200 to 25000 on Rollei Rpx 400 and a maximum sensivity of ISO100000". It's called Aura-R and there are some examples in the Facebook page as well as the web-site.

Thanks for these, Raghu! I kinda wish if he showed what the slides look like on a lightbox though. It seems like he played with temperature for the pushed films, which is something I haven't tried. I'm shooting a roll of Rollei Retro 80s at night with ISO 80, so will def try processing this in higher temperature.

 

[Raghu Kuvempunagar]

I kinda wish if he showed what the slides look like on a lightbox though.

You can perhaps reach out to him on his Facebook group.

IIt seems like he played with temperature for the pushed films, which is something I haven't tried.

He does two rounds of intensification post second development.

 

[Raghu Kuvempunagar]

Essentially what he's admitting is that his system cannot access the silver fast enough to develop it before overall fog grows to a level that kills Dmax.

Yes, that's right. OTOH is there any process that can reverse TMax 400 at box speed without requiring a halide solvent? Do you or anybody know of any process that has used the first developer in that famous Agfa-Gaevert patent for reversing TMax 400 at box speed and got good results? Studio 13's process, though allegedly based on that patent, is opaque and could be deviating from the patent in substantial ways. Does @Henning Serger have any insight to share on this topic?

 

[pkr1979]

Ive tried a few different developers with TMax400...

The reversal process I tried resulted in the film leader to be very dark/gray, even the border markings are quite dark. I'm wondering if it's necessary to add a silver solvent since I read somewhere that TMax400 has some silver halides deep within the emulsion that's hard to be bleached.

This is also my experience for Dokumol in particular but Dektol too. In PQ the tones where actually quite nice but too grainy. I suspect that thiosulfate or thiocyanate are necessary when using either Dokumol or Dektol. Also, what I find is that in addition to the Dietrich recipe (link first post), D-62 is a suggested developer for TMax400... that is D-19 with Thiocyanate...

What I dont understand here is how sodium sulphite affects things... such are the levels for various developers:
PQ: Sodium Sulphite 50 g (https://www.largeformatphotography....iversal-Recipe&p=553468&viewfull=1#post553468)
D-11: Sodium Sulphite 75 g
D-19: Sodium Sulphite 90 g
D-72: Sodium Sulphite 45 g

In my experience I would not add silver solvent if developing Tmax400 (exposed at 160) in PQ. I havent tried D-62 (I might try that instead of the Dietrich recipe), but have no reason to doubt the suggestion to use thiocyanate... So how does that add up consiering PQ (and D-11) contains less Sulphite then D-19...? Or did I misunderstand something here?

 

[relistan]

You really should be using D-72 at 1+1 or undiluted, if Ilford's comments on using Bromophen for reversal FD are any guide.

Also, do check the sulphite levels in D-11 and D-72.

I'm not using it at all, but that makes sense.

 

[relistan]

So, regarding the Dietrich recipe... it was from the 1980s, from the original incarnation of TMax 400. I know it was substantially reformulated sometime around what, 2002? Seems reasonable to me that the film doesn't respond in the same way and the recipe may not be the best for current TMax?

 

[relistan]

My understanding is that the first developer just needs to be concentrated enough for reversal to work, that's why I tried it with a 1.3x Microphen stock (I tried to dissolve it to make 2x but it just wouldn't...). Thanks for the links. I don't speak or read German so it's hard to make out what the second link you posted said. What I can make out of it is the film listed and the suggested ISO. Honestly I'm just trying to figure out what went wrong with my TMax400 reversal attempt, whether it's the fact that even 1.3x Microphen wasn't strong enough or something else.

I saw a good recommendation from @Rudeofus on another thread. He essentially suggested adjusting development time until you are happy with the contrast, then add solvent until the highlights are clear and then restrainer (e.g. potassium bromide) until the blacks are dark enough. I have not tried that yet, but it seems to jive with my experience so far.

 

[Raghu Kuvempunagar]

Seems reasonable to me that the film doesn't respond in the same way and the recipe may not be the best for current TMax?

Do you have any data or seen any data that informs your statement on the suitability of Dietrich recipe for current TMax films? I would be interested in such data.

 

[pkr1979]

So, regarding the Dietrich recipe... it was from the 1980s, from the original incarnation of TMax 400. I know it was substantially reformulated sometime around what, 2002? Seems reasonable to me that the film doesn't respond in the same way and the recipe may not be the best for current TMax?

Do you have any data or seen any data that informs your statement on the suitability of Dietrich recipe for current TMax films? I would be interested in such data.

This guy from 2011 seems happy enough: https://www.photrio.com/forum/threa...mulary-reversal-kit-and-tmax-400-tmy-2.74132/
But one of the folowers of that thread seems to not be completely satisfied... So there isnt really any data for that recipe with TMY2 I suppose.

Maybe D67 would be a good first developer then, and D19 a good second developer? Or maybe pyro...

 

[Lachlan Young]

Yes, that's right. OTOH is there any process that can reverse TMax 400 at box speed without requiring a halide solvent? Do you or anybody know of any process that has used the first developer in that famous Agfa-Gaevert patent for reversing TMax 400 at box speed and got good results? Studio 13's process, though allegedly based on that patent, is opaque and could be deviating from the patent in substantial ways. Does @Henning Serger have any insight to share on this topic?

Time for Occam's razor to make an appearance - the Agfa patent is defensive against any moves to use HQMS/ high temperature processing for BW reversal - just like those that propose peroxide bleaches for C-41 - none of which have made it to regular production either. Yet those patents also disclose C-41, RA-4 developers that are correct. PS13 use a single Scala machine running once a week with the same chemistry for everything. There is no indication that it has ever changed from the 'standard' Scala process - other than what seems to have been a shift to permanganate bleach some time ago. From what I have heard of the Scala machines, they use light reversal. I don't know how sensitive the process is to ingredient purity - but do bear in mind that Dmax seems to follow a normal distribution - so it'll rise as you develop more & more of the silver, but then overall fog takes over and it starts to fall. The art is determining the optimal developing time where you get the best possible Dmax for the optimal midtone gradient - while -1 development might seemingly deliver better Dmax, it comes at the cost of a softer tonal scale. Some people specify an 11 min FD time (for example) over the 10 min time (I think, I'd need to check my notes) that PS13 use for TMY-II to get a slightly brighter image for their preference.

 

[Lachlan Young]

So, regarding the Dietrich recipe... it was from the 1980s, from the original incarnation of TMax 400. I know it was substantially reformulated sometime around what, 2002? Seems reasonable to me that the film doesn't respond in the same way and the recipe may not be the best for current TMax?

2007. I think the problem is that everyone here is still trying to get a single solvent to do the job, when there's a huge set of potential accelerators as well - not just silver solvents like KSCN, DTOD etc, but various PEG's, other polyglycols and quaternary ammonium compounds. The latter may well be present in the 'right' quantities in some coating packages & would potentially (with the right developer etc) give significant acceleration effects. There was a case here recently of someone who had an interaction with residual wetting agent in a tank and one of the packagings of Agfa Aviphot 200S where the area that had interacted with the surfactant seemed to show significant development acceleration. Incorporated development accelerators were strongly suspected to be the major difference between Fuji Neopan 400 and 1600.

 

[Lachlan Young]

What I dont understand here is how sodium sulphite affects things... such are the levels for various developers:
PQ: Sodium Sulphite 50 g (https://www.largeformatphotography....iversal-Recipe&p=553468&viewfull=1#post553468)
D-11: Sodium Sulphite 75 g
D-19: Sodium Sulphite 90 g
D-72: Sodium Sulphite 45 g

Consider the dilutions - and that recipe you linked is essentially ID-62 rather than the much more concentrated PQ Universal, either way at the dilution recommended (PQ Universal 1+5), you're looking at about 30g/l sulphite - D-11 is used at full strength.

 

[Anon Ymous]

@pkr1979 D19 is a reasonable starting point as a first developer, that you can alter by adding whatever quantity of solvent you wish. Different films may require more or less solvent, some none at all. Keeping a 50% w/v solution of potassium thiocyanate is a good, practical idea. Actually, this is a recommended thing to do, since KSCN is highly hygroscopic and can easily pick a lot of water, making it very iffy to use.

 

[relistan]

Do you have any data or seen any data that informs your statement on the suitability of Dietrich recipe for current TMax films? I would be interested in such data.

No, I don't. Only from this thread. I was pointing out that the development times changed a lot and so it's possible that the film needs more or less time or more or less solvent than the original.

 

[pkr1979]

Consider the dilutions - and that recipe you linked is essentially ID-62 rather than the much more concentrated PQ Universal, either way at the dilution recommended (PQ Universal 1+5), you're looking at about 30g/l sulphite - D-11 is used at full strength.

Isnt this:

Sodium sulphite, anhydrous = 50 grams
Sodium carbonate, anhydrous = 60 grams
Hydroquinone = 12 grams
Phenidone = 0.5 grams
Potassium bromide = 2 grams
Benzotriazole (1% solution) = 20 ml
Water to 1 litre.

PQ?

How much sulphite would PQ contain compared to the others?

EDIT: There is still less sulphite when developing with PQ then the others then?

@pkr1979 D19 is a reasonable starting point as a first developer, that you can alter by adding whatever quantity of solvent you wish. Different films may require more or less solvent, some none at all. Keeping a 50% w/v solution of potassium thiocyanate is a good, practical idea. Actually, this is a recommended thing to do, since KSCN is highly hygroscopic and can easily pick a lot of water, making it very iffy to use.

Im probably going for D19/D62 - or D11... I've been told its finer grained.

 

[Raghu Kuvempunagar]

I saw a good recommendation from @Rudeofus on another thread. He essentially suggested adjusting development time until you are happy with the contrast, then add solvent until the highlights are clear and then restrainer (e.g. potassium bromide) until the blacks are dark enough.

This is great advice and Rudy knows his stuff. However, blind adherence isn't advisable. It's not the case that contrast will keep on increasing as you increase developing time. Fog might go up significantly and reduce the contrast if development is prolonged. If you try to cut the fog by increasing the concentration of the restrainer, then you're likely to sacrifice some speed. Increasing the halide solvent can clear the highlights but also lighten the midtone which might not be to your liking. It's a difficult balancing act that can't always be achieved by simplistic tuning of the variables involved.

 

[Lachlan Young]

Isnt this:

Sodium sulphite, anhydrous = 50 grams
Sodium carbonate, anhydrous = 60 grams
Hydroquinone = 12 grams
Phenidone = 0.5 grams
Potassium bromide = 2 grams
Benzotriazole (1% solution) = 20 ml
Water to 1 litre.

PQ?

How much sulphite would PQ contain compared to the others?

EDIT: There is still less sulphite when developing with PQ then the others then?



Im probably going for D19/D62 - or D11... I've been told its finer grained.

No, that's ID-62, dilute 1+1 for reversal FD. PQ Universal is a much more concentrated version. The problem with too much sulphite already in the developer is it doesn't make it easier for you to finesse solvent or accelerators - as you already have added a potentially troublesome variable with all that sulphite.

 

[Raghu Kuvempunagar]

No, I don't. Only from this thread. I was pointing out that the development times changed a lot and so it's possible that the film needs more or less time or more or less solvent than the original.

If Photo Formulary is still selling Dietrich's stuff without having tested it on the current TMax films and confirming that it gives good results, then it is a sorry story.

 

[Raghu Kuvempunagar]

Maybe D67 would be a good first developer then, and D19 a good second developer? Or maybe pyro...

I know you said this in jest. However, using a staining developer such as Pyrocat-HD as the first developer in reversal processing is a sure way to get muddy slides and a lot of stain. Note that the stain will be maximum in the highlights (making them dull) as those regions have the highest density in the negative image. If you still want to give Pyro a try, add some sulphite to kill the stain.

It's OK to use staining developer as the second developer. You get a nice brown tone.

 

[relistan]

This is great advice and Rudy knows his stuff. However, blind adherence isn't advisable. It's not the case that contrast will keep on increasing as you increase developing time. Fog might go up significantly and reduce the contrast if development is prolonged. If you try to cut the fog by increasing the concentration of the restrainer, then you're likely to sacrifice some speed. Increasing the halide solvent can clear the highlights but also lighten the midtone which might not be to your liking. It's a difficult balancing act that can't always be achieved by simplistic tuning of the variables involved.

Well, sure, you are going to have to tune all the variables a little bit. But this is a good explanation of the starting point. I was not (and neither was he) claiming this will be easy. But it's a path that makes sense about how to get to a good place.

 

[relistan]

If Photo Formulary is still selling Dietrich's stuff without having tested it on the current TMax films and confirming that it gives good results, then it is a sorry story.

It would be worth a note to them in query in the event that someone cares enough to do it.

 

[DeletedAcct1]

I've used hypo without any problems with eFKe 100 and Kodak T-Max 100. Particularly Kodak T-Max 100 yielded very good slides, excellent contrast. at 12g of hypo per liter of first developer (that was Kodak D-19).
Here the results https://www.photo.net/379849#//Sort-Newest/All-Categories/All-Time/Page-1
Though I've found that by using that quantity of hypo Agfa Apx 100 was bad. Lowering it to 1g per liter has got me good slides.
Hypo is the silver halide solvent recommended and used by Ilford so as far as I'm concerned it's good.
I know of at least a guy (Ivo Stunga - check him out on Flickr and Instagram) who has nailed the Ilford reversal method almost to perfection, by lowering the hypo quantity and optimizing the ISO of the films he's using.
Very very good results.