sodium sulfite - metol only film developer

[el wacho]

Hi, if I wanted to make a film developer with 1g metol per litre, how much is enough sod. Sulfite to maintain a borax like ph level ie to keep development going?

[cliveh]

Hi, if I wanted to make a film developer with 1g metol per litre, how much is enough sod. Sulfite to maintain a borax like ph level ie to keep development going?

Why would you want to do that?

[john_s]

Hi, if I wanted to make a film developer with 1g metol per litre, how much is enough sod. Sulfite to maintain a borax like ph level ie to keep development going?

You can make D-23. No amount of sulfite will match a borax-like pH.

[nworth]

D-23 is often used at a 1+3 dilution - a bit less than 2 g/l of metol. You could go with 15g of sulfite, but I would suggest (for no really scientific reason) sticking with about 25 g.

[Gerald C Koch]

I would suggest the Beutler formula. The working solution contains 1 g of Metol, 5 g of sodium sulfite, and 5 g of anhydrous sodium carbonate per liter. Only 1 g of Metol may not develop the film completely at the low pH created using sodium sulfite alone as the activator. Remember that Metol is an acidic salt.

[el wacho]

thanks everybody for your responses. my intent was to get a little finer grain than beutler's. the 1g metol stipulation was just a bench mark. after reading your responses and thinking about it a bit i see that if i want to keep it at 1g/L i'll need the borax or experiment with dilutions of D23. are there any other alternatives to borax (within that ph range) that are unbuffered? thanks again.

[Relayer]

are there any other alternatives to borax (within that ph range) that are unbuffered?

buffer capacity of solution depended from borax (or other alkali) concentration. i.e. 1g/l borax is less buffered than 10g/l borax.
you can try baking soda NaHCO3 which give pH~=8.1, or mix it with Sodium Carbonate Na2CO3 for giving any pH in range 8..10.5, depended from proportion NaHCO3 and Na2CO3
some other alkali with pH range
Sodium Citrate - 8.5
Na2HPO4 - 9
TEA - 9.6

[el wacho]

thanks Relayer.

[litody]

the following is said to be the old formula for Perceptol but I have no concrete proof of this.

Sodium Tripolyphosphate 3.5 gms # buffer not required with pure water.
Metol 5.0 gms
Sodium Sulphite anhyd.100.0 gms
Sodium Chloride 30.0 gms
water to 1 Litre

use as stock, 1+1, 1+2 or 1+3.

At 1+2 you would have 600ml of working strength using 1gm of metol.

[el wacho]

found this which is relevant. d23 at 1:7