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Raffay
5-Dec-2013, 08:10
Hello All,

I am planing to mix D76 for the first time, the packet says mix in 3.8 litres of water. I want to know if after heating the water can I put it in an open bucket and then pour the powder and mix, or am I supposed to mix it in a container with a closed lid. As finding a container with a cap that can hold 3.8 L is going to be very difficult.

Cheers

Raffay

vinny
5-Dec-2013, 08:25
I'm pretty sure the picture on the bag shows an open container.........

Jan Pedersen
5-Dec-2013, 08:28
You can mix in an open bucket no problem. It is best to start with less than the full amount of water as the chemistry will add volume.
Start with 3 liter of water and dissolve the chemistry and then add water till you have 3.8L
I would highly recomend that you filter the developer before you put it in your clean storage bottles.

Raffay
5-Dec-2013, 08:30
So you mean that the mixed chemical should be 3.8 L and not add chemical to 3.8L of water. Secondly, any easy way to filter the chemical.

Thank you, Raffay.

Jan Pedersen
5-Dec-2013, 08:34
Yes, you want a final 3.8L when all is mixed.
I use coffee filters in a funnel when i fill my glass bottles.
Not filtering will cause you a lot of grief when it is time to print. Everything you can do to keep dust and other small stuff in your developer away from your negatives will make life easier in the darkroom.

Raffay
5-Dec-2013, 08:35
Thank you for your valuable input.

AtlantaTerry
5-Dec-2013, 11:54
Never ever never ever mix powdered chemicals anywhere near where you will later hang wet negatives to dry. Never.

If you must, do the mixing outdoors.

Otherwise you will have chemical dust out there just drifting around waiting for you to hang to dry The Best Negative You Ever Created In Your Life so that little bugger can land on the wet emulsion, dig in and explode it's little package of nasty chemisty all over your precious.

Jac@stafford.net
5-Dec-2013, 12:57
I hope it is clear that mixing chemistry in a common metal bucket is a bad idea.

Heroique
5-Dec-2013, 14:52
I hope it is clear that mixing chemistry in a common metal bucket is a bad idea.

Blackberry picking before mixing is bad for the solution.

Blackberry picking after mixing is bad for the fruit.

Separate buckets is a good idea!

Leigh
5-Dec-2013, 14:54
The only metal containers that can be used with photographic chemicals are made of stainless steel, specifically designed for use with photo chemistry.

Don't use any other kind of metal container for any purpose in the darkroom, except mopping the floor. :D

- Leigh

Jim Noel
5-Dec-2013, 15:59
You are supposed to mope the floor?

BradS
5-Dec-2013, 16:04
Never ever never ever mix powdered chemicals anywhere near where you will later hang wet negatives to dry. Never..


Not sure if you're serious or joking around. I'v been developing film on the same kitchen counter where I mixed up the developer (often just a few minutes prior) for over twenty years...never noticed any issues related to chemical dust. My mom did the same thing...for a long, long time...I think you must be joking. :)

Jim C.
5-Dec-2013, 17:25
Either he's joking or is very sloppy in pouring the powder. ;)
I also develop and hang wet neg and prints in the same area I mix chems, and never had a issue.


Not sure if you're serious or joking around. I'v been developing film on the same kitchen counter where I mixed up the developer (often just a few minutes prior) for over twenty years...never noticed any issues related to chemical dust. My mom did the same thing...for a long, long time...I think you must be joking. :)

Raffay
5-Dec-2013, 19:12
So I am supposed to mix the chemicals in a plastic bucket? That's the only thing available here, and please don't tell me to get a bucket that is made for chemical mixing :)

Cheers

Raffay

Tim Meisburger
5-Dec-2013, 19:33
Yes Raffay, that is fine. Just buy a cheap to use for that.

Jan Pedersen
5-Dec-2013, 20:41
Raffay, just remember to filter your developer before you put it in your storage bottles and you will be rewarded. :)

As an afterthought, also use filtered water to clean your storage bottles to eliminate any chance of particles on your valuable negatives.

tgtaylor
5-Dec-2013, 21:09
Although I haven't mixed D-76 in some time, the instructions on the package should be self explanatory p probably to bring 3 lts of water up to a certain temperature and then slowly stir in the powder and continue stirring until completely dissolved. You can check on how much of the powder has been dissolved by shining a flashlight into it while stirring. If you see little white specs swirling around in the water keep stirring until you seen none. Then top the volume off to 3.8 ltrs (1 gallon). It's a good idea to let it to sit overnight before using.

I mix mine (Xtol) in a 2 gallon Arkay container with floating lid http://www.bhphotovideo.com/c/product/65732-REG/Arkay_603542_PRT_2FLC_Complete_Storage_Tank.html using a stirring paddle like this: http://www.bhphotovideo.com/c/product/999272-REG/dot_line_dl_6131_dlc_extra_long_stirring.html. A magnetic stirrer is on my shopping list.

Thomas

neil poulsen
5-Dec-2013, 21:24
You can mix in an open bucket no problem. It is best to start with less than the full amount of water as the chemistry will add volume.
Start with 3 liter of water and dissolve the chemistry and then add water till you have 3.8L
I would highly recomend that you filter the developer before you put it in your clean storage bottles.

Thanks also for this advice. I just made up two gallons and will make sure that I filter it prior to use.

I use an automatic stirrer. But, there still can be some particles remaining.

As a comment, I note that 3.8 liters is 1.0039 gallons.

Jan Pedersen
5-Dec-2013, 21:46
1.0039 gallons will make the developer useless :)

Something I missed in my response to Raffay earlier is that it really does not matter if the end volume is 4L or 3L as long as he will test and end up with perfect negatives.
Times given by Kodak will of course no longer be valid but the developer will still be as good but just in a different dilution as recommended by Kodak.
Consistency it really what is important. Test with the process that is convenient and stick with it.

Leigh
5-Dec-2013, 21:49
Hi Raffay,

There are many factors that influence how closely our actual environment is to "ideal".

For example, I have two completely separate sets of containers, measuring vessels, and implements.
One set is used exclusively for developers, and nothing else.
The second set is used for stop bath, fixer, and other auxiliary mixing duties.

It depends a lot on how much space you have.
My darkroom is about 3,5 meters square with lots of cabinets and shelves, so plenty of storage space.

- Leigh

Raffay
5-Dec-2013, 21:54
On another note, since I have to import D76 I want it to last for as long as possible. One advice I got was to store in smaller bottles and use one at a time keeping the rest secure, and would follow that. What I want to ask is that can I use stock for development, I have seen that ppl recommend 1:1 but in that case I will have to throw away after every use and all the chemical will be gone before I even know it.

Cheers

Raffay

Leigh
5-Dec-2013, 21:59
Hi Raffay,

Here's the Kodak datasheet on D76. It has a lot of information about using the developer, including full-strength, and has information about replenishment and storage:
http://www.kodak.com/global/en/professional/support/techPubs/j78/j78.pdf

- Leigh

Raffay
5-Dec-2013, 21:59
Thank you.

Jan Pedersen
5-Dec-2013, 22:04
I think it is possible to use D76 on a replenishment schedule as some does with Xtol. Do a search on Xtol and I think you will find some threads about replenishment.
If you do this you would need to make up two batches of D76. use of one batch full strength as your developer and add from the second batch when completed to add up to the volume you had before processing.

I do this with another developer Harvey's Panthermic 777 and it works very well.

The problem you run into is the expiration of the developer, it is hard to know when your developer has expired and no longer works as it did when you mixed it. Some developers as the 777 almost works forever and therefore is a lot easier to use in a replenishment schedule.

Ginette
6-Dec-2013, 00:49
Thanks also for this advice. I just made up two gallons and will make sure that I filter it prior to use.

I use an automatic stirrer. But, there still can be some particles remaining.

As a comment, I note that 3.8 liters is 1.0039 gallons.

I'm curious about the model you use for mixing large quantity. Many magnetic stirrers look to be for small beaker or maximum 2 liters.

Raffay
7-Dec-2013, 05:00
One more question, should i use battery water or bottled water will be good as well.

Leigh
7-Dec-2013, 08:10
One more question, should i use battery water or bottled water will be good as well.
I would recommend using distilled water for mixing the chemistry, and for the stop if you use a water stop rather than acid.

You can use tap water for the washes after fixing.

Photo processing can be sensitive to chemicals in the water, not just particles.

- Leigh

tgtaylor
7-Dec-2013, 08:30
Thanks also for this advice. I just made up two gallons and will make sure that I filter it prior to use.

I use an automatic stirrer. But, there still can be some particles remaining.

As a comment, I note that 3.8 liters is 1.0039 gallons.

Which is a good reason to let it sit overnight before using: Any particles not dissolved will settle to the bottom and will not flow out of the spigot as the inlet is positioned above the containers bottom. Filtering then is not only unnecessary but aerates the developer which shortens its life. From personal experience, Xtol stock will last 6 months when stored in a floating lid container.

As a note I have the Doran floating lid container http://www.bhphotovideo.com/c/product/43191-REG/Doran_PRPRT2_Chemical_Storage_Tank_2_Gallon.html and not the Arkay brand as I wrote above. I have two of these, one for film and the other for paper.

Thomas

Raffay
8-Dec-2013, 07:39
Finally mixed the chemicals, D76 was pretty easy. The fixer was a bit weird. Initially, foam was formed on the top slightly green in color but then layer when I mixed it the whole water became milky. After a lot of mixing I left it and when I checked later D76 was fine, but the container with fixer was clear water but at the base there was a white layer of powder. I am mixing it after every ten minutes, hope it is not ruined.

Cheers

Raffay

Raffay
8-Dec-2013, 21:17
The fixer is still not dissolved completely, there is a very thin layer of powder that keeps settling at the bottom. Will it dissolve now since the water is not hot any more.

Nathan Potter
9-Dec-2013, 12:11
The fixer concentration is not critical, so a small amount of undissolved chemistry is OK and can be filtered out if necessary. Alternatively you can heat the solution to a higher temperature to try and dissolve more of the residue but obviously the heating will need to be done in a non melting container such as stainless steel or pyrex glass.

A hotplate with a stirrer bar is very handy for mixing.

A comment on dry powder chemical dust. If you are a careful worker and take precautions in the way of minimizing dry powder dust in the air you can use the same space for drying negatives as for mixing powder. But it is clearly not the best situation for minimizing the risk of negative contamination. A well exhausted space is a far better option when possible. In my early bathroom setup I used a cardboard box with an exhaust fan and dryer hose vented thru the bathroom window.

Nate Potter, Austin TX., Chatham MA.