D-76 question??

After I prepare D76/ID11 stock solution, I fill it in 150 ml glasses to the rim and seal them. You could add a drop when I'm done with them. I saved a few olive glasses for this purpose. Once, I forgot one of these once at the back of my developer shelve for almost a year (they are dated), and it was perfect. No increase in activity, which is otherwise common with aging D76.

 

I have a Kalt data bottle which I squeese most of the air out of, but no where near to Ralph's standards. It's been going on about 2.5 years now, with fairly light use... still going strong.

 

The rule of thumb (per Kodak) is six months in full bottles. It's half that, if I recall correctly, for partially full bottles but the emptier the bottle, the shorter the life.

If you don't use a lot, you might want to consider buying the bulk ingredients to make your own D-76. It's not that hard, and then you can make as little or as much D-76 as you like, still getting economies of scale by buying reasonable quantities of the raw ingredients, which keep for years.

 

For me - three months or more, in a half-filled bottle. Mine is stored in a fairly dark place [if that matters, I don't know]. You should be fine.

 

IIRC, the package claims that a gallon will last 6 months in a full bottle and 2 months for a half-full bottle.

 

It starts to change slowly after 6 months. I have made batches ans stored in full glass bottles and tested periodically with a test target, same camera, electronic flash, same batch of film etc. Tests were weekly at first, then every two weeks, then monthly for the last two or three.

Kodak is right, 6 months.

What is wrong is 6 weeks in a half full glass bottle. I get 1/2 grade in contrast after just one week. I will never use D76 from a half full bottle again. It is made and stored in 125 ml bottles, enough for one film at 1:1. Two bottles if I use stock. I mix from raw chems around a liter at a time and toss it after 6 months.

 

You could always use an inert gas (Tetenal produce some such called Protectan) to reduce oxidisation. I've always used lighter fuel gas - butane, instead. Works well enough for me.

 

If its still pretty clear it should be perfectly fine. D76 gets darker and darker at it goes "bad". On poster a while back claimed he had a bottle of D76 that all the air had been removed. He said it was a year old but still clear. He tried it, it worked fine. I think he did add a little extra time to it. So would not do it on important film.

Jason