what was the last camera you used, last film and how was it developed

[abruzzi]

Thank's Abruzzi (your name recall's Italy),
I wonder why 1:2? Is it to restrain the rising contrast due to the pushing as Delta 3200 is actually a 1600ASA film?

And, I don't want to nit pick, but is it 1 / 2 or is it 1+2, as both characters ( : & / ) are a division character, I recall that AGFA was rather precisely about it...

I know this gets into the imponderables, but I've always taken 1:2 to mean 1 part xtol : 2 parts water. So 166ml xtol, and 333ml water.

I'll also add that I'm not a chemist, but a 20minutes and 75 degrees, the developer should have a lot of time and activity, so maybe the dilution is to pull back on the reins. Here is an example that was probably pretty close to 3200 (some of the shots were quite a bit darker) You can see it is somewhat high contrast (notice on the lower part of the status pedestal), but not horribly so:

 

[Andrew O'Neill]

Mamiya Six Folder. HP5. Xtol-R developed for box speed.

 

[Donald Qualls]

I'm glad I kept them during my digital adventures.

Good call there.

 

[murdockhendrix]

Kodak Brownie Hawkeye Flash model, Arista.EDU Ultra 200 (120), Photographers Formulary TD-16, dil 1:1, 9 mins, 20°C, developed @ home, inversion JOBO tank 1520.

 

[JerseyDoug]

Nikon F6, 24/85 zoom, Tri-X. Not developed yet. I'll probably use Ilfosol 1+9.

 

[FotoD]

I know this gets into the imponderables, but I've always taken 1:2 to mean 1 part xtol : 2 parts water

That's wrong. But most poeple write it the wrong way, so I guess that makes it right.

Writing it 1+2 makes it harder to misinterpret.

 

[Andrew O'Neill]

Canham 8x10 with 4x5 reducing back. CatLABS 80 II. Xtol 1+1, PC-512 Borax.

 

[GDI]

Chamonix 45N-2, Expired Tri-X, Rodinal 1+25, in a Jobo CPP2

 

[MattKing]

I know this gets into the imponderables, but I've always taken 1:2 to mean 1 part xtol : 2 parts water. So 166ml xtol, and 333ml water.

That's wrong. But most poeple write it the wrong way, so I guess that makes it right.

Writing it 1+2 makes it harder to misinterpret.

It isn't really wrong - it is just that writing it that way means one thing in one context and another thing in another context, so 1 + 2 is better.

 

[Sirius Glass]

It isn't really wrong - it is just that writing it that way means one thing in one context and another thing in another context, so 1 + 2 is better.

Not to someone who understood Algebra in middle school and chemistry in high school. Just ratio and proportions.

 

[GregY]

Perkeo ll,.....with the much maligned yellow filter..... Tri-X, Pyrocat HD. Print on Ilford Classic FB

 

[MattKing]

Not to someone who understood Algebra in middle school and chemistry in high school. Just ratio and proportions.

But where was your high school? It is a convention that varies in use depending where you are, and what your field of operation is. It happens to be the case that Eastman Kodak chose one variation - I wouldn't be surprised if Kodak Ltd. (UK) would have chosen another.

 

[abruzzi]

That's wrong. But most poeple write it the wrong way, so I guess that makes it right.

Writing it 1+2 makes it harder to misinterpret.

Ratio - Wikipedia

en.wikipedia.org

1:2 is standard notation for a ratio of one part of A to two parts of B

 

[FotoD]

1:2 is standard notation for a ratio of one part of A to two parts of B

Yes, if you are making a solution of substance A and substance B. If you are making a *dilution* (as with Xtol) 1:2 can read 1 part of substace A and solvent to make 2 parts in total.

But as Matt points out it depends on context. My comment was made in jest and you should keep doing what works for you. I find that writing it 1+2 removes some ambiguity.

 

[moggi1964]

Yahsica Minister 700; Ilford HP5+; lab developed as our house is a construction zone

 

[Donald Qualls]

writing it 1+2 removes some ambiguity.

Removing ambiguity is a worthy goal, IMO. With some developers, this matters less -- HC-110 Dilution B won't be a lot different if you use 31 parts water to one part concentreate; Rodinal 1:50 less so for 49 parts water vs. 50. But D-76 or Xtol (or Dektol, which is where I'm more likely to use low dilution since I run replenished stock for Xtol-alikes and D-23) confusing whether 1:2 means 1+1 or 1+2 can cause issues...

 

[TheFlyingCamera]

Century Master studio portrait camera, 8x10 Fomapan 200 (aka Arista.EDU Ultra 200). Film will be developed in Pyrocat HD 1:1:100 this weekend.

 

[Sirius Glass]

Ratio - Wikipedia

en.wikipedia.org

1:2 is standard notation for a ratio of one part of A to two parts of B

And that is the way it was meant to be read and understood. There is no ambiguity in the notation, only in the minds of those without the proper background education. Poor education leads to the misinterpretation that some push.

 

[MattKing]

And that is the way it was meant to be read and understood. There is no ambiguity in the notation, only in the minds of those without the proper background education. Poor education leads to the misinterpretation that some push.

And of course, if you are working with proportions, rather than ratios, than it is meant to be read and understood in a different way. And sadly, the "A:B" type of notation is used, in different fields, and different geographic locations in different ways - sometimes in references to ratios, and sometimes in reference to proportions.
It is like music, where the frequency standard for a particular note varies with geography - a piano tuned by a piano tuner trained in Vienna may be tuned differently than a piano tuned by a tuner trained halfway across the world.
On an international website, never assume that the "standards" you have been trained on are the "standards" that the well educated participants are using half way across the world.
Heck, don't make that assumption about standards that apply just up the coast in North America.

 

[fgorga]

Oh no... confusion over solutions and dilutions!!! Being a retired chemistry professor, I am quite familiar with this situation having taught beginning scientists for more than thirty years.

The bottom line is that there are no universal conventions with respect to notating dilutions. Different conventions are used in different fields. None are more or less "correct", but this does lead to confusion and ambiguity, as evidenced above.

Biologists generally write instructions for reducing the concentration of a stock solution as "1:9", for example. Meaning that one takes 1 part of stock and adds nine parts of solvent. The notation that some photographers use (e.g. "1+9" following the above example) is really just a variation of this convention. It may be a bit less ambiguous that writing the ratio, but one still needs to understand the convention.

Chemists generally write the same instructions as "1:10". Meaning that the final solution contains 1 part of stock in a final volume of 10 parts.

Both conventions yield the same final solution (at least for dilute solutions; for very concentrated solutions the chemist's convention is better if one cares about the precise concentration).

Chemists argue that their convention is 'better' because the final concentration is clearly indicated... i.e. in the above example the concentration of the final solution is 1/10 (one tenth) the concentration of the stock solution.

Biologists argue that their convention is 'better' because the 'recipe' is clearly indicated... i.e. one would take 1 volume of stock and add 9 times that volume of solvent.

Bottom line: Take your pick of either convention, stick with it and make it clear which one you use when communicating with others.

 

[Donald Qualls]

make it clear which one you use when communicating with others.

This is key.

"One part stock solution to one part water, develop prints two minutes consistently" for Dektol is a lot clearer (especially for those without either chemistry or biology background) than "Develop one minute for each dilution step" which I've seen seriously suggested in that form.

 

[murdockhendrix]

Bronica EC-TL, Ilford XP2 Super
Agfa Clack, Kodak Gold 200
Developed @ home, JOBO CPE+, Cinestill CS-41, 3:43 mins, 39°C, JOBO tank combo (1510 + 1530, 470ml)

 

[Helios 1984]

I found a 20+ years old of spent roll of Seattle Filmworks ECN-2 motion picture film at a thrifstore and developed it by curiosity.

- 3 minutes wash in baking soda solution to remove the remjet (most of it anyway)
- 3:30 minutes in my 41 months old batch of Unicolor C-41
- 10 minutes in Blix
- The mandatory wash
- Removal of the remaining remjet
- 2 minutes in Kodak Final Rinse

Success

 

[Sirius Glass]

Accidentally a roll of Tri-X got into a UltraColor box and a roll of film shot in Kauai turned out to be black & white.

 

[Mr Flibble]

Roll of Ilford HP5+, shot with a 1938 Balda Super Pontura, exposed as 400ASA

Developed in Kodak HC-110, dilution E for 7:30min at 20C
30 seconds initial agitation followed by 1 inversion every 30 seconds.