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Pyro - Obsidian Aqua

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UIMP

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Hi!
I've got Pyro obsidian aqua developer. I would like to ask you, how to develop Fomapan 400 film in this developer. I've got 2 bottles - part A and part B - what's the best proportions of this parts and water, the best time and agitation? Is 15 minutes a good time?
Regards
 

Rudeofus

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Following Hypercat's naming conventions (and Obsidian Aqua appears inspired by Hypercat), part A seems to be the stock concentrate containing the Catechol and the Metabisulfite, whereas part B would be the Carbonate solution that you dilute part A with.
 

rbultman

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There is a group on Flickr dedicated to pyro developers (Pyro Film Chemistry) that has a good thread on this developer. Jay DeFehr developed it. I have been following Regular Rod's development regimen to good effect. He develop's pretty much everything for 12 minutes with semi-stand agitation. Here is a link to a Google document that contains development times for many films:

https://docs.google.com/spreadsheet/ccc?key=0AgHnMiQ1qxIGdDUtTG1nZVBGUE00a1ZOMmRScTVGUGc#gid=0

There is a time there for Fomapan 400 of 15 minutes, but it is for 8x10. Are you using roll film or sheet film? What size, 35mm, 120, 4x5...? Are you developing using tanks? Assuming roll film and tanks, I would use a test roll and 12 minutes with semi-stand agitation, although I have not develop Fomapan 400 with OA.

As for dilutions, A is diluted 1:500, meaning 1ml of developer A concentrate in 500ml of water. The dilution of B depends on how you mixed the stock solution.

Let us know how your testing turns out!
 
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UIMP

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Thank you
I use 135 and 120 films and I develop my it in tank (Paterson Super System 4).
So, when I agitate like into the chart (0:10/3:00), how much part B i must use? Is 1A+1B+500ml of water good idea?
 

rbultman

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My only question is on how you mixed solution B. Can you send that information or a link to the recipe you used?

Sent from my Nexus 5 using Tapatalk
 
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OP

UIMP

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I got this developer from my friend. In his email he said that I must use 1ml of A + 5ml of B + 500 ml of water. In my previous post, there is a mistake.
What determines amount of part B?
In this dilution (1A+1B+500), what time i must develop Fomapan 400 in 20 Celcius degrees?
 

Regular Rod

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Hi!
I've got Pyro obsidian aqua developer. I would like to ask you, how to develop Fomapan 400 film in this developer. I've got 2 bottles - part A and part B - what's the best proportions of this parts and water, the best time and agitation? Is 15 minutes a good time?
Regards

31662981.c0dee546.2048.jpg


I use OBSIDAN AQUA all the time unless I'm using 510-PYRO

Here's how I make up my solution A and solution B. http://freepdfhosting.com/aa330a94ce.pdf

You need to know what formulation has been used for YOUR solution A and solution B.

I use an agitation regime that just about qualifies as semi-stand... The amazing thing about this developer is that you use the same time for all black and white, silver based, films of all speeds. I even develop 25 ISO films in the same tank with 400 ISO films. I have not used FOMAPAN 400 though but have used FOMAPAN 100 and 200 with satisfactory results. (My go-to 400 ISO film is ILFORD HP5 Plus.)

See page 2 here: http://freepdfhosting.com/3e906fe75d.pdf

RR
 

JLP

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Your friends suggestion to use 1 + 5 + 500 points to the Potassium Carbonate variant of OA. The Sodium variant would require 12.5ml of B since this is not as concentrated as the Potassium solution.
Try with 22 degree C.

I struggled with OA for a long time which Regular Rod can attest to. I am sure he pulled a few hair out trying to help. but, I have now found a couple of film that looks good in OA. Fuji Acros and Fomapan 200 both exposed at half box speed.
One important factor to consider is your enlarger type, If you are using a condenser enlarger I would cut a couple of minutes of the time Regular Rod suggest.
 

Regular Rod

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I got this developer from my friend. In his email he said that I must use 1ml of A + 5ml of B + 500 ml of water. In my previous post, there is a mistake.
What determines amount of part B?
In this dilution (1A+1B+500), what time i must develop Fomapan 400 in 20 Celcius degrees?

I'd say that was likely to be wrong. The right thing to do if the dilution is 1A + 5B: 500 is to take say 300ml of water, add 1 ml of A and then add 5ml of B then add water TO MAKE 500ml. You should have a total of 500ml NOT 500ml plus the quantity of A and the quantity of B...

Time for me would be 12 minutes at 20 Celsius BUT with constant, smooth, gentle agitation for first full minute then 10 seconds smooth, gentle agitation at 2 minute intervals until 1 minute to go and then pour out the developer at the full 12 minutes. IT IS BEST to pre-soak FOMAPAN for a full 5 minutes with smooth, gentle agitation every 30 seconds, I pour out and then rinse once more for a few seconds before pouring in the developer. NO STREAKS OR BUBBLES this way...

:smile:

RR
 
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UIMP

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Thank you, now I know, how it works, so, when I develop this film, I show you my results.
 

Monday317

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You folks all realize you've gotten the use of Jay DeFehr's Obsidian Aqua all mixed up? No wonder we're seeing bad/inconsistent results..! I am deliberately not calling the first OA (stock) solution "A" and the second solution "B" because it seems to be causing all the confusion. This ain't your father's ol' pyro, folks. The second solution is the diluent for the stock--you do not add water to make a working solution out of the first two mixtures! You just dilute the OA stock with the second solution; it needs the alkaline environment, but is extremely concentrated otherwise. To clarify:

1. Mix up the first OA (stock) solution as described, taking into account the info in the next step.
2. Mix up the second (diluent) solution; if you used sodium metabisulfite in the stock, you should use sodium carbonate in the second (diluent) solution; if potassium metabisulfite was used in the stock, potassium carbonate should be used in the diluent solution.
3. Take 1mL of the OA stock (the stuff with the catechol and metabisulfite) and add it to 500mL of the second solution, or diluent. That's it! You do NOT want to dilute further: this is not an ABC-type of sauce!

If I am reading some of the recent posts correctly, we have been looking at Obsidian Aqua as an A + B diluted with H2O to make a working solution kind of recipe, which is not the way this soup was designed. 250 grams of catechol in a liter of water is a very concentrated solution. The carbonate in the diluent provides the extra alkalinity to get the stuff to work--and work it will!

Google "Obsidian Aqua Film Developer" and read up on the stuff; it'll make sense to you I'm sure. Happy souping and have a terrific Memorial Day weekend wherever you live.
 
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pentaxuser

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I had thought that OA might be relatively simple in terms of mixing and use and it seemed that way reading RegularRod's link. Now we have a final post that seems to fly in the face of what RR suggests

To the best of my knowledge RR hasn't had any failures with his mixture or none he is admitting to so I wonder why he hasn't if what he is doing is wrong.

I said I'd stick with Xtol in an other thread and suddenly that looks like a good decision unless someone can clear up or reconcile what appears to be two diametrically opposed methods

pentaxuser
 

Regular Rod

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You folks all realize you've gotten the use of Jay DeFehr's Obsidian Aqua all mixed up? No wonder we're seeing bad/inconsistent results..! I am deliberately not calling the first OA (stock) solution "A" and the second solution "B" because it seems to be causing all the confusion. This ain't your father's ol' pyro, folks. The second solution is the diluent for the stock--you do not add water to make a working solution out of the first two mixtures! You just dilute the OA stock with the second solution; it needs the alkaline environment, but is extremely concentrated otherwise. To clarify:

1. Mix up the first OA (stock) solution as described, taking into account the info in the next step.
2. Mix up the second (diluent) solution; if you used sodium metabisulfite in the stock, you should use sodium carbonate in the second (diluent) solution; if potassium metabisulfite was used in the stock, potassium carbonate should be used in the diluent solution.
3. Take 1mL of the OA stock (the stuff with the catechol and metabisulfite) and add it to 500mL of the second solution, or diluent. That's it! You do NOT want to dilute further: this is not an ABC-type of sauce!

If I am reading some of the recent posts correctly, we have been looking at Obsidian Aqua as an A + B diluted with H2O to make a working solution kind of recipe, which is not the way this soup was designed. 250 grams of catechol in a liter of water is a very concentrated solution. The carbonate in the diluent provides the extra alkalinity to get the stuff to work--and work it will!

Google "Obsidian Aqua Film Developer" and read up on the stuff; it'll make sense to you I'm sure. Happy souping and have a terrific Memorial Day weekend wherever you live.

I had thought that OA might be relatively simple in terms of mixing and use and it seemed that way reading RegularRod's link. Now we have a final post that seems to fly in the face of what RR suggests

To the best of my knowledge RR hasn't had any failures with his mixture or none he is admitting to so I wonder why he hasn't if what he is doing is wrong.

I said I'd stick with Xtol in an other thread and suddenly that looks like a good decision unless someone can clear up or reconcile what appears to be two diametrically opposed methods

pentaxuser



"My" solution B is made up in a more concentrated form than the original recipe because it uses distilled water and is inconvenient to store such a large volume of sodium carbonate solution in the diluent strength. I took Jay's advice and made up the more concentrated solution of the sodium carbonate so that it was convenient to store and minimised the volume of distilled water needed to make up the solution. So... if anyone is using the recipe I use please DO continue to use it as solution A and B and add tap water to make up the working solution.

OBSIDIANAQUARecipe_zps0a3ab506.jpg


RR
 

Monday317

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I Stand Corrected

OIC, Rod. I agree, then and if it works, super! I'm a great admirer of your photography and must look into the whole Holganon business. I am working my own OA times using a nice old Zeiss Ercona, but your camera is giving me goosebumps! Since DI H2O isn't an issue, I'm using Jay's basic OA recipe.

Question: on my pretty good HP home monitor, I don't see much sky detail in your landscapes and some blown highlights. Is that from scanning, my monitor, or does OA prefer a little under-exposure? In any event your work is awesome, sir!

:D
 

Monday317

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I had thought that OA might be relatively simple in terms of mixing and use and it seemed that way reading RegularRod's link. Now we have a final post that seems to fly in the face of what RR suggests

To the best of my knowledge RR hasn't had any failures with his mixture or none he is admitting to so I wonder why he hasn't if what he is doing is wrong.

I said I'd stick with Xtol in an other thread and suddenly that looks like a good decision unless someone can clear up or reconcile what appears to be two diametrically opposed methods

pentaxuser
Not to worry: Rod's using a different road to get to the same destination by concentrating the B more as an activator, then diluting the two mixed, concentrated, solutions to working strength.

I misunderstood as I use Jay's original published recipe.:whistling:
 

Regular Rod

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OIC, Rod. I agree, then and if it works, super! I'm a great admirer of your photography and must look into the whole Holganon business. I am working my own OA times using a nice old Zeiss Ercona, but your camera is giving me goosebumps! Since DI H2O isn't an issue, I'm using Jay's basic OA recipe.

Question: on my pretty good HP home monitor, I don't see much sky detail in your landscapes and some blown highlights. Is that from scanning, my monitor, or does OA prefer a little under-exposure? In any event your work is awesome, sir!

:D

???

37037804.a629b399.1024.jpg


Time for you to get that Spyder on your monitor again... :wink:
:D
RR
 

pentaxuser

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Monday317, it looks like you have come to the same conclusion about your monitor as RR has but if it helps further to lead you to that conclusion I don't see any of the defects you mention on mine.

pentaxuser
 

Monday317

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???



Time for you to get that Spyder on your monitor again... :wink:
:D
RR
Well that one looks OK, but... :cool:

No doubt it's just the translation from neg to scanner to computer to net to blog to computer to monitor to my 60 year-old retinas to-- :crazy:
 

Monday317

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Monday317, it looks like you have come to the same conclusion about your monitor as RR has but if it helps further to lead you to that conclusion I don't see any of the defects you mention on mine.

pentaxuser
It doesn't--but I appreciate your suggestion all the same! :angel:
 

Regular Rod

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Well that one looks OK, but... :cool:

No doubt it's just the translation from neg to scanner to computer to net to blog to computer to monitor to my 60 year-old retinas to-- :crazy:

It could be my retinae. I'm a bit older...


:D
RR
 
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