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mabelsound
05-02-2008, 13:23
I got my chemicals and supplies today, and mixed up 500ml each of stop bath and fixer & put 'em in brown glass bottles. The instructions are pretty straightforward for those.

But D76 is another story. I gather from my online investigations that most people mix up a batch (either full strength or 1:1) from powder for each use. Correct? Because diluted D76 doesn't last very long.

The only instuctions on the bag, however, are to dump the whole thing into a gallon of water.

So if I want to make 500ml at a time (that's the size of my tank), how much powder do I use?

sienarot
05-02-2008, 13:41
With D-76 (and probably most, if not all, powder developers), you should be mixing the whole package as stock and diluting what you need afterwards.

mabelsound
05-02-2008, 13:59
Hmm. I don't have a collapsible container...will it keep for a while, in the dark, in an opaque one-gallon container? because I DO have one of those.

I bought a couple gallons of Rodinal on eBay but they haven't come yet...

pau3
05-02-2008, 14:02
If the tank is not collapsible, stock solution will last for two months. If you have
a gallon, you must go and shoot!
Pau

Anupam
05-02-2008, 14:39
The only instuctions on the bag, however, are to dump the whole thing into a gallon of water.

No. Dissolve the powder in a little less than a gallon of water and then add more water to bring the total up to a gallon.

Store the stock solution in full soda bottles with no air in a dark cabinet and they should last a while. You will know they've gone bad if they start turning brownish. Plastic soda bottles are great because they are made to keep pressurized air in (or out in this case) and come in a variety of sizes and are easy to replace every once in a while when they go dirty. Drink some coke!

Ducky
05-02-2008, 17:21
I mix my D-76 to stock a gallon at a time and store it in two half gallon clear plastic bottles. One is full to the top and closed tight. The other gets first use. I keep everything in a cardboard box in a dark cabinet.

charjohncarter
05-02-2008, 17:36
For us metric people, is there a smaller powder to water formula? Say to make a liter of stock or 1:1. So you are almost using it one shot. I use use two other developers, and I would be throwing out more than I use with the Kodak D-76 method.

mabelsound
05-02-2008, 17:39
For us metric people, is there a smaller powder to water formula? Say to make a liter of stock or 1:1. So you are almost using it one shot. I use use two other developers, and I would be throwing out more than I use with the Kodak D-76 method.

Right. Personally, I would prefer to make it one 500ml amount at a time. I only got D76 because it's the only developer B&W seemed to be willing to ship, and I'd already spent half an hour putting together all my other supplies on their site...

crawdiddy
05-02-2008, 17:57
Btw, I have mixed half or quarter batches of D-76 at a time, leaving the remainder for later in powder form. To start off, I carefully measured the dry D-76 powder, and then just used half (or a quarter).

Then, I store the unused powder in double zip-loc bags, with as much air expelled as possible. I have had good luck with this procedure, although when you go back to reuse the powder, if it looks significantly brown, I throw it away.

I know this procedure isn't necessarily recommended. Because the powder may not have all compounds evenly distributed. Nevertheless, it has worked for me.

charjohncarter
05-02-2008, 19:03
Thanks mabelsound and crawdiddy, I guess if you open the powder it starts downhill. Maybe I'll get one of those vacuum packers they sell on Saturday afternoon on TV.

BillBingham2
05-02-2008, 19:04
I used quart bottles to store any developer, filling them as close to the top as possible. I even tried floating some plastic wrap on the top to keep the air away. Dark and cool I had it last for a few months as I remember. This also was in brown glass bottles which I think are harder to come by these days.

B2 (;->

steamer
05-02-2008, 19:14
I've got some plastic accordion containers that can be compressed as you use the developer. I've heard some folks add marbles to top up their bottles. Whatever you do don't mix it 1:1, it has a life of about a few hours.

feenej
05-02-2008, 19:22
I always measure out half the powder and mix a half batch. I was thinking about going to quarter since the last D76 I made went bad after I used it only two or three times, after about a month.

40oz
05-03-2008, 08:23
If one wants a half-liter of D-76, one mixes the whole package and only uses a half liter :)

You can buy D-76 in liter mix packages. I wouldn't worry about how much you discard, as even a gallon package is $5-6 where I live. If you throw out half of it, you still only spent at most $6 on developer. Buy the liter packages if that is still an issue for you.

FWIW, as I understand it D-76 degrades via oxidation. So if you split the bottles after mixing into small sealed constainers filled to overflowing, that shouldn't be a big issue. In addition, I've got many more months out of a gallon of D-76 simply by using a bottle designed for chemical storage vs. "any old plastic bottle." D-76 will last much longer than two months properly stored, even in a gallon container you are pouring out of as you use it. One certainly doesn't need an accordion bottle for that.

mabelsound
05-03-2008, 08:37
Well, I got one of those opaque gallon containers from B&H, so presumably it'll work OK...

bsdunek
05-03-2008, 17:38
I bought 4 oz. glass bottles at the drug store. After mixing the one gallon, and letting it sit at least 24 hours, I divide it up into the 4 oz. bottles. I use this diluted 1:1 which gives me 8 oz. for a single roll of 35, etc. Works for me, and my D-76, Acufine, etc. last at least six months.

MartinP
05-06-2008, 09:56
I would second the suggestions for dividing up your developer solution amongst smaller bottles, in order to reduce oxidation of the stock. D76 is available in Quart packs too so perhaps that might help you. I would also suggest boiling the water you use to make up the stock - obviously let it cool before using the water. Heating the water drives out most of the gasses dissolved in it, including the oxygen which we are worried about.

You can actually place an iron nail in a (sealed) container of boiled water for weeks with no sign of rust. It is a favourite "children's science" experiment, try it in case you want some proof !

SolaresLarrave
05-06-2008, 10:06
I switched from D-76 to T-Max, which comes in concentrate form and only gets diluted 1:4 when you're going to use it. It has a longer shelf life and, to me, it's easier to use.

D-76, however, is a good one to learn with, because most films have a setting for it.

BTW, before mixing it, some people suggest boiling the water, letting it rest overnight, heat it up again and mix it then. I simply use Brita-filtered water, heat it to the mixing temperature and then mix the powder in stages in a large bucket. Afterwards, it gets stored in a brown, plastic "accordion" bottle. It may last for a while... up to four months.

But I hate mixing it, so I prefer T-Max.

Have fun! :)