weigh the volumes

[schyter]

Good morning everyone, (sorry for my english...)

in an Italian forum I have been ridiculed by many users, because I proposed to a guy who was starting for the first time to develop black and white, not to buy jugs, syringes and graduated cylinders.
Could replace this with a simple precision balance (0,1gr ebay 10$); the advantage of this solution, are in my opinion, in order of importance :

>> economic savings >> no annoying washing, with the risk of breakage >> repeatability accuracy and higher precision.

The important thing is to know the specific gravity of the chemical, but practically all the manufacturers on the report in datasheets or MSD.

Here's an example .

APH09 Adox (Rodinal) 1 +50 (specific gravity 1.36 )
Tank AP 590ml necessary for one 120 roll

590ml / 1 +50 = 11.57 ml X 1.36 (SG) = 15.7grams APH09
11.57ml X 50 = 578,5ml === 578.5grams of distilled water

15.7gr APH09 + 578.5gr of distilled water = 594.2grams of developer!

How to >> put an empty bottle on the balance and tare to zero.
Put 15.7 grams of APH09 and tare to zero.
Put 578.5 grams of distilled water

Things become even more important when you are using multiple solutions (A+B+C)... How many cylinders, jugs, and syringes avoid washing?

1> I think I have a good precision .
2> I think I have a good repeatability.
3> I do not have to wash superfluous.
4> I saved money without compromising accuracy.

because this system has created a cruel irony and derision ???
I've made mistakes ???

Many thanks at all !! Luigi ;/)

 

[pdeeh]

it seems pointlessly complicated

 

[darkosaric]

Welcome to APUG Luigi .

I would say keep it simple, this what you are suggesting is too complicated.
I use APH09 in very simple way: 7ml of APH09 in 7dcl of water - this makes 1+100 dilution. A that's it. Cheap, repeatable, precise, accurate.

 

[schyter]

many thanks...
is really quite simple, just write on the bottles of the developers, the specific gravity once. I use this method for several years at a profit.
I just wanted to understand if I'm committing a serious mistake that it can not be
recommended for those who must buy for the first time the material for the first development.

 

[paul_c5x4]

The cost of a couple of graduated cylinders, especially if you are buying off ebay, is minimal. Syringes can be had for free (local chemist supplies free packs for drug addicts) - Washing is simply "rinse a few times and leave to drain". Even if you are using scales, you would still have containers to wash afterwards.

Not to ridicule, but your method is overly complicated and prone to error - What happens if you don't have the S.G. listed for that one important chemical ?

 

[TheToadMen]

Hello Luigi,
I can't help you with this topic, but just wanted to welcome you to APUG.
Another pinhole shooter in Europe, like me

Bert from Holland
http://thetoadmen.blogspot.nl

 

[schyter]

many thanks to all ! ;/)

Paul > if you use a plastic bottle for water, you can just throw it in the waste basket. I want to clarify that it is a proposed method to a guy who develops the first time, with a few budget.
I do not want to expose myself stubbornly, but I do not understand why it is prone to errors.
I believe the opposite. ;/)

 

[Rick A]

Every method is prone to error, the more complicated the method, the more likely for error. There is an old saying, keep it simple. The mixing ratios are usually listed on the containers we buy, following the instructions and ratios is simple, and should help avoid mistakes.

 

[TheToadMen]

I know of an international project that was calculated, measured, methodist, audited, double checked, logged, etc. But when it was finally tested in real life, it didn't work as expected.
Someone forgot to mention that one side of the ocean inches were used for measurements, and centimeters on the other side.

It's al in the details .... :munch:

 

[schyter]

Hi guis,

maybe my approach to printing with ancient techniques (cyano, vdb, kallitypes etc etc)
made me confident with the method of weighing. In reality, I also had objective evidence to my methodology >

http://www.chimicare.org/blog/filos...a-volumetria-ragionamenti-e-consigli-pratici/

so I thought... the classic method has same remained for so long time, because the only tool that was not available to amateur photographers for few dollars, was a precision balance! ;/)

 

[Rick A]

Here's my take on weighing anything. Weight varies by location, and moisture absorption. Water can have different weight due to location , and dissolved mineral content (even distilled water can vary). Photography is a process(or series of )that we strive for consistency, not total accuracy(there are far too many variables for that). I weigh dry chems to make up some of my developer formulae, but once mixed, volume takes over. I, and nearly all here, strive to be as perfect as the process will allow, but in the end, we all have our own methodology that gets us to the desired result. I, like so many others, seek convenience of the easiest and most repeatable steps to finished product. We are not machines, and are prone to mistakes, simplification reduces the chances for error.
I am impressed that you have taken much pride in your method, and seek perfection in such (as I see it) a tedious procedure.
BTW, welcome to Apug, we have much to learn, from each other.

 

[ic-racer]

You have to put the liquid into something when you put it on the scale. Why not put the liquid in a graduate cylinder and then you don't need the scale. But then you need to find what works best for you.

 

[schyter]

You have to put the liquid into something when you put it on the scale. Why not put the liquid in a graduate cylinder and then you don't need the scale. But then you need to find what works best for you.

why not buy it and do not wash. Use a plastic bottle of water to which I cut the neck.

 

[giannisg2004]

Good morning everyone, (sorry for my english...)

in an Italian forum I have been ridiculed by many users, because I proposed to a guy who was starting for the first time to develop black and white, not to buy jugs, syringes and graduated cylinders.
Could replace this with a simple precision balance (0,1gr ebay 10$); the advantage of this solution, are in my opinion, in order of importance :

>> economic savings >> no annoying washing, with the risk of breakage >> repeatability accuracy and higher precision.

The important thing is to know the specific gravity of the chemical, but practically all the manufacturers on the report in datasheets or MSD.

Here's an example .

APH09 Adox (Rodinal) 1 +50 (specific gravity 1.36 )
Tank AP 590ml necessary for one 120 roll

590ml / 1 +50 = 11.57 ml X 1.36 (SG) = 15.7grams APH09
11.57ml X 50 = 578,5ml === 578.5grams of distilled water

15.7gr APH09 + 578.5gr of distilled water = 594.2grams of developer!

How to >> put an empty bottle on the balance and tare to zero.
Put 15.7 grams of APH09 and tare to zero.
Put 578.5 grams of distilled water

Things become even more important when you are using multiple solutions (A+B+C)... How many cylinders, jugs, and syringes avoid washing?

1> I think I have a good precision .
2> I think I have a good repeatability.
3> I do not have to wash superfluous.
4> I saved money without compromising accuracy.

because this system has created a cruel irony and derision ???
I've made mistakes ???

Many thanks at all !! Luigi ;/)

Your method is scientifically correct.
But it's too complicated or a beginner.

And in the end, I don't think you save any money or effort.
A precision scale costs more than a couple plastic cylinders/beaks.
And when measuring the chemicals, you still need a container to put them in when weighting them.

Say for instance I'm developing in Perceptol 1+3 at a 400ml tank.

- With the usual method, you get a cylinder and start pouring developer until you hit the 100ml mark.
You add water until you hit the 400ml mark and that's it.

- With your method, you need to calculate the required weight of Perceptol (supposing you have its sp. gravity).
Then the same for water.
And then still use a container where your pour the chemicals to weight them to the required amount.

I don't see how it's cheaper or simpler, especially for a beginner.

 

[schyter]

thanks Gianni,

<< And then still use a container where your pour the chemicals to weight them to the required amount. >>

is not correct... I only use a bottle on the scale !! I put the required grams of developer and water.

Perceptol 1+3 (stock 1.110 SG >> http://www.ilfordphoto.com/Webfiles/2011427133131459.pdf pg.2)

100ml X 1.11 SG == 111gr + 300gr distilled water OR 111gr Perceptol (stock) and distilled water until reaching 411gr on the scale !

no jug, no cylinder, no washing and no purchase. Excellent repeatability. Obviously do not want to convince anyone... ;/)

 

[darkosaric]

I guess this is your favorite story (no hard feelings):

http://www.goodreads.com/quotes/167442-once-upon-a-time-powerful-wizard-who-wanted-to-destroy

 

[BrianShaw]

Some bakers will develop/adapt their bread recipes to weigh liquids rather than using fluid measures. They are always in the minority... and they are often ridiculed.

 

[schyter]

I guess this is your favorite story (no hard feelings):

http://www.goodreads.com/quotes/167442-once-upon-a-time-powerful-wizard-who-wanted-to-destroy

( no hard feelings ) I knew, but I had not thought of that.!!! ;/) ;/) many thanks...!

http://www.chimicare.org/blog/filos...a-volumetria-ragionamenti-e-consigli-pratici/

and for bakers... >>

(cit.)In my personal experience I have had the opportunity to accumulate a whole series of arguments between their very different, however, almost unanimously agree that enhance the choice of gravimetry (noble name to indicate the weight measurement, using scales), at the expense of the volume for both the measurement for the determination of substances, both liquid and solid, not only in the reality of chemical laboratories, but wherever there is the need to measure the amount of a given material in bulk, so even in the kitchen and in workshops. (no hard feelings)

greetings from italy! Luigi ;/)

 

[giannisg2004]

thanks Gianni,

<< And then still use a container where your pour the chemicals to weight them to the required amount. >>

is not correct... I only use a bottle on the scale !! I put the required grams of developer and water.

Perceptol 1+3 (stock 1.110 SG >> http://www.ilfordphoto.com/Webfiles/2011427133131459.pdf pg.2)

100ml X 1.11 SG == 111gr + 300gr distilled water OR 111gr Perceptol (stock) and distilled water until reaching 411gr on the scale !

no jug, no cylinder, no washing and no purchase. Excellent repeatability. Obviously do not want to convince anyone... ;/)

There's nothing wrong with your method.
And it's actually the only way to do it when your mixing your own developers from raw chemicals.

I just think the volume method is easier.

For instance you said you use a bottle to weigh the chemicals.
I use a beaker instead of the bottle.
You use the weight on the scale, I use the markings on the beaker.
It's almost the same thing.

 

[RalphLambrecht]

many thanks...
is really quite simple, just write on the bottles of the developers, the specific gravity once. I use this method for several years at a profit.
I just wanted to understand if I'm committing a serious mistake that it can not be
recommended for those who must buy for the first time the material for the first development.

works for mebut maybe not for everyone;who cares as long as it works for you?There is more than one right way!

 

[Truzi]

It is an interesting idea, but I do not think it is good for a beginner who does not have appropriate knowledge of such things. There is nothing wrong with the idea, but it seems more "advanced" to me. Most people do not even understand the concept of specific gravity, despite it being covered in most high school science classes (if not earlier).

I think a beginner would have an easier time doing what they are more familiar with in every-day life, which would probably be measuring fluids by volume.

 

[schyter]

There's nothing wrong with your method.
And it's actually the only way to do it when your mixing your own developers from raw chemicals.

I just think the volume method is easier.

For instance you said you use a bottle to weigh the chemicals.
I use a beaker instead of the bottle.
You use the weight on the scale, I use the markings on the beaker.
It's almost the same thing.

However the glasses, carafes and syringes, need to buy and wash... my plastic bottle commonly used (PET) I can delete it in the garbage can.

 

[gone]

Please see the thread on the forum here, below, on a lower level than this, as a specific idea on the probable complications of simplicity, with some concrete and suggested alternative correlations, yet seen as a priori (or posteriori) cognitive approach to confined thinking through multiple layers of visual development, vis a vis a presentation using contemporary video/verbal/audio signage.

Or, buy a syringe from the drug store, a measuring cup from the thrift store, and follow the directions on the packages.

(there was a url link here which no longer exists)

 

[AgX]

However the glasses, carafes and syringes, need to buy and wash... my plastic bottle commonly used (PET) I can delete it in the garbage can.

For b&w one can cope with 1 graduated beaker (as available in a kitchenware shop/department) and 1 small volume graduate (alternatively 1 plastic syringe + wide gauge needle)

The needle should be grounded flat and the graduate may be not that easy to come by locally. But still these 2 prerequisites should not form an issue. At least not compared to that balance.

I do not understand the problem of washing (rather rinsing). I guess one washes a multiple of glasses, plates and forks daily than those two items. Furthermore the tank and reel must be rinsed anyway.

 

[NedL]

Greetings Luigi,

Very happy to see you here and welcome to APUG!

I think there is nothing wrong with your approach. It has the benefits you describe, and there is nothing wrong with it for you. You already have a lot of experience.

I think it is not the simplest approach for a beginner.

Ned