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True speed for Acros...65, 100, 125 when developed in Pyrocat HD?

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Klainmeister

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Hi guys,

So I've been shooting Acros exclusively now (ya know, trying to be consistent for the first time ever) and have experimented shooting it at 64, 100, 125 with varying results. I develop in Pyrocat HD using the SBR list provided by Sandy, but am a bit confused. When I developed at ISO 64 in Pyrocat 1:1:100 with a(n) SBR 8 for 14 minutes I still ended up getting pretty harsh contrast. I adjusted to 100 and then 125 finding that these two are more desirable.

Just curious what others have found and recommend. I'm thinking 125 right now, but that was based on testing just a few rolls, so it's by no means extensive. I just want to get an ISO dialed so I can continue my path towards consistency. Any thoughts?

Thanks
 
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Klainmeister

Klainmeister

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No one out there? Sandy, maybe you can guide a young gun like me wee bit?

I'm heading to a ruin on the Colorado Plateau that I metered with an SBR of 9 last time I was there, so I wonder if I can actually pull detail out of the shadows and highlights this next trip soon, but I figure the proper ISO will greatly aid.
 

JLP

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I rate Acros at either 64 or 80 depending on the light.
Remember you don't adjust contrast by changing your Iso setting, you change contrast by changing developing time.
Try to reduce your dev time by 20% and still shoot it at 64 that is the speed i got back then when i used pyrocat.
 
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Klainmeister

Klainmeister

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Right, I was just curious as to which speed has the best response to the chart posted originally. I adjust time accordingly, but I just was curious if there's a 'sweet spot' so to say. Thanks
 

Vaughn

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How are you going to print these? For carbon printing, an SBR of 9 and either "normal" or a bit more development would be heaven! For silver gelatin printing, developing "normal" would be a disaster.
 

Andrew O'Neill

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How are you intending to print these negatives? On gel/silver papers? Alt process? A time of 14 minutes for that film in pyrocat-hd would be probably good for carbon printing but not on gel/silver, unless you are going for major N+ dev. If you are printing on gel/silver papers, what type of light head are you using?
Time to go back to the drawing board. Do test to determine an EI (probably 64 if you are printing on gel/silver and want nice shadows). Stick with a development time of about 8:30 at 21C. Once you have nailed down your EI, work out your N time. If 8:30 was good then you can work out N-, N+.
 
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Klainmeister

Klainmeister

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Thanks, that's the info I was hoping for. Right now silver printing seeing as though a 6x7 isn't much of a neg to make a contact print out of. I have a choice of using a Durst 1000 or a Omega Cold light. I haven't had much luck with the Omega, oddly. Too much contrast, hence my concerns over development time.

I guess I read the original posts regarding this combo in reference to alt printing. I'll do a test roll at 8:30 and see how that looks. The next coming weeks I have a set images already in my head that I know are going to be difficult to expose, so right now is the time to make mistakes and get it dialed.

ISO 64 @ 8:30 development. Sounds good. I'll hopefully posts some thoughts/results so that in the future anyone googling this info will have it more concisely represented.
 
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Klainmeister

Klainmeister

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BAD NEWS: I just shot and developed a roll, here's the stats. ISO 64, 1:1:00 @ 21c for 8:30 stand development.

My negatives are very thin. They are incredibly faint and I couldn't imagine pulling much off of them. When I did that same development for 15 minutes last week, the negatives were very dense...almost too dense.

Side question: I mixed a working solution last week (1 gallon) and used that same batch today. Does Pyro not sit well? When I used to use PMK I had the same issues. Sometimes everything looked beautiful and the next time I got super thin and faint negatives. I feel like I'm now having the same issue with Pyrocat as well...

Thanks guys, I know some of these are very newby-ish questions, but frustration is beginning to set in.
 

Barry S

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Pyro needs to be mixed fresh immediately before you use it. Yours oxidized before you used it.
 
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Klainmeister

Klainmeister

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That's the info I never had. Thank you. I have read so many people say "it's shelf life is great" but never quite knew if that meant working solution or the stock solutions on their own.
 

Allen in Montreal

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The pyro stock solution has a long shelf life, once you mix a working solution it becomes a one shot developer.
 

JLP

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In addition to the good suggestions already mentioned i don't believe you will get good results with just 8.30 minutes if you intend to use stand developement. Minimal agitation perhaps but no agitation will give you pretty flat negatives.
My time for 120 roll film is closer to 11 minutes with one minute initial agitation and then 10 seconds every minute. (Pyrocat MC 1+1+100 20C)
 
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Klainmeister

Klainmeister

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Interesting, so we're getting closer to the SBR list provided by Sandy many moons ago. My initial rolls were done in varying forms, ISO 64,100,and 125 and then between 10-17 minutes stand development. With everyone's thoughts and suggestions, I'm thinking the window for a base development time would be ISO 64 (or 80 even) and development around 11-14 minutes. Agitation is done for the first 45 seconds, then quarter, half, and three quarter breaks.

I never knew that "one shot developer" meant that once a working solution was mixed, it needed to be used at that moment. I assumed it just meant single use, throw away. Dope I am. That little piece of info could have probably saved me around...oh...10 rolls of good shots.

Thanks guys, as usual, very insightful.
 

JLP

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Many developers are meant to be used single shot, Rodinal is one, Xtol another but can be replenished but if used 1+1 or 1+3 it is single shot. The difference is that Pyro developers oxydize quikly when mixed whereas other developer doesn't and just need to be used within the hours. I don't know how long it actually keeps working strenght after mixed.
Pyro developers should be in contact with your film no more that a couple of minutes after mixing. Many mix while the prewash is taking place.
 
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Klainmeister

Klainmeister

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Noted, thank you. Not sure how I missed this key piece of information when I read Hutchings book about a year ago.
 
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