C-41 Times, doh!

[markbarendt]

I've been using Trebla's chemicals for my C-41 film for maybe 9 months +/- and getting good results.

Well it's near time for me to restock and since I now actually have a a bit of experience with C-41 I figured doing some research before I bought more would be productive, I was right.

Well what I learned is that I've been wasting a bunch of time.

I just (and this is my "doh!") "assumed" the standard Kodak times Dev 3'15", Bleach 6'30", Wash 3'15", Fix 6'30", Wash 3'15", Stabilize 1'30" were standard for the industry across all the chemicals.

Doh, doh, doh!

The PDF's I needed to understand this were a bit tricky to find, which is one of the reasons I missed this in the first place but I learned that times are not standard.

So here is my new regime inserting Trebla's times for the chemicals I actually have. I linked the PDF's here to make life easy for others.
_________________________________

TL-50 Developer @ 100f - 3’15” at least this remains the same

C-41RA Bleach @ 95f - 0’45” Minimum, extra time is allowable

Wash - 5x fill, agitate 0"30", and dump - ~ 3'00"

C-41RA Fix @ 95f - 1’30” Minimum, extra time is allowable

Wash - 5x fill, agitate0"30", and dump - ~3'00"

ELF Stabilizer @ 95f - 1’00” Minimum

Dry
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Cuts my total time roughly in half.

Hope this helps others avoid my mistakes!

Doh!

 

[kauffman v36]

i have a question, i am going to attempt dev. technical pan in c41 dev as some have done but i need JUST the developer, can you point me in the right direction to just a developer, small quantity preferred. and instructions if you can, i am totally lost when it comes to c41

 

[Photo Engineer]

Mark;

The bleach and fix times are much too short IMHO. No EDTA or NTA based bleach will work in that time, nor will any ammonium based fix work on those thick color films. The wash times are sort of skimpy too!

This might be for C41-RA chemistry, but even so, the wash is short. In those cases, a special stabilizer is used to allow for the short wash.

PE

 

[nickandre]

i have a question, i am going to attempt dev. technical pan in c41 dev as some have done but i need JUST the developer, can you point me in the right direction to just a developer, small quantity preferred. and instructions if you can, i am totally lost when it comes to c41

Buy the one gallon developer from Adorama. It mixes ABC as written on the box.

Mark,

The C41 RA chemistry is usually only supplied in Minilab cartridges. Kodak does sell the SM bleach alone which works in a minute as well. I had doubts so I used more like 2.5 minutes but as far as I can tell it's bleached after 1 minute.

I've also noticed that the regular C41 fix clears the film in ~30 seconds but we're supposed to wait 6.5 minutes. Do I know why? No. But it's just as easy for me to walk away for 6 minutes than it is for me to stand there for one so I give it the full time.

 

[markbarendt]

Mark;

The bleach and fix times are much too short IMHO. No EDTA or NTA based bleach will work in that time, nor will any ammonium based fix work on those thick color films. The wash times are sort of skimpy too!

This might be for C41-RA chemistry, but even so, the wash is short. In those cases, a special stabilizer is used to allow for the short wash.

PE

I'm confused now because I also looked at Kodak's SM chems and they show very fast times too.

Given your thoughts here and Trebla's instruction that the times listed are: the minimums, and that they should not include pour and dump, and that longer times are okay. I can see where extending the bleach and fix times some could be prudent.

 

[markbarendt]

The C41 RA chemistry is usually only supplied in Minilab cartridges.

I agree that sourcing is "interesting" and sizes are larger but bottles are available from the minilab supply shops.

That's part of what got me into my doh. I bought a Trebla kit but there were no instructions, other than how to mix up a big batch; minilab supply houses expect their clients to know how they work.

I had to figure out all the ratios to be able to mix up enough for smaller batches and didn't find the Trebla PDF's until yesterday.

I've also noticed that the regular C41 fix clears the film in ~30 seconds but we're supposed to wait 6.5 minutes. Do I know why? No. But it's just as easy for me to walk away for 6 minutes than it is for me to stand there for one so I give it the full time.

Glad you posted this, I want to get past the myths, superstitions, and hedges in my process.

I'd rather agitate for the full recommended time, if that's all it really takes.

I don't really multitask well, when I walk away I tend to get distracted and come back late.

 

[Photo Engineer]

Use the time/temp guidelines I posted in the other C-41 thread.

PE

 

[Photo Engineer]

Here is why C41 bleaches and fixes are so slow.

C41 color films contain DIR couplers and high iodide emulsions. These materials adsorb to the surface of silver metal and silver halide, and prevent complete fixation and bleaching. It requires either a long time or special ingredients to achieve the proper fixation and bleaching. I was part of this investigation team. I know that the RA fix is designed to allow rapid removal of silver halide in the presence of DIR fragments and Iodide. I have not studied the RA bleach, but there are special chemicals in the RA fix. This also allows more rapid washing.

PE

 

[Athiril]

i have a question, i am going to attempt dev. technical pan in c41 dev as some have done but i need JUST the developer, can you point me in the right direction to just a developer, small quantity preferred. and instructions if you can, i am totally lost when it comes to c41

Easy, you're in the U.S. get it from Adorama or B&H or any of the other numerous online shops you guys got.

You can get just developer in Kodak and Fuji chemicals.

 

[mts]

Except for the developer the C-41 process solutions go to completion. Bleach, fix, wash, and stabilizer are not time critical providing that sufficient time is allowed and the solutions are not exhausted. Follow PE's times. Don't try to cut times to a minimum because you run the risk of having incomplete bleach or fix, poorly washed or unstabilized film.

 

[markbarendt]

Except for the developer the C-41 process solutions go to completion. Bleach, fix, wash, and stabilizer are not time critical providing that sufficient time is allowed and the solutions are not exhausted. Follow PE's times. Don't try to cut times to a minimum because you run the risk of having incomplete bleach or fix, poorly washed or unstabilized film.

mts

I agree that we shouldn't short change the times. But... what I'm saying, and PE has actually alluded to (even while suggesting longer times), is that it takes "different" chemicals to shorten the cycle.

I want to be clear here, I'm not suggesting non-standard times, I'm suggesting that the manufacture knows what their chemicals will do. All I did (finally) was read the directions for the stuff I was using.

The chemicals listed in this post are not the "generic" Bleach III and flexicolor fixer where the manufacturer's time is specified at 6'30".

The manufacturer's time specs for Kodak's SM chemicals are 1 minute bleach and 2 minute fix. For Trebla's chemicals it's 45 seconds bleach and 1'30" for fix.

It would seem these chemicals were designed to be faster than the "generic" stuff.

Adding some extra time won't hurt but even doubling the manufacturer's specs for the Trebla chems only gets us to 1'30" for bleach and 3' for fix.