D-76: full strength or 1:1?

wclark5179 · Jul 26, 2010

"Now I'm confused."
"What do you think?"

Join the crowd Ralph, my friend!

1:3 means to me 1 part stock to 3 parts water to make working solution. Therefore, 4 ounces of stock times three parts water (12 ounces of H2O) equals 16 ounces of working solution, 4 plus 12.

However, with WD2D+ It's 1 to 50. As per the instructions, I start out with 500 cc's of water and add 10 cc of A and 10 cc of B. Then I end up with 520 cc's of stock.

Have I got it correct? Go figure & smiles!

swchris · Jul 26, 2010

RalphLambrecht said:
I agree, but what would you mix if Kodak is asking for 1:3? I would make it 1/3 stock and the rest water. In other words, 1+4.

I think 1/3 stock and the rest water is 1+2, isn't it?

RalphLambrecht · Jul 26, 2010

swchris said:
I think 1/3 stock and the rest water is 1+2, isn't it?

You are paying attention! Yes, you're right. I took the liberty to correct it.

Anyway, I prefer the 1+x notation too, because it easier to follow in my opinion. Of course, it doesn't really matter as long as it is understood, but I bet that Kodak's instructions are interpreted in two different ways, and I doubt that Ilford has this problem.

jp498 · Jul 26, 2010

1:1 happens to be equal to 1+1.

The + is easier to scale to specific quantities. Just multiply it to get to the quantities needed, like (1+3)*250 = (250ml + 750ml) for 1000ml. The end volume and ingredient volume is more important than the actual number of the ratio for practical purposes.

1/3 isn't quite right as a substitute for 1:3, 1+3 is actually 1/4 and 3/4 instead of thirds.

dancqu · Jul 26, 2010

Discipline

Chemistry is the discipline. The correct
notation is ' : '. A ratio is indicated. For
example parts A to parts B. Dan

Keith Tapscott. · Jul 27, 2010

RalphLambrecht said:
Back to the title of this thread. What does 1:1 mean?

I see that some folks write dilutions as 1:1 vs 1+1 for example. I know, people mean the same concentration with both descriptions, but is it?

Let's take another example:

1:3 is what?
1/3 strength or 1 part stock solution + 3 parts water?

When referring to a drawing scale 1:1 means full size. Does it also mean full strength or is it a 50/50 solution, and therefore, 1+1, because that's what we mean when we use it, right?

Confused? Then just look at that:

Kodak uses 1:3, Ilford 1+3 and so does the Film Developing Cookbook and The Massive Development Chart.

Now I'm confused.

What do you think?

I interpret 1:3 as being 1 part stock diluted with 3 parts of water.

Alex1994 · Jul 27, 2010

I've used it stock with FP4+ and got really fine grain and good tonality. I guess it doesn't make a massive difference stock or 1+1. Kodak says that 1+1 has slightly higher acutance but slightly coarser grain.

paulfish4570 · Jul 27, 2010

Ran my first roll of Arista Premium 400 1+1 last night. Negs look fine, but I will not be able to compare with straight stock until I replace my scanner ...

RalphLambrecht · Jul 27, 2010

dancqu said:
Chemistry is the discipline. The correct
notation is ' : '. A ratio is indicated. For
example parts A to parts B. Dan

Dan

Thanks for trying to help. You say a ratio is indicated. 1/3 is a ratio. What does 1:3 mean; 1/3 (because of ratio) or 1+3?

RalphLambrecht · Jul 27, 2010

Keith Tapscott. said:
I interpret 1:3 as being 1 part stock diluted with 3 parts of water.

I have too, but I also found out that not everyone does.

djhopscotch · Jul 27, 2010

From course work in chemistry, ":" was used to mean "of" 1:3 would be 1 part chemistry a total solution of 3 parts, or 1/3. 1:1 would be a nonsense statement since you are saying "1 of 1". Not sure how photography moved away from the chemistry world in this regard.

Keith Tapscott. · Jul 27, 2010

RalphLambrecht said:
I have too, but I also found out that not everyone does.

Which is why Kodak should replace the : with a + to stop this confusion.

mike c · Jul 27, 2010

djhopscotch said:
From course work in chemistry, ":" was used to mean "of" 1:3 would be 1 part chemistry a total solution of 3 parts, or 1/3. 1:1 would be a nonsense statement since you are saying "1 of 1". Not sure how photography moved away from the chemistry world in this regard.

I'm a little confused,all ways thought that 1:3 meant 1 part solution to 3parts water (4 prts total) am I wrong.:confused:Have no chemistry background.
Mike

RalphLambrecht · Jul 27, 2010

mike c said:
I'm a little confused,all ways thought that 1:3 meant 1 part solution to 3parts water (4 prts total) I'm I wrong.:confused:Have no chemistry background.
Mike

I don't think there is a right or wrong; just a common understanding. Trouble is, this one might not be all that common.

mike c · Jul 27, 2010

RalphLambrecht said:
I don't think there is a right or wrong; just a common understanding. Trouble is, this one might not be all that common.

Well I've done ok so far with regular developers so far,but starting to use alternate processes and was a little concerned as they are not all ready mixed chemical packs.Ratio's or Parts that is the question.

Mike

fschifano · Jul 27, 2010

Putting this thread back on track... I like to use D-76 diluted 1+1 for reasons of economy and consistency with most everything. The differences in working properties between full strength and diluted D-76 are very subtle, and result in no meaningful change in the look of the prints for me. Using D-76 straight as a one shot developer is wasteful, and re-using t without replenishment means calculating new development times as the developer exhausts. If I ran enough film to make a replenished system feasible, I'd consider doing so; but I'd also consider using XTOL for the job since it requires no special replenisher. The stock developer is its own replenisher.

RalphLambrecht · Jul 28, 2010

Frank

Sorry for hijacking the thread, but I thought it was done.
Your last post is a nice summary and has no open question. How would you like this thread to continue?

Andrew Horodysky · Jul 28, 2010

fschifano said:
Putting this thread back on track... I like to use D-76 diluted 1+1 for reasons of economy and consistency with most everything. The differences in working properties between full strength and diluted D-76 are very subtle, and result in no meaningful change in the look of the prints for me. Using D-76 straight as a one shot developer is wasteful, and re-using t without replenishment means calculating new development times as the developer exhausts. If I ran enough film to make a replenished system feasible, I'd consider doing so; but I'd also consider using XTOL for the job since it requires no special replenisher. The stock developer is its own replenisher.

When I used D76, I too, found little difference between the stock developer and 1:1 dilution. I ended up developing all my 35mm film 1:1 at 68 degrees F. D76 is a great all-round developer. Today, I use XTOL 1:1.

stevebrot · Jul 28, 2010

One caution regarding higher dilutions of any developer beyond manufacturers recommendations. You should always make sure that there is adequate chemical (developer strength) present to fully develop the image. This requires using larger volume of dilute developer than might normally be used.

Example:

1:1 D-76 for small tank 35mm film requires 8oz stock + 8oz water to fill the tank
1:3 D-76 for the same 35mm roll requires 8oz stock + 24 oz water for a total of 32 ounces
All 32 ounces need to be used in a larger tank to avoid exhaustion, regardless of development time and agitation

This is a common issue with higher dilutions of HC-110 and is discussed by Ansel Adams in The Negative (Chapter 10) and on various sources on the Web.

Steve

fschifano · Jul 28, 2010

I'm pretty sure that's why Kodak stopped recommending XTOL 1+3. It does work well at that dilution, but you do need a large tank to pull it off. I'll bet too many people were trying to do it in an 8 or 16 ounce tank, then claiming XTOL was faulty, thus giving the product a bad rep that still persists.

RalphLambrecht · Jul 28, 2010

fschifano said:
I'm pretty sure that's why Kodak stopped recommending XTOL 1+3. It does work well at that dilution, but you do need a large tank to pull it off. I'll bet too many people were trying to do it in an 8 or 16 ounce tank, then claiming XTOL was faulty, thus giving the product a bad rep that still persists.

Frank

There is a lot more to that story, but we will stick to the subject of this thread.

dancqu · Jul 28, 2010

Stick With the Discipline

RalphLambrecht said:
Thanks for trying to help. You say a ratio is indicated.
1/3 is a ratio. What does 1:3 mean; 1/3 (because of ratio)
or 1+3?

The colon does indicate a ratio. In our case an expression
which includes the the colon indicates the number of units
of each material to be included in the final mixture. For
example 1:3; 1 unit of A to 3 units of B. That is the
combining ratio of two components. The units
may be of any dimension.

Expressing a ratio as a fraction only introduces
a confusion in our nomenclature. So too the
sign for addition. Remain disciplined. Dan

clayne · Jul 29, 2010

RalphLambrecht said:
I have too, but I also found out that not everyone does.

It's only people trying to shoehorn generic chemlab mindset onto something that everyone else absolutely already understands as parts to WATER. As someone wisely mentioned earlier: context is everything.

RalphLambrecht · Jul 29, 2010

dancqu said:
... Remain disciplined. Dan

I am. I stick to 1+x!

RalphLambrecht · Jul 29, 2010

clayne said:
It's only people trying to shoehorn generic chemlab mindset onto something that everyone else absolutely already understands as parts to WATER. As someone wisely mentioned earlier: context is everything.

Whenever two systems exist to do an identical thing, confusion is pre-programmed. Context is important but consistency is key.

D-76: full strength or 1:1?

Andrew Horodysky

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