d-76 with 75g Sodium Sulfite

[pierods]

I read in an old book about a reduced Sodium Sulfite d-76, with 75 grams.

Is it any good? Should I change dev times?

 

[jochen]

there are dozens of formula which are more or less relatives of D-76 with a little bit more or less hydroquinone or metol or sodium sulfite. If you take less sodium sulfite you'll get a little bit more acuteness and a little bit coarser grain since the sulfite has dissolving properties for silver. But it acts also as a weak alkali (D-23 has only metol and sulfite), so maybe you'll have to adapt your times.

 

[pierods]

Like, more time or less time?

 

[Gerald C Koch]

The maximum solvency of sulfite for silver halide is at approximately 75 g/l. So this variation shoujld produce the finest grain provided that you use D-76 at full strength.

 

[pierods]

The maximum solvency of sulfite for silver halide is at approximately 75 g/l. So this variation shoujld produce the finest grain provided that you use D-76 at full strength.

??

Less SS produces coarser grain, isn't it?

 

[Ian Grant]

??

Less SS produces coarser grain, isn't it?

No there's an optimum point and this is close to 75-80g/l Sodium sulphite, so Adox Borax MQ and Agfa 44 (Ansco Agfa/GAF 17) use this lower amount, as does Ilford ID-68/Microphen. These developers give about 1/3 of a stop more film speed, the first two finer grain as well.

Ian

 

[pierods]

Ok, I get the point now. So at 75g/l, I get the finest grain before losing that 1/3 speed.

Why then d-76 has 100 g?

 

[Ian Grant]

Ok, I get the point now. So at 75g/l, I get the finest grain before losing that 1/3 speed.

Why then d-76 has 100 g?

Because way back in 1926/7 Eastman Kodak Research chose to use 100g/l and this stayed constant in a number of Kodak developers, the first EK Fine Grain developer, D76, D23, D25, DK20 etc.

Kodak initially began from the Wellington & Ward Buffered Borax developer formula which was known to give finer grain and a series of developers evolved with incresing Sulphite, DK50 is the closest to the W&W dveloper, DK60 & DK60a in between DK50 & D76. There were older versions of both prior to Kodak using Sodium Metaborate.

Ian

 

[pierods]

Ok, thanks!

 

[Athiril]

I just finished some tests with Kodak D-76 vs the D-76 standard formula:

Stock vs Stock.

Kodak D-76 is slightly sharper and grainier, otherwise identical results. Test was on T-Max 100.

details: http://www.photodan.com.au/2013/04/kodak-d-76-vs-homebrew-d-76-differences/


Kodak D-76: http://www.photodan.com.au/wp-content/uploads/2013/04/D76.jpg
D-76 Standard Recipe: http://www.photodan.com.au/wp-content/uploads/2013/04/PC11.jpg

 

[pierods]

I just finished some tests with Kodak D-76 vs the D-76 standard formula:

Stock vs Stock.

Kodak D-76 is slightly sharper and grainier, otherwise identical results. Test was on T-Max 100.

details: http://www.photodan.com.au/2013/04/kodak-d-76-vs-homebrew-d-76-differences/


Kodak D-76: http://www.photodan.com.au/wp-content/uploads/2013/04/D76.jpg
D-76 Standard Recipe: http://www.photodan.com.au/wp-content/uploads/2013/04/PC11.jpg

Wow!

Everybody said it's the opposite - less SS, more grain, sharper...

 

[Ian Grant]

What are you saying is Kodak D76 and what is D76 standard recipe ?

Commercial D76 is somewhere between D76 and D76d with some Boric acid alongside the Borax, but with greater buffering than the original published D76 formula. I guess that's what you're saying. The buffering is also slightly higher with commercial ID-11.

D76 wasn't designed for dilution but that's become a common practice since WWII days, so maybe the increased buffering is designed to help with stability of pH when diluted.

Ian

 

[Ian Grant]

Wow!

Everybody said it's the opposite - less SS, more grain, sharper...

That's not what he's said, he's not compared D76 with less Sulphiter, rather the commercial to the published formula.

If you reduced the sulphite you'd probably change the M-Q balance as well to achieve optimal results. Look at Abox Borax MQ, which is EFKE FR2

Ian

 

[Athiril]

What are you saying is Kodak D76 and what is D76 standard recipe ?

Commercial D76 is somewhere between D76 and D76d with some Boric acid alongside the Borax, but with greater buffering than the original published D76 formula. I guess that's what you're saying. The buffering is also slightly higher with commercial ID-11.

D76 wasn't designed for dilution but that's become a common practice since WWII days, so maybe the increased buffering is designed to help with stability of pH when diluted.

Ian

The standard recipe. You know. Not derivatives, modifications. Not D-76b/c/d/x/etc, just D-76. Which is listed on the first link I provided

Metol 2g/L
Sodium Sulphite 100g/L
Sodium Tetraborate (Borax) 2g/L
Hydroquinone 5/gL

Kodak D-76 is still 109g/L the same as the above recipe, so in order to include other ingredients, or increase one, something has to be reduced (ie: probably the Sulfite).

If it is otherwise D-76d.. 2g/L Metol, 5/gL HQ, and 8g/L Borax and 8g/L Boric Acid, logically Sodium Sulphite is 86g/L not 100g/L.

Of course the commercial stuff would also have a chelating agent.. in this case pentetic acid. The MSDS lists Boric Anhydride as the other chemical used, which is dehydrated Boric Acid.

So it should go B2O3 + 3H2O -> 2H3BO3

69.6182g + 3x~18.01528g -> 2x61.83g

Essentially, 1g of Boric Anhydride giving 1.78g of Boric Acid in solution.

Which goes on to form borates in water with the sulphite, altering the in solution formula.

Wow!

Everybody said it's the opposite - less SS, more grain, sharper...

The standard formula that I used has 100g/L Sodium Sulphite. I am certain Kodak D-76 has less than that when mixed up in solution.

Logically I highly doubt that Kodak D-76 ends up with less than 75-80g/L of Sodium Sulphite in solution. So I disagree with the fact that amounts above 75-80g/L do not provide any more effect. I am experiencing a very noticeable effect. If theory doesn't match observation, there is something wrong with it.

Given that, and if people are reporting 75g/L D-76 recipe as sharper/grainier than Kodak D-76, logically it's somewhere between the 75g/L and 100g/L value.

Split the difference and it's 87g/L.


If there is 2g/L of Boric Anhydride in Kodak D-76 bag (it still has to add up to 109g/L), that puts Sodium Sulfite at 100g/L in the bag, but in solution, if my calculation is right, that would drop sodium sulfite to 89g/L, and 5.47g/L of Borax Decahydrate equivalency (I think, if my calculation is right).

 

[martellsv]

100g/l Sodium Sulphite ?

Kodak D-76 is still 109g/L the same as the above recipe, so in order to include other ingredients, or increase one, something has to be reduced (ie: probably the Sulfite).

I have a Kodak D-76 package also has the wt % of borax penta, ( and looking and some olds MSDS...), IMHO there is no 100 gr/l, i don´t know exactly if 9o g/l or similar?... and a difference of three grs. i think won't be important, Again the difference in ph of several grs of sodium sulphite is not noticiable. i dont know if the other component is oxide boron or acid boric... but i am not sure this is relevant, to reach 109 g/l additives must be added.
Ph cuestion, i have reach ph 9,0 with my scientific phmeter in D-76, at list in this developer homemade version, and three hours after i get a Ph 8.5. i don´t know is the oxide boron is very acid because the boric acid is slightly acid only -0,3 ph when i mix it after the borax.