D-76 brownish 24 hours after mixing

traveler_101

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D-76 users . . . just a curiosity, because it didn't present a problem . . .

Yesterday I mixed a litter size package of D-76 and left it overnight. When I went to develop today the liquid was brownish in colour . . . though I suppose it would better be described as a very light transparent tan.

Alarmed because I had read that D-76 goes bad when brownish in colour, I checked its strength with a strip of film and went on the develop my roll. No problems . . .

I am just curious because I never had this happen before, even after mixed D-76 sits around for 3-4 months; it is always clear using the same water supply. Here are some particulars that seemed absolutely correct:

1. the package was within its stamped date for safe use

2. the powder was white, not discoloured

3. It mixed up nice and clear with 100% dissolution--nothing floating

Here are some particulars that might localise an issue:

4. I boiled the water and then let it cool before mixing, but it may have been too warm, i.e. exceeded recommended temperature (?)

5. After mixing it sat in a plastic gallon jug until this morning (as usual; I distribute it to brown glass bottles if it is not used within 3-4 days)

Any ideas what it's all about?
 
I wouldn't recommend to use boiling/just boiled water (I heat the water until I hear it outgassing, not more, and this is plenty hot enough to quickly and fully dissolve the D76 powder) but IMO this isn't what caused the problem.

Could your tap water having been brown by itself yesterday, due to some work on the water distribution network in you area ?

Reminds me the "brown water" the character played by Woody Allen in "Manhattan" has to face once he's set up in his new apartment... ;)
 
I remember seeing this a couple of times before, and everything worked out fine, so I never investigated it further. The stuff around the cap was more viscous and brown. Maybe a loose cap and oxygen reacted with the D-76?
 
Fresh D76 has a slight color.

Heat to 125 deg F, no more or you will oxidize the chemicals.

It should not have been left in an open container overnight. Keep air away from it even if you lay a GOOD GRADE of food wrap over the surface.

If you mix from scratch as I do, put a pinch of sodium sulfite in first and it will keep the metol from oxidizing. A pinch is what you can hold between your fingers. Too much an metol will not dissolve.

A slight color is ok. Tea color is gone.
 
Odds are oxidation.

Plastic and developer are not friends. Glass bottles are good. Dark glass bottles are best.

As it's not easy to displace the oxygen from bottles I used to have a couple of medium sized ones that I topped off them off for medium term storage.

Try pharmacies for glass bottles, used to be the best place but not sure they have too many of them any more.

B2
 
Thanks for the responses.

Well for one thing, I didn't leave it in an open container. I put it in my brown plastic jug bought at B&H; the cap was securely fastened. It only sat over night, but I needn't have stored it in there at all. I have a collection of dark glass wine bottles; the bottles have the screw type caps and I seal them with a piece plastic wrap. In February I made a gallon of D-76 for the first time, stored them in the bottles and I was able to use all of it over 5 months. There was no spoilage, no discolouration at all. After that experience I decided not to buy anymore litre packages of D-76.

The only thing I did differently this time is over-heating the water. If Ronald is right about oxidising the chemicals with water over 125F then that could be the problem right there. Also there is no reason to store in a plastic jug even over night when I have glass bottles.
 
Kodak say you are OK to heat up to 131F. I have noticed a few problems with D76 lately becoming cloudy...leading to white spots on negs. Perhaps the Kodak QC is not as good as it once was?
 
Benzoquinone is the oxidation product of hydroquinone. it is brown. Freshly mixed D76 has a slight colour; some oxidation cannot be avoided.

Marty
 
Odds are oxidation.

Plastic and developer are not friends. Glass bottles are good. Dark glass bottles are best.

As it's not easy to displace the oxygen from bottles I used to have a couple of medium sized ones that I topped off them off for medium term storage.

Try pharmacies for glass bottles, used to be the best place but not sure they have too many of them any more.

B2
+1

I have been using glass bottles (dark glass) for decades and never had any problem whatsoever. Plus, this is the only stuff you can keep very clean on the long run. I have a friend who works in a laboratory so I got several nice dark brown glass bottles from there for free (would have been tossed away). But, yes, you can get some from a pharmacy.

Or : beer glass bottles. You drink the (good, if possible) beer and then you're done. I use some Fisher brown bottles to store my wet printing chemicals.

Last week I developed a roll of Delta 3200 in some Microphen I had been storing in a small glass bottle for one year and a half. There was just enough of it in the bottle to develop that 120 roll at 1+1. Everything went out perfect.

Of course : dark glass bottles are the best, but you also must store them in a cool, totally dark place.

My guess is that plastic may be porous - that is, there is some oxydization of the fluid caused by oxygen getting through the plastic - the only air tight areas of plastic bottles would be their caps lids.
 
You should boil the water, then let it cool down to the correct temperature before mixing it w/ the powder. Don't heat the powder and water together. By boiling the water you will allow it to out gas oxygen (which is possibly why yours turned brown). It needs to sit 24 hours after mixing for the PH to settle down, and it should sit tightly capped. I mix mine on the stove in a big plastic bucket w/ a bandana over my nose and mouth and the vent fan on. It would be simpler to just take it outside though.

I'm amazed you ever got 3-4 months from D76. Mine goes "off" in just 3 weeks, but it gets pretty hot in our Florida home. By "off" I don't mean it is unuseable, but the PH gets active (well documented w/ D76, going back 70 years or so) and I get somewhat different and grainier results than the first 2-3 weeks. Which is why I switched to TD-16. My Tri-X negs look essentially identical to those developed in D76, and the stock solution will keep up to 6 months if tightly capped w/ no air space in the top of the bottle. I like consistent results.
 
You should boil the water, then let it cool down to the correct temperature before mixing it w/ the powder. [skip] By boiling the water you will allow it to out gas oxygen (which is probably why yours turned brown).
There seems to be something illogical in this : you recommend to use boiled then cooled down water, then you say that the oxygen outgassing during the boiling phase is what caused the D76 stock solution to become brown...
 
Plastic and developer are not friends. Glass bottles are good. Dark glass bottles are best.

B2

Is there anything wrong with the plastic bottles companies sell that are meant for photo chemicals? Also is there any harm in reusing the plastic bottles the chemicals came in, i.e., empty TMax bottle?
 
Another option for dark bottles might be wine bottles.

Folks who ship expensive fountain pen inks do so in glass bottles. Why? Shelf life. My son got a broken bottle (order it in the winter, cracked in transit), salvaged a bit and put it into a plastic bottle. Put the bottle in a stainless steel mixing bowl and a few days later the ink had leaked through the bottle.

Some plastics might work (e.g. PVC) for medium term storage (a month or two) but my father who was a photographer for Kodak and ran his own B&W lab for over 30 years always used glass. Developer, paper and film were basically free for him but still used glass.
 
My challenge with wine is how oxygen will quickly get into the bottle, usually through the opening on top, and the wine goes bad after a few days. Haven't found an easy and inexpensive way to prevent that. Boxed wine stays fresh much longer but has had a history for value wines and the industry has used glass with cork for a long time. Even the artifical cork that many winerys use still don't adequately re-seal once the bottle is opened.

Just my experiences.
 
My challenge with wine is how oxygen will quickly get into the bottle, usually through the opening on top, and the wine goes bad after a few days. Haven't found an easy and inexpensive way to prevent that.

Buy wine with screw caps! It took me a while to get over the personal stigma of buying non-cork wine (a bit the same as getting use to buying beer in cans) but screw-cap wine isn't necessarily bad wine.
 
Buy wine with screw caps! It took me a while to get over the personal stigma of buying non-cork wine (a bit the same as getting use to buying beer in cans) but screw-cap wine isn't necessarily bad wine.

Good idea!

Thanks.
 
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