Color processing of every kind requires tight temperature and timing
control.

In other words, NO!

Tetenal makes a room temp C41. Past a certain point you don't want the
film to be outside the process. C41 is a little more forgiving than E6
regarding this but shifted colors are problematic in either scans or  
direct optical prints. I would stay within the suggested guidelines,
also my belief is that the more complex kits give better results over
all.

You can process color negatives (and even E-6) in a stainless steel
tank. I did E-6 once and it worked out just fine. But you must pay
attention to the times and temperatures. I did it just once, in a
photography class in the early 1970s, but it probably would work today.

You use a water bath to maintain the temperature. The first time, you
mix up 100%water and 0% chemicals for each component of the chemistry.
You fill a dishpan or something with hot water somewhat over the process
temperature you must use.

Then when the chemicals are at the right temperature (perhaps 4 degrees
over the desired processing temperature), you run the process and
measure the (first) developer temperature after the development step,
and the fix temperature after the fix (or blix) step. If the developer
temperature is the same number of degrees under the desired process
temper as it was before, you used the correct starting temperature.
If the fix temperature is withing the range specified by the chemistry
manufacturer, all is OK.

You might want to do this a few times to make sure the temperatures are
under control. Then do it with real film and properly mixed chemistry.

It will work, but if you do more than a few rolls a year, you may wish
to get something like a Jobo CPE (or larger) processor. If you do not
need to process many rolls of film, perhaps you should just find a good
color lab.

 Sure. Use a water bath. The Jobo tanks hold temp pretty well and C-41
times are short. The critical one is the developer which is 3:15. Warm the
tank before you start by standing it in the water bath. Add chemicals at the
right temp and you're fine. The rest of the steps have fairly wide temp
ranges. If you use the Jobo tanks on a roller base then you've got agitation
taken care of also. Plug the motorbase into a timer and you've got your
timing looked after.

Nick

Use a kitty litter box or other container that's about 2" lower than
your developing tank.  Something that'll hold 3 or 4 gallons of water.
Use 2 aquarium heaters (100 watt) and an aquarium water pump to heat &
circulate the water.  Temperatures can be held quite accurately with
this.  If the chemistry is supposed to be used at 100 degrees, get the
water to 102.  Put the bottles of chemicals in the container, and your
thermometer in the developer bottle.  When everything's at the right
temperature and stable, hold the film tank in the water for 3 or 4
minutes to warm it, then just follow the processing instructions.

The important thing is to be CONSISTANT.  Do everything EXACTLY the
same way every time and you should get good results.  Your filtration
for prints may be slightly different from someone else's, but there's
no reason you can't get correctly color balanced prints.


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Dave Starr, Senior Shop Rat Emeritus: 14,647 days in a GM plant.
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I use the same tank and reels that I use for B&W. I also use a water bath
for the chemicals to maintain the temp (Using scrap parts from an old
minilab I had sitting around, I made a thermostat controlled water bath. If
you have some old minilabs sitting in your garage, you could probably do the
same!).
Color shifts can be compensated _to a certain extent_, if all the colors
have shifted in the same direction by the same amount. Improper developement
can lead to shifts at different rates in the different colors, and that's
the problem. That said, the process isn't critical; it's fussy.

Ken Hart

It is relatively easy.

I use the same stainless steel tanks and reels I use for B&W.

1.     I load the film onto the reel and place the reel in the steel tank.

2.    I put the chemical containers in a hot water bath to bring them to
temperature.  As another poster noted, only the developer has to be at 100
degrees F.  The others can range from 75 to 105 degrees.

3.     Meanwhile, the film and tank are warmed in a water bath of about 100
degrees.  It need not be precise.  The purpose of this tank is to keep the
chemicals from changing temperature rapidly.

4.     When the developer is 100 degrees (be sure you are measuring temperature
after shaking or stirring the container), I measure it into a heated graduated
cylinder and pour it into the steel tank, which I place in the water bath, and
remove for agitation.

If you make your own C-41 chemicals as I do, the cost is really low and you can
afford to throw out chemistry after a single use.  Do a Google Groups search in
this forum with my name and C-41 and you should find the home brewing formulas.

Have fun!

Francis A. Miniter

i do it in the same paterson tank I use for B&W. I use the Agfa kit for C41
& Paterson kit for E6 - purely because they are readily available. The Agfa
kit allows processing at either 30C or 38C - personally I prefer 30C as the
times are much longer and that temperature is easier to maintain. Quality
was good - colours were nicely saturated and quite accurate when scanned on
a Fuji Frontier (I prefer Fuji superia family films - I found Kodak films
did give slightly off colours but easily correctible). I have only run into
real problems once - I tried to develop one more roll of film than what the
kit was designed for, and ended up with quite dull desaturated negs (could
have partly been cos the film was old too). I have a rectangular mop bucket
that I fill with water about 3-5C above my target temp. I stand my chemicals
in it, with a thermometer in the developer. When the temp of the developer
reaches my target temp, I start developing. During the development process,
I stand the tank in the water bath. The whole process at 30C takes about 25
minutes.
The paterson E6 kit is also easy to use and delivers good results. My only
disaster with this was again when I attempted to use the batch of chemicals
for one more roll than they were designed for. This is only marginally more
demanding than the C41 - there is one extra process compared to C41. This
kit is designed for 38C, and I use the same method of getting temp and
maintaining temp as above.
I actually find it harder to maintain temp for B&W than for colour -
considering my average daytime temps are in the mid 30's, and water comes
out of the tap in the high 20s, it is much easier to maintain a bath at
30-38C than it is to maintain a bath at 20C for B&W. I have plans of
creating a temp controlled bath - one that will allow either cooling or
heating. My plan is to use an electronically controlled thermo switch, and
direct water either through an ice bath for cooling or through a hot water
bath for heating. When the water in the main bath needs it's temp adjusted,
a small submersible pump would be kicked in to direct a little water through
the appropriate bath.

There has been a lot of good advice on maintainig temperature and use
of equipment on hand.

I have to add that a divided color negative developer will make
processing color negatives into child's play.  There was one published
as Patrick Dignan's  Divided C41 color negative developer.  I had been
using my own formulation when Dignan opened a contest for the best
such formula.  After the contest, he patented, or copyrighted, "his"
color negative divided developer.  Since there is really only a
limited way to develop C41 film, his formula and mine (and, I believe,
those of others) are almost identical.  Basically all you do is follow
the principles for almost all true divided developers, in that you
increase the developing agent(s) in the A bath and double the alkali
in the B bath.  Sometimes you split the Sulfite between th two baths
and fiddle with some other control elements.  

I founs it trivial and consistent to treat my divided color developers
as a kind of Diafine for color.  I just got the temp over 75F,
observed the minimum time and agitation and kept things clean.  The
results were just fine from both still camera and reloaded MP film.
They were easily printed by the local 1 hour processor.

Some others in this NG have dabbledwith this.  Sreenath Battaglia,
Jorge Omar and Some Dude may be able to add more recent info.

Robert Vervoordt, MFA

I extracted the heater tubes from a redundant 10" x 8" Nova print
processor, drilled matching holes in a large plastic containor,
inserted the heaters and put aluminum strips above the tubes to
protect them from containers put in the large container. Filled with
water and switched on. Thermostat set to 40c which is just perfect for
processing at 38c and that's it. Works well.
Cheers
Jeff