C-41 Process Temperature control need advise

[luis_modesti]

<p>To control C-41 process temperature, need some advise:<br>

what is better:<br>

A) a Delta 1 Water Temp with lock control and a water container bin . Something like this listed in B&H <a href="http://www.bhphotovideo.com/c/product/15867-REG/Delta_1_65010_Water_Temp_II_with.html">http://www.bhphotovideo.com/c/product/15867-REG/Delta_1_65010_Water_Temp_II_with.html</a><br>

or<br>

B) an electrical used Water Bath from ebay, something like this:<br>

<a href="http://www.ebay.com/itm/170974122328?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649">http://www.ebay.com/itm/170974122328?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649</a></p>

<p>both are approximately the same price, but with no-prior experience with C-41 , I would think the electrical water bath from ebay will be more precise and reliable solution. But I dont want to over-engineer it or spend more than I need if simpler solutions are available. I will be using Kodak Chemicals.</p>

<p>Thanks in advance.</p>

[Alan Marcus]

<p>Let’s look at the tasks. 1. The chemicals in bottles must be adjusted to temperature. 2. The wash water must be adjusted to temperature. Likely you can accomplish without any mechanical aids. The chemical bottles are placed in a plastic tray deep enough and big enough to submerge all, halfway. A thermometer in the tray tells the story. Fill the tray with warm water and add hot or cold water till the desired temperature is achieved. In your favor is the fact that water holds its temperature. In other words it won’t be difficult to adjust and maintain by simply adding a cup or two of hot or cold water.</p>

<p>Now the wash water is a different story. We would like to have a thermostatic valve that automatically maintains a set temperature despite meddling chances in water pressure or incoming water temperatures. While nice, none of these devices are absolutely necessary. You can make do with a thermometer and attention to detail. Adjusting a mixing faucet is doable. You can also run the water in a pitcher and micro-adjust the hot and cold volume to achieve.</p>

<p>Bottomed line is, do it once or twice and then, if you like it, invest in the gadgets.</p>

[thirteenthumbs]

<p>I recently processed several rolls of Seattle Film Works film in Jobo Press Kit chemicals. I warmed the chemicals and processed in a porcelain lined cast iron sink with a 10 quart plastic pail of water on the counter for wash water. I started with water 10°F above the process temperature then lowered the temperature to processing temperature after a few minutes and had no problem with chemical or wash water cool down in a processing session that ran about 40 minutes in a 60°F enviorment. </p>

[Fotohuis RoVo]

If you take a big volume of water the warm capacity will be enough to maintain that 3:15 minutes on 100F/38C.

Alternative Jobo processors: TBE-2, CPE, CPA-2 , CPP-2 or a new CPP-3. The last one is over €2500,- excl. the

necessary drums.

A second hand TBE-2 you can have here in Europe around €50,- . So it is just what you want to spend on money and how

confortable you want to develop.

[ron_taylor3]

<p>1. The delta water temp control does not actually regulate water temp if the image is accurate, product reviews indicate that it is a thermometer with a ball valve only. Mechanical water temp controls use a pair of pistons controlled by a diaphragm to blend hot and cold water such as a powers valve, this is not the beast. <br>

2. The Fischer temp control unit will likely bid higher than the start price, it appears to hold less than a gallon of liquid and still requires a good thermometer to be set accurately.<br>

3. If you have modern faucets with (1/4 turn to full on) the water temp when mixed will be consistent, until the water heater starts refilling.<br>

<br />So..<br>

I agree with the others, get a large tray like a kitty litter tray and a good thermometer which will probably set you back an easy $25.00. Do a dry run just watching the temp of the water drop over time (work in a heated space to minimize temp drop). I have processed hundreds of rolls of E-6 and C-41 without expensive automated temp control.<br>

One other thought about C-41 kits, don't let them sit around more than a couple weeks, I have had severe grain problems with old developers.<br>

<br />Simple will be more rewarding in the long run, take your time and have fun!</p>

<p>Ron Taylor.</p>

<p> </p>

[Mike Howard]

<p>I use a Precision Science model 183 water bath I picked up off ebay for $40. I cannot imagine going back to the kitty litter solution. I have the temps I use marked off on it, pop the bottles in, and in an hour or so have perfect temperature control. It is great for batching, since it will stay a constant temperature all day. There are several of these and others very similar on the Bay right now. Mine holds up to 8 1 liter bottles, great for E-6 or C-41.</p>

[john_enea2]

<p>I use a $20 solution like the one in the link below, a nice 16 quart slow cooker. My process is very similar also with the one explained in the link (it gave me a great idea of where to start!). It keeps the temps just where I want them with no temp swings. give it 30 min to acclimate the chems to the proper temp but once its there it stays dialed in. cheap, easy to clean and consistent results. I bought the glass bottles from my local camera store which has a great darkroom section but they can be found on amazon and i have heard of people getting them from large pharmacies as well, empty prescription bottles or something like that.<br>

<br /> http://www.lamarlamb.com/On-Film/Film-Blog/Developing-Slides/13127177_bK665M#!i=948545069&k=mwgyG</p>

[luis_modesti]

<p>Alan brings an important point I overlooked or just didnt even know. how about the wash part of the process. The temperature must be controlled during wash there too. I will use the pitcher idea. Any other suggestions ? or ideas.<br>

Thanks guys.</p>

[Alan Marcus]

<p>The C-41 Kodak process specifications:<br>

Developer - 3 minutes 15 seconds @ 37.8 ± 0.15 Celsius 100 ± 0,25 Fahrenheit<br>

Bleach - 3 minutes to 4 minutes 20 seconds @ 38 ± 3 Celsius 100 ± 5 Fahrenheit <br>

Wash - 1 minutes to 3 minutes 15 seconds @ 24 to 41 Celsius 75 to 106 Fahrenheit <br>

Fixer - 4 minutes 20 seconds to 8 minutes 30 seconds @ 38 ± 3 Celsius 100 ± 5 Fahrenheit<br>

Wash - 3 minutes 15 minutes 15 seconds @ 24 to 41 Celsius 75 to 106 Fahrenheit<br>

Stabilizer - 1 minute 5 second @ 24 to 41 Celsius 75 to 106 Fahrenheit<br>

Dry 40 to 68 Celsius 104 to 155 Fahrenheit</p>