Ansco 130 From Dektol = Dektol 130?

[chuckroast]

So I made the mistake of buying the 130 kit from PF to "try" it and I discovered that I really liked it. While subtle, the shadow separation is definitely better to my eye than Dektol. Moreover, the keeping properties seem to be as claimed.

The problem is that I still have a ton of the "new" Dektol (the not muddy brown kind) and I don't want to just sit there. "Well", sez me, "according to various geniuses here and there, the formula are quite close for the two but one needs to add glcyin." The problem is, "How much"? It then occurred to me that if I carefully selected an amount of Dektol stock to match the ingredient concentrations in 130 as best I could, I could top it off so that these ingredients were now the same as 130.

So I ginned up a spreadsheet to fiddle with this and came up with the following:

That is to say, if I start with 0.71 liters of Dektol stock and add the components shown in the far right column,
I should get what amounts to Ansco 130 stock once I top it off with water to 1 liter.

However, some notes are in order:

• While I have mixed up a liter of this "Dektol 130", I haven't actually tried it yet.
• I converted the formula to use Sodium Carbonate Monohydrate, because that's all I have here.
• This does assume that the D-72 formula is close enough to Dektol for these substitution calculations.
• Ignore the Benzotriazole cell on the left. That's just there to remind to to try it once I get this working.

 

[Alex Benjamin]

Took me a while to figure out why 710 ml of D-72 until I realized it was because of the metol.

 

[chuckroast]

Took me a while to figure out why 710 ml of D-72 until I realized it was because of the metol.

Yeah, I fiddled with it in the spreadsheet until I got there.

 

[Don_ih]

If you got it to mix together, it should work fine. You can see that the Glycin and large increase in Potassium Bromide are what actually make the difference.

 

[Alex Benjamin]

That is to say, if I start with 0.71 liters of Dektol stock and add the components shown in the far right column,

Not sure you're going to get all of them to dissolve in an already mixed solution, especially one at room temperature. Perhaps mix the missing components in the 290 ml of water first, then add that to the D-72.

 

[chuckroast]

Not sure you're going to get all of them to dissolve in an already mixed solution, especially one at room temperature. Perhaps mix the missing components in the 290 ml of water first, then add that to the D-72.

I raised the temp of the stock Dektol to about 120F with a heated mixing plate to get each component in solution.

 

[Alex Benjamin]

I raised the temp of the stock Dektol to about 120F with a heated mixing plate to get each component in solution.

 

[chuckroast]

I just printed some stuff with my first batch of "Dektol 130" as described above.

'Happy to report that this scheme works just as expected.

I now have a path to both consume my considerable stash of packaged Dektol at a very slow pace since the '130 formula at 1:1 can process around 100 8x10 equivalents with long tray and storage life. This is unlike the Dektol I was using at 1:2 as one session developer.

 

[Craig]

Have you done any side by side prints to compare the Dektol to the "Dektol 130"? I'd be curious how much of a difference there is.

 

[chuckroast]

Have you done any side by side prints to compare the Dektol to the "Dektol 130"? I'd be curious how much of a difference there is.

Not of the same print, so only anecdotally, but they seem pretty similar when printing.

 

[chuckroast]

Have you done any side by side prints to compare the Dektol to the "Dektol 130"? I'd be curious how much of a difference there is.

Let me correct what I wrote above.

"Dektol 130" seems quite similar to Ansco 130 when viewing the resulting prints, though I've not directly compared them for the same print.

Neither of these is exactly the same thing as Dektol proper. The 130 variants show more separation in the shadows and better restraint in the highlights. The differences are subtle, though. It's not night and day.

 

[mshchem]

Fascinating information. I have a bit of a stockpile of Dektol, now I would need to get to work printing. Maybe when the weather gets nasty

 

[chuckroast]

Fascinating information. I have a bit of a stockpile of Dektol, now I would need to get to work printing. Maybe when the weather gets nasty

Note that my calculations are based on turning D-72 into Ansco 130, but I am actually applying this to packaged Dektol. The one unknown is what role the sequestering agent in that packaged Dektol might play, if any.

Would be most interested in hearing from someone who understands the chemistry of the sequestering.

 

[mshchem]

Note that my calculations are based on turning D-72 into Ansco 130, but I am actually applying this to packaged Dektol. The one unknown is what role the sequestering agent in that packaged Dektol might play, if any.

Would be most interested in hearing from someone who understands the chemistry of the sequestering.

Only thing I can remember about sequestration agents was EDTA, but thats not likely here. CALGON is the other that comes to mind. ???? Not sure what is in Dektol.

 

[john_s]

FWIW the MSDS shows

1% - 5% Polyphosphoric acids, sodium salts (68915-31-1)

which is Calgon in some markets (but not in others. At least that's how it used to be)

 

[chuckroast]

FWIW the MSDS shows

1% - 5% Polyphosphoric acids, sodium salts (68915-31-1)

which is Calgon in some markets (but not in others. At least that's how it used to be)

Doesn't seem like that would be material in my case as I mix Dektol with distilled water.