Sodium Thiocyanate substitute?

[ZorkiKat]

Can Sodium Thiosulphate substitute for Sodium Thiocyanate? This substitution is mentioned in two references by R. E. Jacobson, in two different books published by Focal Press. One can be found in "Focal Guide to Home Processing". If this is so, what would be appropriate amount of Thiosulphate needed replace Thiocyanate, weight by weight, in a first developer formula?

 

[Anon Ymous]

Start with double the amount of thiocyanate that a formula calls for. Of course, this is only a rule of thumb and some experimentation will be needed.

 

[Ian Grant]

It depends on what the formula and overall process is. Ralph's father Curt (Kurt) Jacobson was the chemist and a founder of Pavelle in Epsom (later to become Durst UK) and worked on colour processing. (This is in the Colour sub forum).

Ian

 

[Anon Ymous]

... (This is in the Colour sub forum)...

Oops, didn't notice that it was in the Colour forum, I nearly always click the "new posts" link and though it was about bw reversal 1st developer.

 

[Rudeofus]

Of all the compounds going into an E6 FD, the Thiocyanate is probably the most easy to get your hands on, unless you already work with some easier to mix substitute formula (Watkins factor?). But even if you find a source for all components of Watkins factor E6 FD, how do you get Citrazinic Acid and CD-3 for the color developer, if you can't get a Thiocyanate?

 

[Photo Engineer]

If thiosulfate were a good substitute, then it would have been used. Sorry, I would not try this switch and as noted by Rudi above, the other chemicals are far harder to get.

PE

 

[Ian Grant]

We still don't have clarification from the OP. While I don't have Ralph Jacobson's1978 book it's unlikely to be an E6 formula as the first was published in the BJP (weekly magazine) in 1980 and included in the processing section of the 1981 BJP Annual. No colour first developer uses Thiosulphate, that includes the Eastern European formula.

Curt Jacobson in the last (18th( edition of Developing suggests ID-36 (at 1+1) + Hypo for B&W processing - 8g/l Sodium thiosulphate for HP3 & HP4 and 12 g/l for FP4. That's taken from Ilford as it matches my Ilford Manual of Photography which says 8 g/l for FP3. The latest Lilford Reversal Processing PDF is similar but using modern developers and available on their website.

As Jacobson includes a comparison of 3 B&W first developers, the substitution is Sodium Thiosulphate 4x by weight of the amount of Sodium Thiocyanate.

Ian

 

[Photo Engineer]

US patent 55948604 shows Ammonium Thiocyanate in the first developer. This patent was granted to EK in 1998. Thiosulfate was never used.


PE

 

[ZorkiKat]

Thanks for the replies. I was planning to use the substitute for the FD in colour reversal processing. What will be the effect if thiocyanate was skipped on the FD? Thiocyanate isn't readily available here.

 

[Rudeofus]

Thanks for the replies. I was planning to use the substitute for the FD in colour reversal processing. What will be the effect if thiocyanate was skipped on the FD? Thiocyanate isn't readily available here.

Thiocyanate works as developer accelerator, without it you'd have to vastly extend FD times.

Just a quick question: you aren't by any chance trying to process E-6 with some self mixed FD, then reexpose and run through C-41 or RA-4 process, are you?

 

[Photo Engineer]

Thanks for the replies. I was planning to use the substitute for the FD in colour reversal processing. What will be the effect if thiocyanate was skipped on the FD? Thiocyanate isn't readily available here.

If there is no strong solvent in the FD, the Dmin will probably be murky and the contrast might be off (high). There will probably be crossover. This was the case when I worked last with color reversal processes.

PE

 

[ZorkiKat]

Thiocyanate works as developer accelerator, without it you'd have to vastly extend FD times.

Just a quick question: you aren't by any chance trying to process E-6 with some self mixed FD, then reexpose and run through C-41 or RA-4 process, are you?

Reexpose or fogging bath (I still have some fogging baths left over from E6 kits), and develop in modified RA-4 developer. I am planning to use D19 as the first developer, and plan to add the solvent to it.

 

[Photo Engineer]

Be sure to post examples.

PE

 

[trendland]

Reexpose or fogging bath (I still have some fogging baths left over from E6 kits), and develop in modified RA-4 developer. I am planning to use D19 as the first developer, and plan to add the solvent to it.

Thanks for the replies. I was planning to use the substitute for the FD in colour reversal processing. What will be the effect if thiocyanate was skipped on the FD? Thiocyanate isn't readily available here.

ZorkiKat let me first ask : Why ?
Let me secondly have a guess : You won't
buy kits from manufacturers to avoid troubble with exausted FD ? And then you have to buy a complete new kit.
You want to make experiments with E6?
You want to save money? You just want to see what will hapen ?

So you want first add sodium thiosulphate as an addition to Kodak D-19 ? First reformulate D-19 than get in use to watkins formula and change the
(little complicate) FD from watkins?
Whow - great idea - but I have a feeling from missunderstanding this tread .
But if I Do Not so .... as Rudeofus stated - you could get in problems to get
the other RAW chemicals !
As PE. stated you might get very special colors (is this your intention?)

Hopefully I am not wrong but try first the following method (instead of mixing D-19
with a chemical compound mentioned from watkins FD formula)

Try Kodak D-82:

Water 52/C.................................750ml
Wood alcohol ...............................48ml
Metol. ...........................................14g
Sodium Sulfite (anhydr.)..............52,5g
Hydroquinone. .............................14g
Sodium Hydroxide..........................8,8g
Potassium Bromide........................8,8g
Water to make...........................1000ml

Be cautious with Sodium Hydroxide
(be sure you know this) first information
you should start own research !!!!!
If the developer is too strong you have abilities to change alcohol - and use water. It is a formula to use it as stock
solution ( not very stabile - some days)

This D-82 was in use as a maximum energy developer for wratten hypersensitiven panchromatic plates
in the very past.

The raw chemicals are total ordinary you
should get them simple.

The developer time is on you. A startpoint could be 6min. at 20/C.

But it should be to short.I would advice
you to rise up the temperature higher and you got it whithin your 6min. you know from normal E6 process (6'min15").
To avoid "murky" Dmin/wrong contrast/
as a result from this : to avoid color crossings - you have to change delution
you should find out corrections to developer times.
I am quite shure it may work much better
than a mix with D-19 !

Bon Chance

PS: This is a "try and error method" .

 

[trendland]

If there is no strong solvent in the FD, the Dmin will probably be murky and the contrast might be off (high). There will probably be crossover. This was the case when I worked last with color reversal processes.

PE

PE - to get sure not have a mistake cause by missunderstanding the attention of the op let me short ask?

" is sodium thiocyanate in FD existenciell important due to chemical concern
(reaction of couplers in layers) with
following CD ?"

I got it im mind that it is responcible to
contrast in bw developer (FD)......????

with regards

 

[trendland]

PE - to get sure not have a mistake cause by missunderstanding the attention of the op let me short ask?

" is sodium thiocyanate in FD existenciell important due to chemical concern
(reaction of couplers in layers) with
following CD ?"

I got it im mind that it is responcible to
contrast in bw developer (FD)......????

with regards

ähhmm .....sorry to ask again I know as well as the contrast in the bw negative
of an E6 film after FD is the key to correct colors in CD.
My question was in the direktion to avoid
sodium thiocyanate totally - of cause the
contrast with other FD must be in a range of comparision.

with regards

 

[Photo Engineer]

Thiocyanate is used as a solvent in the E6 FD as well as most other reversal FDs to aid in cleaning out the Dmin in the reversed image. It acts as a solvent to increase negative Dmax and lower negative fog thus having the reverse effect after reversal.

PE

 

[trendland]

Thiocyanate is used as a solvent in the E6 FD as well as most other reversal FDs to aid in cleaning out the Dmin in the reversed image. It acts as a solvent to increase negative Dmax and lower negative fog thus having the reverse effect after reversal.

PE

Easy to imagine - first make the room clean - than let the new guest in : FD !

Fog in the bw picture before reversal !

Never thought to this before - but nescessary to know - Ammonium Thyocianate (US Patent ) / Sodium Thyocianate in use from watkins.

Thanks a lot.


with regards.

 

[trendland]

Oh - NO

CD of cause!!!!!!!

(FD makes the room dirty - CD is the new guest)

with regards

failure by tapping

 

[trendland]

Thiocyanate works as developer accelerator, without it you'd have to vastly extend FD times.

Just a quick question: you aren't by any chance trying to process E-6 with some self mixed FD, then reexpose and run through C-41 or RA-4 process, are you?

Well - ...Rudeofus that would imply to
use normal c41 chemistry as CD.
Or cross processing of E6 (without
reexposure/reversal exposure/reversal bath? ) So we are talking about
Real E6 experimental use ?

I had cross processed E6 many years ago! I was not amused of .

with regards

 

[Rudeofus]

Reexpose or fogging bath (I still have some fogging baths left over from E6 kits), and develop in modified RA-4 developer. I am planning to use D19 as the first developer, and plan to add the solvent to it.

I was quite sure that you were going into that direction, I guess it's easier to get D-19 and RA-4 CD than E6 kits. Here is what you could do in order to make reasonable progress (all those who consider deviations from standard E6 process apostasy punishable by death: this post is not for you, just ignore it, I wrote it for folks without access to correct processing chems and non-standard raw chems):

1. E6 BLIX is about double strength of RA-4 CD, otherwise not that much different. BLIX for at least 8 minutes. If you have access to RA-4 chems, maybe the same source can give you C-41 bleach & fixer. The latter would be much more effective than double strength RA-4 BLIX, but both should work. If you want to know whether your BLIX concoction works, develop a fully exposed E6 test clip in whatever paper developer you can find until it is completely developed, which should be the case after 5-10 minutes. Then throw it in your BLIX and wait for it to completely clear. The test clip was likely opaque even before you developed it, this opaqueness comes from the anti halation layer which is realized as colloidal silver layer, which goes away during BLIXing. If your BLIX concoction doesn't clear your developed film within 10 minutes, you need to find out what went wrong.
2. about CD: E6 CD is an even more violent thug than E6 FD: compared to RA-4 CD it contains about twice the amount of CD-3, and it typically operates around pH 12 vs 10.25. This means you have to mix RA-4 CD at twice the strength, then add Trisodium Phosphate until pH is good. How do you know how much you need without a pH meter? Look at the color of your E-6 CD: if it's too alkaline, it oxidizes quickly in air, which you can observe by its strong discoloration. Add only as much Trisodium Phosphate as it takes to slightly change the color appearance of your double strength RA-4 CD. A quick test whether your E6 CD works is running a small, fully exposed test clip through the process only with the steps CD, wash, BLIX (or bleach&wash&fix), wash. Such a test clip must be completely dense, much denser than normal black areas of slide film, more like: completely opaque to light.
   
3. about FD: E6 FD is a violent thug, much more active than all B&W developers I am aware of. The real formula (like shown (there was a url link here which no longer exists) and (there was a url link here which no longer exists)) is sort of hard to compare, since no mainstream B&W developer uses HQMS as secondary developer. The Watkins Factor E6 FD uses Phenidone (and loads of it!! ) and HQ, so it's easier to compare to D-19, if we assume that Phenidone replaces Metol at roughly 1:10 ratio. Can you find a source of Metol in your place, such as D-23 developer? Yes, you will need some solvent or your E6 FD times will go through the roof. Maybe you can make Sodium Thiosulfate work for you. If you can find a source of Potassium Thiocyanate: don't worry if it's pricey, you only need about 1 g/l, a tiny stash will likely last you a long time. If you can't find KSCN, maybe you could use Rodinal stand development as E6 FD step as shown in (there was a url link here which no longer exists).
   
4. Because of this colloidal silver based anti halation layer there is no way to check E6 FD without going through the whole process including BLIX or bleach&fix, this is why I mention FD towards the end of this list. You must have a working CD and BLIX before you can test whether FD works properly.
   
5. RA-4 chems don't contain Formalin, but E-6 emulsions need it. Mix a STAB with Photo Engineer's formula from (there was a url link here which no longer exists) and be done with it.

These instructions should bring you to a point where you can at least get some viewable color slides with B&W developer, RA-4 chems, Potassium Thiocyanate and Trisodium Phosphate. Once you have these, and if the results look off, there are ways to fine tune the process. Once you post your scans we can help you dial in the process.

 

[Photo Engineer]

In the references that Rudi gives above, the first one is by far the better one.

Don't forget that the E6 CD has lots of solvents and competers and is very active.

PE

 

[trendland]

I was quite sure that you were going into that direction, I guess it's easier to get D-19 and RA-4 CD than E6 kits. Here is what you could do in order to make reasonable progress (all those who consider deviations from standard E6 process apostasy punishable by death: this post is not for you, just ignore it, I wrote it for folks without access to correct processing chems and non-standard raw chems):

1. E6 BLIX is about double strength of RA-4 CD, otherwise not that much different. BLIX for at least 8 minutes. If you have access to RA-4 chems, maybe the same source can give you C-41 bleach & fixer. The latter would be much more effective than double strength RA-4 BLIX, but both should work. If you want to know whether your BLIX concoction works, develop a fully exposed E6 test clip in whatever paper developer you can find until it is completely developed, which should be the case after 5-10 minutes. Then throw it in your BLIX and wait for it to completely clear. The test clip was likely opaque even before you developed it, this opaqueness comes from the anti halation layer which is realized as colloidal silver layer, which goes away during BLIXing. If your BLIX concoction doesn't clear your developed film within 10 minutes, you need to find out what went wrong.
2. about CD: E6 CD is an even more violent thug than E6 FD: compared to RA-4 CD it contains about twice the amount of CD-3, and it typically operates around pH 12 vs 10.25. This means you have to mix RA-4 CD at twice the strength, then add Trisodium Phosphate until pH is good. How do you know how much you need without a pH meter? Look at the color of your E-6 CD: if it's too alkaline, it oxidizes quickly in air, which you can observe by its strong discoloration. Add only as much Trisodium Phosphate as it takes to slightly change the color appearance of your double strength RA-4 CD. A quick test whether your E6 CD works is running a small, fully exposed test clip through the process only with the steps CD, wash, BLIX (or bleach&wash&fix), wash. Such a test clip must be completely dense, much denser than normal black areas of slide film, more like: completely opaque to light.
   
3. about FD: E6 FD is a violent thug, much more active than all B&W developers I am aware of. The real formula (like shown (there was a url link here which no longer exists) and (there was a url link here which no longer exists)) is sort of hard to compare, since no mainstream B&W developer uses HQMS as secondary developer. The Watkins Factor E6 FD uses Phenidone (and loads of it!! ) and HQ, so it's easier to compare to D-19, if we assume that Phenidone replaces Metol at roughly 1:10 ratio. Can you find a source of Metol in your place, such as D-23 developer? Yes, you will need some solvent or your E6 FD times will go through the roof. Maybe you can make Sodium Thiosulfate work for you. If you can find a source of Potassium Thiocyanate: don't worry if it's pricey, you only need about 1 g/l, a tiny stash will likely last you a long time. If you can't find KSCN, maybe you could use Rodinal stand development as E6 FD step as shown in (there was a url link here which no longer exists).
   
4. Because of this colloidal silver based anti halation layer there is no way to check E6 FD without going through the whole process including BLIX or bleach&fix, this is why I mention FD towards the end of this list. You must have a working CD and BLIX before you can test whether FD works properly.
   
5. RA-4 chems don't contain Formalin, but E-6 emulsions need it. Mix a STAB with Photo Engineer's formula from (there was a url link here which no longer exists) and be done with it.

These instructions should bring you to a point where you can at least get some viewable color slides with B&W developer, RA-4 chems, Potassium Thiocyanate and Trisodium Phosphate. Once you have these, and if the results look off, there are ways to fine tune the process. Once you post your scans we can help you dial in the process.

......Great! !!!
....sorry to missunderstand something in
wrong direktion first.
I understand it as reformulation of D19.
PE. makes it clear to me - it is only the
addition of one solvent due to avoid fog.

D19 is discontinued - I just find out.
But it is with simpel formula.

So I would withdraw my recomandation
to D-82 ........it was just the idea to avoid any mixing in D-19 formulation.
But the more reason is : It is also a strong
developer but I got no idea to grain with
it to E6?
And alternative E6 with grainy slides at the end of full process should be the recomandation to no one.

with compliments

 

[Rudeofus]

trendland, if you want nice, sharp slides with fine grain and accurate colors, you have to mix the correct soup, whatever it takes. If you could get great slides from D-19, D-82 with some house hold chems, then Kodak would have loved to sell just that.

As far as I have understood this, ZorkiKat has no access to E6 kits or fancy raw chems, so I am trying to help him get at least some results with a fair amount of fine tuning and testing. The advice I gave above describes the McGyver E6 process, not anything a decent lab should do.

@ZorkiKat : AFAIK Suvatlar ships photochemistry internationally, maybe try contact him whether Philippines are an option for him. If you only need KSCN and/or Na3PO4, shipping costs should be reasonable and no drug/terrorism charges will be pressed against you.

 

[trendland]

trendland, if you want nice, sharp slides with fine grain and accurate colors, you have to mix the correct soup, whatever it takes. If you could get great slides from D-19, D-82 with some house hold chems, then Kodak would have loved to sell just that.

As far as I have understood this, ZorkiKat has no access to E6 kits or fancy raw chems, so I am trying to help him get at least some results with a fair amount of fine tuning and testing. The advice I gave above describes the McGyver E6 process, not anything a decent lab should do.

@ZorkiKat : AFAIK Suvatlar ships photochemistry internationally, maybe try contact him whether Philippines are an option for him. If you only need KSCN and/or Na3PO4, shipping costs should be reasonable and no drug/terrorism charges will be pressed against you.

.....Rudeofus....R u d e o f u s... !

Everything is fine !

So let me say.....if I would ever be intended to mix the "correct soup " wich
should have some abilitys to get better results than from comercial labs I will
have to wait a long time - perhaps!
Until the quality from this labs reaches a
point of catastrophe.
May be we all will see these days?
If I would intend to have more acurate
chemistry than Kodak E6 /Fuji Hunt E6 designed from my own personal research/experience I could have some
problems - I would say.
1) I would need venture capital within
a volume of (estimated) not less than
$ 65.000.000 .
2) I would need a comercial property AND - all kind of regulatory authorisation
3) I would need to build up a business park with a small factory (due to production) with costs from 2/3 of my whole risk capital.
4) I would need several years of time to
R+D work with the help of a phantastic
team of scientific experts.
5) As it goes not with some house hold chems AND the standard of Kodak and Fuji has to be topped I would need some
chemical experts in addition with experience to common film work practice.
6 ) As I am no chemical expert and in addition wich
absolute no experience in concerns
of such a complicate and ambitioned
project - I would need chemical experts
like you Rudeofus perhaps PE is willing also.
What a great Idea.

But at least how to get this ammound of
venture capital ?
Potential funders would state : "Sorry dear fellows - THAT risc is much to high"

But they named it "Risc Capital".

Rudeofus ....seriously : You missunderstood me - Your recomandation was just GREAT !!
As you would allow me to say so.
AND - I am not criticized you in concern
with grainy slides - I have criticized
myself due to D-82 .

Everything is fine you are wellcome.



with regards


PS: I will not intend to have better E6 developement with alternative E6.
I just practice comercial labs with E6.

But I am preparing to the day x.