help with low volume C41 processing

[LotusEsp]

I am a low volume 4x5 shooter; maybe 10 exposures a month, at the moment. But I expect that to increase in the new year.
I have a Jobo CPP2 with lift and expert drum - this works brilliantly for the the B&W stuff I've shot. but I really want to be processing my color film myself.

The only reliable source of chemicals I can find locally(ish) has the press type kits (unicolor etc) in 1 or 2 litre powder forms.

I have a couple of questions:

I am concerned about life of the mixed chemicals. Can they be reused? and for how long are they usable after mixing (and thus exposing to oxygen)?
If I am only using a small amount of the chemicals per batch (approx 50ml per sheet) would I be better trying to mix only portions of the chemicals before use or just mix the whole lot and store in containers with as little oxygen as possible?

thanks

[EdSawyer]

Check the sticky c41 thread here or at apug, I forget where it is.

[adelorenzo]

I use the Tetenal liquid kits which have an excellent shelf life. They also have a good capacity for re-use, they say 1 L does 16 rolls but as I'm only using max. 600 ml at any one time I normally run 20-24 rolls through a C-41 kit. You just follow the instructions to extend the developing and blix times as you process more rolls. You'd need to check the instructions for whatever kit you use obviously. I've used kits for up to 6 months without any issue.

When I had a large batch of important rolls to process from a trip I bought a 5 L kit—which is oddly only 50% more expensive than the 1 L kit—and did one shot development. Probably worked out to the same cost per roll.

[LotusEsp]

thanks

by shelf life, do you mean storing after you've mixed them?

Because of the difficulty in getting hold of the kits, I was tempted to buy up a few, and then mix 1/2 or a 1/3 of the powders at the time I need them (adjusting the water ingredient accordingly)
rather than doing the whole liter in one go, and only using 300ml of it at a time.

Would this be advisable or not?

[adelorenzo]

Yes I mean once I've mixed them. 10 sheets of 4x5 a month is 2.5 rolls/month. Personally I would have no concerns using a 1 L kit for 6 months/15+ rolls or more. Once again YMMV and you should check the instructions for whatever kit you buy. If you google it you'll see this is pretty typical for these kits.

With powdered chems I've always seen recommendations to mix them all at once. Otherwise you risk not getting things evenly distributed.

I use an acid stop bath before the blix stage, this was recommended by the esteemed Photo Engineer over on APUG.ORG. It helps keep your blix in good shape.

[rob4x5]

I use Kodak chemistry and mix it all at once. It lasts many, many months when I store it in glass bottles filled to the top and sealed tightly to prevent oxidation. I don't know how long your brand would last but in any case this would ensure maximum life.

[LotusEsp]

I use Kodak chemistry and mix it all at once. It lasts many, many months when I store it in glass bottles filled to the top and sealed tightly to prevent oxidation. I don't know how long your brand would last but in any case this would ensure maximum life.

Thanks
I am assuming you have separate bleech and fix then?

I cannot get hold of flexicolor in Toronto (without paying hundreds of dollars in shipping) so I am limited to the press kits with BLIX. As I understand it, it's the BLIX which doesnt keep for long after mixing, due to the two ingredients reacting to each other from the moment they are mixed.

[Wayne]

if the blix goes bad you can probably just reblix it with fresh chemicals.

[rob4x5]

LotusEsp, here is a link to a method of converting blix to separate bleach and fixer: http://www.apug.org/forum/index.php?...-and-fixer.74/

EDIT: Oops, after I posted, I realized you must become a member of the site to view it if you aren't already.

[LotusEsp]

LotusEsp, here is a link to a method of converting blix to separate bleach and fixer: http://www.apug.org/forum/index.php?...-and-fixer.74/

EDIT: Oops, after I posted, I realized you must become a member of the site to view it if you aren't already.

wow thanks Rob, thats a really cool link.

now I need to find out what Ammonium Bromide is, and if I can use:

HEXADECYLTRIMETHYL AMMONIUM BROMIDE
CETYLDIMETHYLETHYL AMMONIUM BROMIDE
TETRADECYLTRIMETHYL AMMONIUM BROMIDE



I may need to research this a bit more