Help learning C-41 processing

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totowroe

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I have never developed anything beyond black and white film. A close friend recently gave me a box of Superia 400 and a few rolls of Ektar. After shooting them, I called up the local labs to see how much it would cost to have them processed--$7.00 US.

I figured since I've developed B&W that color wouldn't be an issue, but GOOD LORD. 100 degree water and all those chemicals!?

Two questions I hope you will answer~

1. Is it practical to do my own C-41 processing instead of taking film to the lab? I currently shoot 1-4 rolls every two weeks in B&W and process them on my own (which I enjoy), but would MUCH rather shoot in color because color is nice.

2. Could you link me to a page/thread with easy to understand steps of how to process C-41 film? I don't do well with long/convoluted write-ups since I'm pretty dumb, so a series of steps or an outline is best. (I've already bookmarked a few like this, but I bet you know of some better ones).

Thank you for reading. Questions along these lines have probably been asked a million times one way or another, so I appreciate your understanding.

Bonus question: How do you keep your water at 100 degrees? Do you use an aquarium heater?
 

Mike Wilde

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The processing does require good temperature control, and consitent agitation for repeatable results.

Yes, I temper my chemistry in a 14L cooler fitted with a 300W aquarium heater with a mechanical bi-metalic lead screw controlled dial mechanism modified to heat to 100F. I added an aqaurium circulation pump whan I wanted the cold chemicals to come to temperature faster.

There are differnt processes; here is the one I use, which is somewhat modified to cut carry over when using a small tank:

3:15 developer, agitate 2 seconds per 30 seconds.

45: stop bath. Agitate gently continuously.

1:00 water wash

6:00 bleach

2x1:00 water rinse

4:00 fix.

4:00 wash

1:00 final rinse, not on the spool.

Hang to dry in a dust free place.

All solutions other than developer very near 100F.

The world wont end if you flx is down to 92F because you unplugged the heater because you were laldling rinse water from the water bath.

I am not main stream; I mix my c-41 from raw ingredients.
There are commercially available kits, that work quite well, and can process on the order of 8 rolls in 1 L of solution.

I beleive the kits work best if they are used moderately soon after the first use before running the second.etc. tanks, so you may need to save up some films, and process a month worth of shooting in a few nights.

Good luck.
 

Chris Douglas

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Toto,

C-41 is easy if you can get constant temperatures. I use a plastic dishpan with an old waterbed thermostat (yes I had one...what were we thinking?), a cooler pump to circulate the water, and a hot water tank heater element. A 1500 watt 220 volt element gives about 300 watts on 110 volts which is just perfect, and costs under 10 bucks. Have fun.

Best regards,
Chris
 

mts

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Or just fill the dishpan with hot water ~130F, wait until temperature drops to about 105F, then add hot water to bring temperature up to ~120F. When the temperature drops to 101-102 as measured by a color thermometer in the developer bottle, start processing. The tempering procedure takes about 20 minutes in my darkroom sink. You process C-41 for less than four minutes. In between agitations I simply hold the SS tank in the water bath.

Follow developer with stop, then a brief wash. Everything else works to completion so temperature is not critical, but keep things between 90-100F to avoid thermal shock that could possibly cause reticulation. You don't need any electrical connections to your water bath and in my opinion it is a very good idea not to have them there. If you are going to process more than one tank's worth of film, then simply add more hot water from the tap and repeat the procedure.

It is important to put a wash/rinse following the stop and the bleach, and of course a final wash following the fixer. I do this using water from the tap hose by adjusting the temperature to about 95-100F, and find it is easy to do. When I am processing C-41 or E-6 I store the solution bottles in the washpan in the sink. They get a little scummy looking on the outside but that does not affect the content. Glass bottles are preferred of course especially for the developer, but nalgene works well too.
You just need to understand that temperature must be accurate for only the developer (C-41) and for the first and second developers in E-6. Once you develop a work flow procedure it's not at all difficult to be consistent in your processing.
 
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totowroe

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Thanks for the quick, EXTREMELY HELPFUL replies. The Youtube video was awesome, although the host was pretty silly. Another question~

1. Does ISO speed affect developing times? Can I develop two films with different ISO speeds together? What if I want to push process?
 
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markbarendt

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Thanks for the quick, EXTREMELY HELPFUL replies. The Youtube video was awesome, although the host was pretty silly. Another question~

1. Does ISO speed affect developing times? Can I develop two films with different ISO speeds together? What if I want to push process?

The normal C-41 process is always the same 3:15 developing times. You can mix and match any ISO and any brand in the tank.

You can push too by adding development time. See Kodak's tech pub for more info. Again all ISOs, all brands, same times.
 

mr rusty

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Just building my very first darkroom. Only intend to do B&W at first, but it struck me that one of these could be very useful http://www.amazon.co.uk/Triton-Trimix-Valve-15mm-Approved/dp/B004UKJJ2G.

Plumbed across the hot and cold lines you get regulated thermostat controlled constant temperature water at +/- 2 degrees, which i would have thought was close enough. keeps the electric away from the water as well.
 
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totowroe

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Searching for local stores that carry C-41 chemicals, I found out about Freestyle Photo in Santa Fe Springs, CA. Since that was only 30 minutes from my home, I drove down and bought a 2-liter Unicolor kit.

For my first development I plan on simply using 104 degree hot water in a timely manner. If that's difficult, then I'll look into thermostatic mixing valves like the Triton Trimix (didn't know they even existed!).

Thanks again. You all have been extremely helpful.
 

mts

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The trouble with thermostatic mixing valves is the necessity to maintain a continuous flow. Hot water in pipes cools if you turn off the flow and while the valve will favor the hot flow, it's not hot until water from the tank arrives. I find it easier to set the temperature manually using regular sink valves, and that's good enough and close enough for rinse and wash water. I have a 1/2" plastic hose fitted to the sink outlet and stick a thermometer into its end to set the temperature. For chemical bottles I use the washpan and temperature fall-off method I described above.

Another option for color processing is to live in the tropics with near 100F darkroom temperatures. That may work well in summer, but then you have problems processing B&W chemistry. So shoot color in Summer and B&W in Winter. My darkroom stays near 20C in Winter and about 25C in Summer when I mix the developer for B&W with colder water from the tap. It's not too difficult to wind up with 20C developers for B&W and 100F for color work by simply using cold and hot tap water.
 
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totowroe

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Thanks again for all the help. I'd post links to my results, but I am unable to until I make 5 posts.
 

Dr.Pain-MD

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C-41 developing is easy peasy, not any harder than b&w really. I just use a beer jug of boiling water to bring my chemicals (the developer is the only one that really matters anyways) up to temperature and then it's no different than b&w developing from there.
 

Bob-D659

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Well the third pic looks ok, but you got some weird cross-over going in the first two, a red rubber tire and that red crud around the window. Whats up with that. :smile:
 

postalman

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The first thing that popped into my head when I saw these is "Where the hell are my damned chemicals!!" and a mental fist-shake in the direction of Macodirect. I desperately want to do my first roll of C41 but, well, 3 weeks and no chemicals...

Your success is not helping my lack of patience.

How did you end up approaching the temperature stability problem?

Also as a general question, the thermometers I can find are all +-1C accuracy to match national food preparation standards. I'm sure they are better than that in reality, but I don't know how much. I was looking at a human thermometer (32-42C +-0.1C), but they have slow response times and small measurement surfaces. Can anyone suggest a good thermometer and where to buy?
 
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Mike Wilde

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I have one 'reference thermometer' that rarely comes out of it's case. It is accurate, and yes, also slow. It is also over 2 feet long and goes from -10 to 150F in 1/5 of a degree F increments.
Amazing stuff crawls into your life when you make a habit of scouring liquidation auctions aover a decade when manufacturing, and hence usually also R&D sections are shutting up locally and moving overseas.

All other 'user' thermometers of the mercury(yes, still a few), alcohol, bimetalic dial type, and electronic, all get measured against the reference at 20C and 38 C every year or whenever they get a new battery, or have been dropped.

The deviation from the reference standard is sharpied onto a sticker that gets pasted onto the non-reference thremometer in question.

Then I know for instance, when the thermometer in the c-41/e-6 bath says 38.4 I am really at 38, since the sticker says subtract 0.4C.
 
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totowroe

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I used the electronic thermometer my family uses when we are sick :smile:

1. I poured hot sink water (about 110F) into a big tupperware.

2. I let the checmicals sit in the hot bath until they reached about 105F

3. I cooled the bath to 105F

4. Once the bath and chemicals started to drop in temp, I began the first step of development (soaking the film).

5. I checked the temp in the tub every couple minutes and poured hot water in when it dropped below 102.
 

emjo

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I use a Tetenal C-41 kit. I have trouble with it and as far as I understand there are 2 variables that may still vary... actual temperature and my water.

Keeping the temperature constant is no trouble in the kitchen sink, 10 litres of 45 C water is allowed to cool with the chemicals in bottles. When at 38C [recommended 38-38.5C] I start the 3:15-phase. It takes more than 10 minutes for the temp to cool down to 37C.

But I am unsure if the temp is 38 or, say 40C, etc. The precision is there but accuracy? Must get a better thermometer.

My water might also have a bit too much calcium in it giving a lower pH than it should. Next time I'll get distilled water just too be on the safe side.

Still it is fun and more rewarding than B/W and Rodinal or HC-110.
 
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postalman

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But I am unsure if the temp is 38 or, say 40C, etc. The precision is there but accuracy? Must get a better thermometer.

This is what I'm wondering about. It seems food grade thermometers are +-1.0C or thereabouts accuracy with +-0.1C resolution, whilst medical ones are +-0.1C accuracy and resolution. Unfortunately calibration with ice+water and boiling water @ 1atm only works for the less accurate thermometers that have the larger range (and you're also making some BIG assumptions about the linearity of the response of the cheap $0.01 thermistor they use).

But I'd be willing to trust a $10 medical grade one unless someone tells me not to and just accept the slow response time, because as you say, if you get enough water (I plan to use an insulated tub it has a much slower response time than the thermometer will.

totowroe - Please tell me you mean the same model of thermometer as you give to your family... That may be why they're not feeling well :wink:
 
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