hypo and sodium sulfite fixer issue

[steve hartsfield]

I have made 2 batches of of "plain" hypo fixer for my toning process that has gotten milky/cloudy after fixing approximately 50 8x10 prints. I am using some old Zone VI hypo (anhydrous I assume since it is 673 grams for making a gallon). To that hypo, I add 120 grams of sodium sulfite. It is hot in the south and my fixing bath was 77 degrees, if that has anything to do with it.

In my printing process, I use fixer 24 at 4 minutes, then wash and dry the prints for toning later. When I tone, I re-fix in the hypo-sodium sulfite solution, then selenium tone. I cannot understand why there is a slight milkiness after 50 8x10s (the life should be around 100), there shouldn't be in my opinion. Maybe the plastic bagged sodium thiosulfate age has something to do with it, but it has been kept in the refrigerator and it is dry and powdery when I mix it.

Just to see, I put 2 drops of hypo check solution into 2 ounces and no precipitate formed. I discarded the first batch that got milky (matter of fact, I have never before had fixer get cloudy on me), wondering what's going on here.

[Michael R]

It is hard to diagnose, but is there anything different in your mixing process for the hypo/sulfite solution than before? Different water? I'm asking because depending on water content, an alkaline solution of sodium sulfite can cause the precipitation of calcium sulfite.

[Jim Galli]

Sounds like something I would ignore and just keep working. But, such is the temperament I'm blessed with.

[Ginette]

Is it too much sodium sulfite? Is it from a standard receipe?
If I compare to TF-2, for 1 liter:
Sodium thio penta 250g (158gr anhy)
Sodium sulfite anhydrous 15g
Sodium Metaborate 10g
Capacity is 20 8x10 per liter.

[LabRat]

Are you using tap water for mixing??? Sometimes during the summer, your water utility might "spike" the chlorine content if there is a microbe/bacteria/algae bloom... You might be able to tell by filling a clear container with a rapid blast from the tap, and watch the foaming while the water settles... If it stays bubbly/milky/fizzy after a moment, (and might have a slight chlorine smell) it's "spiked"... I have seen it where solutions with large amounts of dissolved chem. were mixed with "spiked" water, and the chlorine reacted with everything, causing milkiness, or even precipitation of the dissolved solids... (Or call your local utility and ask...) Another way to tell is if you use a water filter and the filter cartridge is too fine, the water will come out milky and fizzy, probably because too fine of a filter seems to "knock" the chlorine out of solution...

As have been mentioned, check the formula again, and cross check it with another version of the formula (for errors)... Also, I have tried making concentrated stock solutions of different fixers in the past, and if there is too much dissolved chem. in the solutions, there is a point where these will "fall out" of the solutions, and settle to the bottom of the container, and have a "rotten egg" sulfur smell... (The amounts you are using seem like it might be close to the "saturation" point...) If you let it decant for about a week (in a bottle you can see through), you might see the solution upper level clear, and solids on the bottom...

See if your present batch is still "fixing" by putting a strip of undeveloped film in it and note the time it takes to clear the film... If you mix a new batch, use bottled or distilled water now if there might be a utility problem... And sniff the old batch for (a slight) sulfur/chlorine odor...

Steve K

[Michael R]

It looks like OP is mixing these as weights per gallon.

[Ginette]

It looks like OP is mixing these as weights per gallon.

Yes but even in gallon, 4x15g= 60g, he used the double.

[steve hartsfield]

It is hard to diagnose, but is there anything different in your mixing process for the hypo/sulfite solution than before? Different water? I'm asking because depending on water content, an alkaline solution of sodium sulfite can cause the precipitation of calcium sulfite.

[steve hartsfield]

Yes, I did, and always, use tap water. And yes, it is high in calcium and chlorine. Hmmmm, fixer 24 never did this, maybe because of the sodium bisulfite?

[steve hartsfield]

I went by Ansel's "formula" in The Print, he suggested for a gallon of "plain" hypo fixer, 2 lbs. of thiosulfate and 4 ounces of sodium sulfite (113.39 grams). I just used 120 grams sodium sulfite.

[LabRat]

Sodium sulfite or bisulfite??? You would be using Sodium sulfite, as bisulfite is slightly acetic, and mainly used for tweaking the pH, to put a solution in a different working range...

Steve K

[steve hartsfield]

Penta thio for a gallon would be 960 grams (roughly 4 x 250g), and 4 (I will equate liters to quarts here) liters x 15g = 60 grams sodium sulfite per gallon by that recipe. However, I could certainly cut back on the sodium sulfite. Maybe see what effects are at 100 or 60 grams per gallon.

[steve hartsfield]

Labrat, I don't put bisulfite in the toning process fixer, I was referring to it being used in fixer 24 and maybe that is why I don't get the cloudy fixer.

[Ginette]

Yes you correct your calculation 4x15=60!

[steve hartsfield]

Ok, I appreciate the input. I am going to continue to use my current "toning" fixer for another 50 equivalent 8x10s, toss it, and make the next batch with 60 grams sodium sulfite for the gallon with Distilled Water! I'll see what happens. If my present fixer gets more cloudy, I will toss it before continuing. BTW, there is no sulfur/rotten egg smell. Greatly appreciate the input guys!

[Bruce Barlow]

At the risk of being incendiary, I quit using pure Hypo for toning, and just use TF-4 before fixing, born out of necessity once, long ago, when I had no hypo. As I recall, the issue was supposed to be staining, but several hundred prints later, I have never stained one.

If they're not archival, well, I'm not sure they deserve to outlive me anyway. And they all look good stored in the boxes so far.

My 2 cents.

[Michael R]

Ok, I appreciate the input. I am going to continue to use my current "toning" fixer for another 50 equivalent 8x10s, toss it, and make the next batch with 60 grams sodium sulfite for the gallon with Distilled Water! I'll see what happens. If my present fixer gets more cloudy, I will toss it before continuing. BTW, there is no sulfur/rotten egg smell. Greatly appreciate the input guys!

Distilled water is a good idea, or you can add a calcium sequestering agent, or you can lower the pH a little with a small amount of bisulfite/metabisulfite (something like 5-10g bisulfite per 100g sulfite).

The reason calcium sulfite is not precipitated from Fixer 24 is that it is mildly acidic (whereas your hypo+sulfite formula is fairly alkaline).

By the way this is one reason why most commercial hypo clearing agent formulas aren't just plain sulfite. In addition to sequestering agents, they are typically formulated to be roughly neutral or slightly alkaline in pH.

The sulfur smell from fixers comes from sulfurization, which happens under more strongly acidic conditions.

Chlorine spikes in tap water would be a different matter. In that case I would simply avoid using tap water for mixing chemicals. Keep it simple with distilled/deionized water.

[AtlantaTerry]

When going to the grocery store to buy distilled water, I make sure the label says "Steam Distilled".