OK. First of all, by way of background, I'm a competent but still relatively new black and white developer with a hobo darkroom. My enlarger has a dichroic head, and I'd like to start making color prints and possibly developing color negs in my darkroom. I've never done color before, though I'll be taking a class through the local community college in the fall. Problem is, I live a good hour away from the college and I want to do most of my processing at home (I never have enough lab time). I've done it successfully with black and white and now want to give color a shot.
I'm also interested if any of you out there mix your own chemistry from raw materials. I presume this would give me greater longevity of my materials and allow me to mix just what I need for a given darkroom session, assuring the freshness of the solution. It would also presumably be more cost effective than premixed solutions and give me greater flexibility and control over the development process. There are certainly downfalls though, including the up front costs of equipment and learning the more manual process. If any of you have thoughts on this option and how viable it is, I'd appreciate it.
I hear a lot of folks are using the Jobo processors. For film, it seems fairly straight forward - a temperature controlled bath and timed agitation of the canister. For prints, I'm a little confused. It seems you can only have one print in the tube at a time (this much is straight forward). However, I also read on Jobo's site that the tube must be completely dry before loading another print. This seems like it would be excruciating if working with test prints/proof prints or any kind of prints in quantity. It also seems to auto dump the chemistry after use. Doesn't this oxidize it? What if you want to reuse/replenish the chemistry? If those of you who use a jobo print processor could comment on how your process works, I'd appreciate it.
Lastly, I'd like to consider temperature control. I've heard pros and cons about using room temperature chemistry vs standard RA4 chemistry. Again, the jobo processor would resolve this issue. However, for those who use trays for prints or just use a hand tank for film, how do you resolve the temperature issue? Do you fill your entire sink with a temperature controlled bath? If so how do you control the temp? How concerned do I have to be with "hot spots" near the heating element and temperature fall off the further I get from the heating element? What parts of the chemistry do I need to keep hot - just the developer or does everything need to be at a constant temp?
Thanks for taking the time to read this rather long post. And thanks for such an AWESOME site! There's a TON of info out here I can't find anywhere else!!!
I've used a Jobo for both color film and RA4 prints.
Based on the cost of chemicals, I don't think you'll get much price advantage developing your own film. In color there are no real time customizations as in B&W; it's a straight 3 min 15 sec. you're better off having a good lab do this.
Using a Jobo for prints is a pain in the ass. I only use it when I print 16x20s - minimal chemical amounts and good results. 8x10s, and 11x14s, I use a tray with Tetenal room temperature chemicals, while wearing gloves. This provides much better throughput for iterative filter/exposure changes and results are excellent. Tetenal gives you a range of room temps to use (maybe 65F to 75F) so within that range no water bath would be necessary. When done for the day, I pour the solutions from tray to bottle via funnel and reuse until I reach capacity (about 20- 30 8x10 prints per liter).
Jobos can either use chemicals as a one shot or replenished. replenished I dump 1/3 of the old solution and replace with new, e.g., 240 ml of developer, dump out 80ml of used solution and refill with fresh solution to the 240 mark. I have 3 print drums which helps with the drying out between use part.
If you plan to do only 8x10s you might consider a Nova slot processor. it has a thermostat and uses the regular RA4 chemicals which are muchy cheaper than the room temp versions, while giving you the same throughput as a tray.
you'll find that color expenditures are different from black and white. Color paper is much cheaper and color chemicals are much more expensive. this might help you decide which parts of the process you want to do yourself.
Here's my take on your questons (please keep in mind that while I have done some home RA4 I mostly do R3):
Originally Posted by dweccl
Oxidation when pouring the chemicals out of the tube: it undoubtedly does oxidize the developers, but I just replentish 25% above schedule and it seems to work fine. Except for the blix. It needs oxygen.
Temperature control is most exacting when developing film, as there is no coming back from a mistake there; you can always reprint paper.
With RA4 the developer tine is very short (a minute) so I've always had a bigger problem with getting the timing right than getting the temperature right.
Tubes don't need to be completely dry, just dry enough to get the print in. If the tube is very wet it will stick, and if there is liquid pooled at the bottom you might affect the development of the paper that has been wetted longer, especially if you are not wetting the paper very long before adding the developer.
Anyway, here is my page on color chemistries: http://wilson.dynu.net/chemistries.asp
I have been processing C-41, E-6, and RA-4 prints for a while now.
A few comments:
1. I really don't think processing time and temperature is as critical as some believe. I have, in the course of human events, introduced unusual times AND temperatures (try processing C-41 at 35 degrees C - RA-4 printing temperature - instead to the prescribed 38 degrees +/- 0.5 degrees as specified by Tetenal) with nothing like significant effect.
2. "Economy" is not the driving force in my decision to process my own. What is important to me in fairly equal "grades" of importance, is the protection of the privacy of the models - and MY work - I don't want some High School part time kid with nearly out-of-control hormones printing some of the more "indelicate" work that occasionally occurs - and distributing copies far and wide.
3.Quality. I find it easy to exceed the sheer quiality of the best commercial labs. I do *everything* "one-shot" - and, IMHO, nothing can equal fresh chemicals. No commercial labs will do that ... just NOT financially viable for them.... but it is for me.
4. Flexibility. There is as much, if not more, in color processing as there is in black and white. C-41 color negative -and E-6 transparency can be "pushed" and more rarely, "pulled" by altering development times. Color balance in printing can be "fine tuned" - I have a ColorStar channel set up for fair caucasian skin - something that *can* be done in a commercial lab - but not without a lot of hassle ... they *much* prefer "standard" dichro balances. Dodging, burning - even for the more adventurous - "color dodging" are all available.
4. Printing color with JOBO tanks. I've read a number of replies saying, "The necessity of washing the tank and waiting for ti to be *completely* dry before printing again makes JOBO processing impractical."
I've just finished a run of some sixty (60) 8' x 10" Ilfocolor prints. Separate "washing" was NOT necessary ... the 6 x 30 second washing cycle is sufficient to clean tank itself. Drying is done "high tech" - just wipe out the inside of the tank with a wad of paper towels..
THat's about it... I hope to enter this message before I go "over time" and it disappears into bit heaven.
Ed Sukach, FFP.
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Thanks to all of you who responded so far. This is great stuff.
Ed - to respond to your second point, economy isn't the reason I'm interested in mixing my own chemistry either. I see it as a fortunate by product of mixing your own chemistry and having the freshness of the solution and control of the process. Privacy isn't as much of a concern for me, as I don't typically do nudes (yet), though it is an issue I had not considered that I'll remember if the need arises.
In my black and white film developing work, I've always used the developer one shot as well since, in my opinion, the quality and consistency of the results suffers from replenished chemistry. I would, however, reuse the fixer since it was easy enough to check for that "milky consistency" in daylight as it just began to weaken. At that point, I'd just fix a little longer and then dump the fixer I was using. This was more economical while not compromising the quality of the resulting negative.
Most of my questions have been addressed extremely well by the responses so far, though I'd always welcome additional feedback. And while I'd like to at least try mixing my own chemistry, I'm unsure how to do it. I've been scouring the web for information on formulas for RA4, C-41, etc and haven't found any, let alone the general processes for preparation. I did read somewhere that you have to account for the PH balance of your water, but have no idea how to do that. If anyone knows a good reference web site/book for color chemistry, how to prepare, store and dispose of it, I would be most grateful.
Thanks again to Ed, B.E. Wilson and Tom. This has been most helpful.
I have been processing color for many years using scratch mix chemistry. The complicated tabletop processing units are not necessary, especially for film (E6 and C41). Use a simple waterbath for the solution bottles. I use 1 liter for both E6 and C41 and save the chemistry to exhaustion. I put the bottles (glass and nalgene) into a dishpan and fill it with 150F water. After about 30 mins the temperature drops through the 100F processing point. If I don't get back to the darkroom soon enough, then I add hot water to take the temperature up to about 110F and wait for the swing through 100F.
Don't measure the bath temperature alone to determine processing start time. Put a good color thermometer--one you can read to within a degree--into the developer, or 1st developer for E6, and a second thermometer into the dishpan water. I use a dial thermometer that is calibrated against the color thermometer. Watch out for dial thermometers noting that they are adjustable and have to be calibrated against a good glass-bulb thermometer.
Load your film into Nikkor reels and put the reels into the daylight tank, stainless steel being my preference. When the developer temperature is about 102F, fill the tank and start your timer. After filling the tank, agitate for the usual 15s to dislodge airbells. Thereafter hold the tank 3/4 submerged in the bath water. Invert 3 times for a total of 5 sec every 30 sec during the processing, and pour out the developer back into its storage bottle 15 sec before the end of the processing time.
Fill the tank with stop bath taken from the bottle that was in the dishpan. Once the stop bath is into the tank, you no longer have to worry about accurate temperature control. Only the developer (first and second for E6) are temperature critical. The fix and bleach, or blix, depending on your preferred formula process to completion and 90-100F temperature range is fine for these solutions.
Processing is a snap once you achieve a certain level of good procedure and you follow it each time you process. I find that 1-liter of C41 is good for 6-8 or more rolls of film and that it's lifetime in sealed glass bottles is about 2 weeks. Ditto for E6, and note that the fixer, bleach, and stop baths can be used for a couple of batches. You need only to remix fresh developers most of the time.
Mixed from scratch, the chemistry for C41 is under $5.00 for 1-liter, and for E-6 the cost is a buck or so higher. The downside is that you need a substantial chemistry stock and this represents a significant investment if you are starting out with nothing. The upside is that you mix all your own black & white chemistry too, and have the ability to mix what you need when you need it. Suppliers are getting to be more difficult to locate but there are some remaining in the business who don't charge excessively high prices. Be sure to do some shopping for your bulk chemical stock, and try to buy in quantities that are appropriate for 50 batches or more. My collection of chem stock has accumulated over about 30 years. These components, for the most part, have indefinite shelf life.
You will also need a good accurate (0.1g) scale, a triple beam balance does well. You need a reasonably accurate pH meter too (0.1 pH unit), and buffer solution to calibrate the meter near pH 10.0.
Developing good technique and maintaining consistent practice is most important. Color formulae are mostly in the public domain now. I am happy to send you my formulary if you mail me with your address.
M. T. Sandford