R9 bleach

[The_kodak_kid]

I’m using filmlabs r9 bleach recipe. I have all the necessary equipment and I already signed the safety precaution forms to buy the chemicals.

Only one question: the sulphuric acid I need to buy has to be 96%, but photographers formulary only sells 48%... does that mean that I double the amount of the 48% sulphuric acid??

Here’s the link to the recipe...
http://www.filmlabs.org/docs/toboldlygo.pdf

[nikonr10]

I’m using filmlabs r9 bleach recipe. I have all the necessary equipment and I already signed the safety precaution forms to buy the chemicals.

Only one question: the sulphuric acid I need to buy has to be 96%, but photographers formulary only sells 48%... does that mean that I double the amount of the 48% sulphuric acid??

Here’s the link to the recipe...
http://www.filmlabs.org/docs/toboldlygo.pdf

It's seem 's from all the posts ? ? you keep asking that you do not know what you are doing ?
Darkroom work is a skill / Art form which takes year's to learn .
Thing is other people read these's posts. I would not encourage anyone to start playing around with film Chemicals / reversal Bleach .
without kowing what there are doing or the skill's to handle in a safe place . yet alone sulphuric acid .

[Phil_F_NM]

I'm not even going to touch this other than generally discouraging it.
Just don't severely disable or kill yourself. Wear proper PPE which includes a respirator with the proper filtration.

Phil Forrest

[richard p. t.]

Yes indeed if its 48 or whatever percent just use twice as much. If it were 20% use 5 times as much. Battery acid is usually about this strength. You are quite correct.
Of course instead of sulphuric acid you can use 65 grams per ltre of sodium bisulphate. This is available from swimming pool soda as a ph buffer.

[nikonr10]

I'm not even going to touch this other than generally discouraging it.
Just don't severely disable or kill yourself. Wear proper PPE which includes a respirator with the proper filtration.

Phil Forrest

With no darkroom skill's ? / Phil is right Here , we should discouraging it .

[Phil_F_NM]

I don't want to discourage anyone's creativity but I DO want to stress safety. I have been in the position of being too eager before myself, years ago, and I learned from my mistakes. Cutting corners has led to a few completely botched jobs, minor property damage and me almost cutting my finger off. I was a kid, what can I say? I'm not encouraging the use of reactive, poisonous and cancer causing chemicals in a dark environment using open tanks, with likely dubious ventilation as well as PPE. A garage doesn't sound safe at all because of the things usually stored in the garage and the likelihood the space doesn't have proper positive ventilation. A garage with good light safe ventilation isn't a garage, it's a darkroom. 8 years in the Navy taught me this as well. I've used reversal chemistry but only in a hand operated sealed tank processor, after training, dry runs and supervision. The results still were marginal at best.
That is why I was encouraging the use of negative chemistry as it is merely 2 weak bases and a weak acid stop, if one choses to use a stop bath.
But in this case, the OP is going to do as they will and I can only stress they take the proper safety precautions with PPE and good ventilation though I'm doubtful this will be done.
I don't want to be a curmudgeon here as I'm new to the forum but burned lungs, blindness, poisoning from silver or otherwise are all easily preventable with training and proper equipment.
Phil Forrest

[nikonr10]

potassium dichromate is carcinogenic and should be handled with gloves and appropriate health and safety protection. The compound is also corrosive and exposure may produce severe eye damage or blindness.[13] Human exposure further encompasses impaired fertility, heritable genetic damage and harm to unborn children.
Then you want to play in the dark with buckets ? not forgeting the acid as well .

start by learning B/W film Chemisty the dos & dont's .

I don't want to discourage anyone's creativity but I DO want to stress safety.

There would have been something wrong had we not at least pointed out the risks / danger in this endeavour .

As many people come on to this forum to read posts or find info .

[The_kodak_kid]

Yes indeed if its 48 or whatever percent just use twice as much. If it were 20% use 5 times as much. Battery acid is usually about this strength. You are quite correct.
Of course instead of sulphuric acid you can use 65 grams per ltre of sodium bisulphate. This is available from swimming pool soda as a ph buffer.

Filmlabs instructions don’t mention anything about temperature. Do you know what the temperature of the bleach should be?