Editing Darkroom/C-41RA Film Development

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C-41RA is a rapid, three-bath process for developing ordinary C-41 colour negative film.  It comes as a kit;  popular brands are Tetenal and Arista, and they're often called press kits because newspaper photographers used to use them.  C-41RA chemistry is a lot like B&W in use, except that it doesn't last as long, hates oxygen, and needs accurate temperature control to work well.  The chemistry only lasts about three weeks once mixed, and I get about forty 135-36 filmsworth out of a one litre Tetenal press kit, as long as I *religiously* purge the bottles with Dust-Off after I use the chemistry.
C-41RA is a rapid, three-bath process for developing ordinary C-41 colour negative film.  It comes as a kit;  popular brands are Tetenal and Arista, and they're often called press kits because newspaper photographers used to use them.  C-41RA chemistry is a lot like B&W in use, except that it doesn't last as long, hates oxygen, and needs accurate temperature control to work well.  The chemistry only lasts about three weeks once mixed, and I get about twenty 135-36 filmsworth out of a one litre Tetenal press kit.
 
All C-41 film needs the same development, so there's no complicated film-specific developer time matrix of doom.
 
==Important Safety Tips==


C-41RA blix is toxic and nasty;  don't get it on your hands, clothes, or in your eyes or mouth.  The developer's pretty unpleasant too, but the blix is a special kind of assholish chemical.  All three of the major components are probably carcinogenic, so yeah, you might want to wear gloves when handling them.  You'd be a special kind of jerk to leave it, or things that have touched it, where people might be handling food.  Keep chemistry away from food, animals and children.
C-41RA blix is toxic and nasty;  don't get it on your hands, clothes, or in your eyes or mouth.  The developer's pretty unpleasant too, but the blix is a special kind of assholish chemical.  All three of the major components are probably carcinogenic, so yeah, you might want to wear gloves when handling them.  You'd be a special kind of jerk to leave it, or things that have touched it, where people might be handling food.  Keep chemistry away from food, animals and children.


When your chemistry's spent, dispose of it carefully;  the developer is okay to pour down the drain with plenty of water, but the blix has silver compounds in it so needs to be de-silvered before disposal.  The stabilizer has hydrazine and (when used) formaldehyde in it.  Dispose carefully.  Both the blix and the stabilizer will gradually off-gas in the bottle, so don't leave them on the shelf too long unless you want to see the bottle blow its top.
All C-41 film needs the same development, so there's no complicated film-specific developer time matrix of doom.   
 
If you get any of these chemicals in your eyes, get someone to force your eye open and flush under running water for several minutes, and then get them to take you directly to the eye hospital.  I am not even kidding.
 
Everything you use in this process needs to be totally free of grease, soap, and other impuritiesColour film is a complicated chemical system that revolves around selectively monkeying with dye molecules, and a couple dabs of soap on your processing drum will totally ruin the developer.


==Before You Start==
==Before You Start==
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# Make up your chemistry according to the instructions.  You'll need three bottles to put it in.
# Make up your chemistry according to the instructions.  You'll need three bottles to put it in.
# Mark your bottles:  Developer, Blix and Stabilizer.  Don't mix them up.
# Mark your bottles:  Developer, Blix and Stabilizer.  Don't mix them up.
# Make up a tempering bath and heat it to 100.3 degrees Fahrenheit.  Or 38 degrees Celsius.  It doesn't have to be closer than half a degree or so.
# Make up a tempering bath and heat it to 100.3 degrees Fahrenheit.
# Put your chemistry bottles in the tempering bath and wait for them to get to temperature.
# Put your chemistry bottles in the tempering bath and wait for them to get to temperature.
# Make sure your tank, spiral, and bottles are compatible with colour chemistry, because some plastics aren't.  The Paterson tanks are.  Glass bottles aren't.  No, really.
# Make sure your tank, spiral, and bottles are compatible with colour chemistry, because some plastics aren't.  The Paterson tanks are.  Glass bottles aren't.  No, really.
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