Embarrassing: Explain 1:1:100 to a dumb person

[GLS]

unless you're Kodak

Or a chemist.

If the two have indeed been used interchangeably by others in the past then such practice is nonsensical, UNLESS the "100" part in 1:1:100 is explicitly defined as "made up to 100 with water", " total parts of the mixture" or similar wording.

If the "100" part in this example is defined as pure water then no, the two conventions 1:1:100 and 1+1+98 are absolutely NOT the same.

 

[runswithsizzers]

Unless someone can point to some professional organization of chemists or some widely used chemisty text books that clearly define how to interpret the phrase "make a solution x:y" then it's pointless to say one side is right and the other side is wrong.

In post #56 of <this thread> Photrio member Dipositivo says it well:

"1:10 is a conventional notation, and as any conventional thing it has to be agreed among users to be of any meaning."​

That thread went on for 5 pages discussing this topic (dare I say arguing?), and add to that another 2 pages here. It's obvious that the users do not agree among themselves how to intrepret this notation, therefore assumptions are dangerous. The OPs question has been answered several times over because Sandy King is on record as saying mixing PyrocatHD should be mixed 1 parts each of A and B added to water at 1+1+100 (total volume 102).

It's interesting that photographers do agree how to intrepret the same x:y notation in macro photography. If I say a lens provides 1:1 magnification, everyone knows that means life-size or 100%. And 1:2 means one-half life size or 50% magnification. But that same person can't be sure if a 1:2 solution of A to water means a 50% solution or a 33% solution.

Wierd, how the Anguish Languish has great dynamic range, but poor resolution, and suffers from significant grammatic aberrations.

 

[Ian Grant]

Or a chemist.

If the two have indeed been used interchangeably by others in the past then such practice is nonsensical, UNLESS the "100" part in 1:1:100 is explicitly defined as "made up to 100 with water", " total parts of the mixture" or similar wording.

If the "100" part in this example is defined as pure water then no, the two conventions 1:1:100 and 1+1+98 are absolutely NOT the same.

Having worked as a photo-chemist and later running an analysis laboratory I find 1:1:100 completely meaningless, we used 1:10, 1:100, 1:1000 etc standard solutions with our equipment and these were ratios. You can't have a double ratio.

Ian

 

[GLS]

Having worked as a photo-chemist and later running an analysis laboratory I find 1:1:100 completely meaningless, we used 1:10, 1:100, 1:1000 etc standard solutions with our equipment and these were ratios. You can't have a double ratio.

It's simply a ratio of volumes of three separate ingredients; how is that meaningless?

Bringing dilution factors into the discussion (which I believe is what you are referring to) only adds another layer of potential (and needless) confusion.

I will illustrate the difference by giving you another typical real-world example, such as a working synthetic chemist uses every day. If a prep calls for the use of a 1:2 mixture of methanol:ethyl acetate, that ALWAYS refers to a ratio of the two different solvents, NOT a dilution factor of one into the other.

So, let's say for the sake of discussion we use 10 mL methanol and 20 mL ethyl acetate, making a mixture comprising 33% methanol by volume. If on the other hand we used 10 mL methanol and diluted it to 20 mL with ethyl acetate (i.e. adding 10 mL), we would have a mixture comprising 50% methanol by volume. These end results are totally different.

To reassure people that I'm not pulling this stuff out of thin air: I have two degrees in chemistry (including a PhD), and I work in the field of synthetic organic chemistry & medicinal chemistry for a living.

 

[Ian Grant]

It's simply a ratio of volumes of three separate ingredients; how is that meaningless?

Bringing dilution factors into the discussion (which I believe is what you are referring to) only adds another layer of potential (and needless) confusion.

I will illustrate the difference by giving you another typical real-world example, such as a working synthetic chemist uses every day. If a prep calls for the use of a 1:2 mixture of methanol:ethyl acetate, that ALWAYS refers to a ratio of the two different solvents, NOT a dilution factor of one into the other.

So, let's say for the sake of discussion we use 10 mL methanol and 20 mL ethyl acetate, making a mixture comprising 33% methanol by volume. If on the other hand we used 10 mL methanol and diluted it to 20 mL with ethyl acetate (i.e. adding 10 mL), we would have a mixture comprising 50% methanol by volume. These end results are totally different.

To reassure people that I'm not pulling this stuff out of thin air: I have two degrees in chemistry (including a PhD), and I work in the field of synthetic organic chemistry & medicinal chemistry for a living.

Keep it simple. In science we don't leave room for any ambiguity and you are arguing at cross purposes against yourself.

1 +1 made up to 100 is excavate the same as 1 +1 +98 however it's written and there's no ambiguity in that.

Ian

 

[GLS]

Keep it simple. In science we don't leave room for any ambiguity and you are arguing at cross purposes against yourself.

1 +1 made up to 100 is excavate the same as 1 +1 +98 however it's written and there's no ambiguity in that.

Ian

No, I'm really not. Everything I have written in this thread is correct and self consistent. We perhaps appear to be speaking at cross purposes with each other however; the bone of contention appears to be how you and I think a statement of X:Y should be interpreted by default. You seem determined on interpreting it only as a statement of dilution factors, whereas I (and every other synthetic chemist I have ever known) interpret it as a statement of ratio.

As to your second point, I have never claimed otherwise.

 

[Sirius Glass]

1:1:100 is exactly the same as 1 +1 +98 ie making up to 100 unless you're Kodak. Some companies used to put 1:10 (1+9) or 1:20 (1 +19) on their bottles for clarity. So you were agreeing with the poste before

Kodak use 1:3 to mean 1+3 = make up to 4 and is goes against the convention of the Dilution ratio that 1:3 means 1 part in a total of 3,

It's better to be clearer so I always say 1+1 to 100

As others stated you are wrong: 1:1:100 is exactly the same as 1 +1 +98 1:1:100 is NOT the same as 1 +1 +98. They are two different dilutions. Chemists, biochemists, chemical engineers, systems engineers, mathematicians, physicists, medical professionals, in fact much of the world would disagree with you.

 

[Patrick Robert James]

I'll sum up this thread-

Only on Photrio........

You guys are just blowing farts into the wind.

 

[Tony-S]

Kodak really caused problems with their notation. A 1:10 dilution is 1 part to 9 parts (i.e., 10^-1). Kodak doesn't use the colon for undiluted chemicals. When they say "D-76" in their data sheets they mean undiluted D-76 (i.e., 1:0). When they use "D-76 (1:1)" they mean 1 part D-76 to 1 part water (1+1). Ilford does it the right way.

 

[Vaughn]

I'll sum up this thread- Only on Photrio........You guys are just blowing farts into the wind.

And it is so much fun, we do it regularly!

I guess they taught us math wrong in school. We were always told that if there were two boys and four girls, the ratio between the number of boys and girls would be 2:4 (1:2), never 2:6 (1:3).

 

[jimgalli]

Dang it! A question even I could answer and when I find it, there's already 36 replies.

 

[MattKing]

These are always such entertaining discussions.
The problem, of course, is that different people, in different fields of operation and different geographical locations, using different languages, have different "shorthands" for an instruction like: "add one part A to one part B and then add water to bring the total volume to 100 (or 102) parts".
And if you try to use your shorthand version - i.e. the one that is viewed as "normal" in your group of acquaintances - then there is a good chance it will be understood as something else by others.
The "Kodak" shorthand is as good as any other approach - if one both understands the shorthand and is consistent in its use.

 

[Andrew O'Neill]

Dang it! A question even I could answer and when I find it, there's already 36 replies.

 

[Sirius Glass]

And it is so much fun, we do it regularly!

I guess they taught us math wrong in school. We were always told that if there were two boys and four girls, the ratio between the number of boys and girls would be 2:4 (1:2), never 2:6 (1:3).

We were taught correctly but some were not listening or smoking pot.

 

[foc]

It was mentioned already that Ilford give very simple and easy mixing instructions.

Ilfosol 3 developer 1+14, for example, means very simply, one unit of developer added to 14 units of water, no ambiguity there.
So if I want to mix developer for my tank that holds 300ml, I measure 20 ml of Ilfosol 3 and add it to 280ml of water. Can it get any simpler?

It reminds me of my mum's old cookbook from her schooldays, from which I learned how to make a basic white sauce.
The instructions were simple: 1 part flour + 1 part butter + 10 parts milk. I still use those instructions to this day (and I never get a lumpy sauce).

 

[Tom Kershaw]

For some reason I have tended to think of 1:9 as 1 part in 9. e.g. 100ml developer concentrate + 800ml water. Whereas 1+9 would be 100ml dev. concentrate + 900ml water. I'm probably wrong...

 

[MattKing]

For some reason I have tended to think of 1:9 as 1 part in 9. e.g. 100ml developer concentrate + 800ml water. Whereas 1+9 would be 100ml dev. concentrate + 900ml water. I'm probably wrong...

You aren't "wrong".
You are just using a different "shorthand" than was most likely being used by the developer's manufacturer, because Kodak (and some others) tend to use that to mean 100ml dev. concentrate + 900ml water.

 

[pentaxuser]

Given the differences we are arguing about it does tend to suggest that when we use the shorthand of 1:10 we need to expand this so there is no confusion as I think Ian Grant was suggesting. Presumably unless the ratios are small such as 1:3/4 or maybe 1:10 maximum then it may not really matter how we interpret it

pentaxuser ( when there is a party in swing as there often is on Photrio then a party pooper such as I is always a drag)

 

[Tony-S]

Given the differences we are arguing about it does tend to suggest that when we use the shorthand of 1:10 we need to expand this so there is no confusion as I think Ian Grant was suggesting. Presumably unless the ratios are small such as 1:3/4 or maybe 1:10 maximum then it may not really matter how we interpret it

The way I see it, ':' is ambiguous whereas '+' is not.

 

[Sirius Glass]

The way I see it, ':' is ambiguous whereas '+' is not.

One can have an option but the scientific and mathematical definition of the colon vis a vis ratios is clear to those who paid attention to there teachers, instructors and professors.

 

[RalphLambrecht]

I got a Pyrocat HD kit coming in for some sheet and roll film processing. I understand it calls for 1:1:100. So equal parts A & B to 100 parts water, ok. Wait. I don't get it.

Let's say I'm running 5 8x10 sheets in my Jobo Expert Drum. How many ML of A & B to how much water?

I prefer to call it 1+99.

 

[Tony-S]

One can have an option but the scientific and mathematical definition of the colon vis a vis ratios is clear to those who paid attention to there teachers, instructors and professors.

I am a professor. Virology and immunology of zoonotic diseases. My students and staff do this kind of math every day in my lab.