How much do you get out of Kodak Flexicolor?

Mr Bill said:

If you give it a go you might want to start out by shooting off a full roll of a standard scene as a reference. If you periodically clip off a couple inches and process, you can visually compare to the first sample.

Click to expand...

Sort of a "poor man's control strip." Yeah, makes sense. The only 35mm color film I have on hand at this time, however, is 10+ year expired. Still, it's long term consistency of the developer we're concerned with -- as long as it stays the same, it's good.

I don't know if this is of any help, but a simple Fuji rule of thumb I used (with minilab film processor) was that you would need to replenish the volume of your developer tank every 30 days. This was using Fuji CN16S NC1 chemical rep cartridges.
So for example, if the machine dev tank was 10L and your rep rate per film was 25ml per 35mm film, then you would need to process 400 35mm films in 30 days to keep your dev tank ticking over.

From my (limited) understanding, the entire point of Kodak's LORR color developer (starter and replenisher) is to be able to keep a line in balance at much lower replenishment and processing rates than 400 films a month. I hope to learn, over the remainder of the year, whether it will stay in balance at two to six rolls a month with the tank solutions stored in airtight bottles at room temp rather than at process temp, open to air. If it will, the cost per film will be similar to using one-shot commercial B&W developers (as opposed to home-mixed or replenished B&W, which can be cheaper than the milk in your tea).

Datasheet replenishment rates are for minilabs or labs equipments that process film in much larger tanks with much more chemistry (a dip & dunk commercial tank can have more than 50 liters inside). With a rotary processor like a Jobo the rate of film surface Vs chemistry volume is so much higher than replenishment is very difficult to make it work with certainty (I can process sometimes up to six tanks with six 120 rolls each in a single session). Continous aeration during rotation is also a drawback.

I tried replenishment using RA-4 chemistry where it is very easy to evaluate the results. It was a 30x40 mm print in a Jobo 2840 drum (120 ml of minimum volume) and a CPP3 using 250 ml of chemistry. Developer had full strength only once, second development was clearly weaker. I tried to replenish as much as 50 ml (9 ml was the rate according to manufacturer specs) and it didn't work. After the second development the results were more or less stable for another 3-4 developments and then started to get weaker again, but the thing is that I liked the first development with full stregth... It would need much more replenishment (about half or more) or use much more chemistry (700-1000 ml). In any case, I decided to go back to one shot use of 120-130 ml and I have perfect repeatability during a session.

A Paterson tank with hand inversion, with a 1L or 2L tank solution storage, will be in a middle ground between a mini-lab processor (5L? 10L?) and a Jobo (one-shot is recommended for good reason). I'll use a minimum of 250 ml for each roll (two rolls of 120 on a single reel need 500 ml to cover), vs. your usage of just over half that amount. Further, my inversion is intermittent, so the developer gets aerated less (and less than a liter of air is trapped in the tank by the inversion cap, limiting the amount of oxygen available to the developer, vs. a Jobo which has the fill/drain path open at all times in rotary processing).

I get to see the histogram for every negative during my scanning (printing is coming, but not yet ready), so I'll be able to tell if the process gets weaker or stronger over time, and adjust replenishment -- or abandon replenishment and return to "reuse by capacity" at eight films per liter (possibly with "used up" developer reserved for XP2) if I don't like the way replenishment runs.

halfaman said:

Datasheet replenishment rates are for minilabs or labs equipments that process film in much larger tanks with much more chemistry...

Click to expand...

Well, it's probably true that all of the trade trials, etc., were done on higher-volume machines, but in principle everything should scale down just fine. EXCEPT for the cases of oxidation and evaporation. As you point out the Jobo processor is gonna really aggravate the oxidation, at least. Which is why, I imagine, that Kodak, in the Z131 process manual, says do not reuse the developer in a rotary processor (such as Jobo). I'm pretty confident that small-volume systems would work fine with replenishment IF oxidation and evaporation are kept to small amounts.

Donald Qualls said:

I'll use a minimum of 250 ml for each roll (two rolls of 120 on a single reel need 500 ml to cover), vs. your usage of just over half that amount. Further, my inversion is intermittent, so the developer gets aerated less (and less than a liter of air is trapped in the tank by the inversion cap, limiting the amount of oxygen available to the developer...

Click to expand...

Uh oh, I had no idea that a Paterson tank would contain so much air. If you're using 500 ml of developer with a full liter of air above it I'm skeptical that replenishment is gonna be successful beyond 2 or 3 processing runs. Based on some estimates I made a few weeks back, that 2:1 air/developer volume is gonna contain nearly enough oxygen to kill it off. (I'm presuming that the rate of oxidation is slow enough to withstand several process cycles before the developer becomes badly hurt.) Keep in mind that I'm largely guessing, but if I had to make a bet...

If you had a Nikor tank, or something else with minimal air volume, I'd recommend running the initial replenishment tests with that. (Or if you have a way to preload the tank with an inert gas.) Once you establish that it works (which I expect that it would) then a switch to the Paterson tank system might be more telling.

If oxidation is the main problem (I'd bet a lot of $$ that it is) then you won't be able to counteract this with replenisher. The replenisher formulation is mainly intended to replace the CD4 consumed in development. An oxidized developer also needs the preservatives replaced. So things are likely gonna be unbalanced unless you heavily "spike" the developer, including starter solution, which basically defeats the benefit of replenishment.

Best of luck with the trial.

So why not fill the Paterson tank with developer? Instead of just covering the film. Then you don’t have to deal with the oxidation issue.

btaylor said:

So why not fill the Paterson tank with developer? Instead of just covering the film. Then you don’t have to deal with the oxidation issue.

Click to expand...

And replenish.

btaylor said:

So why not fill the Paterson tank with developer? Instead of just covering the film. Then you don’t have to deal with the oxidation issue.

Click to expand...

I know nothing about the Paterson tanks, so I was presuming that somehow the inversion cap itself was responsible for trapping the liter of air. But if it's just as simple as filling the tank, well, that's the obvious answer. As long as the airspace over the developer is a small proportion then replenishment ought to work fine. I would expect so, anyway.

MattKing said:

And replenish.

Click to expand...

Well, yea. Thanks for that clarification...

Mr Bill said:

I know nothing about the Paterson tanks, so I was presuming that somehow the inversion cap itself was responsible for trapping the liter of air. But if it's just as simple as filling the tank, well, that's the obvious answer. As long as the airspace over the developer is a small proportion then replenishment ought to work fine.

Click to expand...

This inspired a quick experiment.
Using a three reel Paterson Super System 4 tank, with the central core installed but no reels (to save having to dry them), one litre of water fills right up to very near the top of the light-proof cavity. The airspace above the cavity (where the inverted developer flows into) holds a further 400 ml of water before one needs the inversion cap to stop it from over-flowing into the sink. Based on an eyeball estimate, I would estimate that there is a further 100-200 ml of airspace above the water at that time.
So without reels and film, one litre of developer plus 500 - 600 ml of air above it.
With reels and film displacing some of that developer up into the airspace, I would expect the air above the developer would be down to 400-500 ml.
So one litre of developer and ~500 ml of air above it.
The determination of how much air/developer inter-mixing happens is probably worth at least a masters thesis - the channel through which the fluid flows is quite constricted, and the turbulence would be complex. And that submerged, narrow channel would require another very complex determination if one used the full Paterson tank with continuous rotary agitation.

Mr Bill said:

Uh oh, I had no idea that a Paterson tank would contain so much air. If you're using 500 ml of developer with a full liter of air above it I'm skeptical that replenishment is gonna be successful beyond 2 or 3 processing runs. Based on some estimates I made a few weeks back, that 2:1 air/developer volume is gonna contain nearly enough oxygen to kill it off. (I'm presuming that the rate of oxidation is slow enough to withstand several process cycles before the developer becomes badly hurt.) Keep in mind that I'm largely guessing, but if I had to make a bet...

Click to expand...

I was wild guessing on the volume. See below for a tested answer -- still with some uncertainty, but better than my guess. BTW, I've been using my Paterson with Xtol replenished, used about a liter of replenisher so far (that's 14 rolls, roughly) and there's been no change. neither color change in the developer (aside from a little blue dye picked up from Fomapan when I forgot to prewash) nor change in the negatives. I know color developer has much less preservative than Xtol stock solution, but is oxidation that much worse over a short period?

btaylor said:

So why not fill the Paterson tank with developer? Instead of just covering the film. Then you don’t have to deal with the oxidation issue.

Click to expand...

There's a limit to how much developer will fit and still give inversion action, but it should be "up to the red ring" -- there'll still be enough air inside the inversion cap to ensure the vigorous agitation inversion produces in Paterson tanks. Looks like, for the 3-reel size, we're looking at about 200 ml air to 1400 ml of liquid, best case. However, see below, there may be another way.

MattKing said:

This inspired a quick experiment.
Using a three reel Paterson Super System 4 tank, with the central core installed but no reels (to save having to dry them), one litre of water fills right up to very near the top of the light-proof cavity. The airspace above the cavity (where the inverted developer flows into) holds a further 400 ml of water before one needs the inversion cap to stop it from over-flowing into the sink. Based on an eyeball estimate, I would estimate that there is a further 100-200 ml of airspace above the water at that time.
So without reels and film, one litre of developer plus 500 - 600 ml of air above it.
With reels and film displacing some of that developer up into the airspace, I would expect the air above the developer would be down to 400-500 ml.
So one litre of developer and ~500 ml of air above it.
The determination of how much air/developer inter-mixing happens is probably worth at least a masters thesis - the channel through which the fluid flows is quite constricted, and the turbulence would be complex. And that submerged, narrow channel would require another very complex determination if one used the full Paterson tank with continuous rotary agitation.

Click to expand...

Numbers on the relative volumes are helpful. Roundly 100-150 ml of unavoidable air space relative to 1300-1400 ml of developer, but I think there may be a better way.

We always talk about inversion, and that's how I've agitated ever since I got my first stainless tank, but the first time I ever developed film, and several months later when I first developed unsupervised (still age ten), I had a tank that could not be inverted without just pouring the contents out -- an old FR tank, as I recall, same design as the Yankee adjustable tanks from the 1950s to 1970s. Those tanks used a "swizzle stick" of one sort or another -- either a knurled extension on the top of the reel core or an insert (often a thermometer in an oval housing) that mated with an oval or spline inside the core, to twist the reel and film back and forth in the more or less stationary solution. This produced perfectly fine negatives back then, and my Yankee Agitank, (which I agitate by either sliding the tank fairly sharply left and right along the counter (with the long side facing me) or by tilting on the narrow leg base so alternating edges contact the work surface) also gives good results (at least with B&W film and chemistry -- haven't ever used sheet film in color emulsion).

The Paterson also includes a "swizzle stick" -- and while the one for my older 2-reel tank has long since been lost, my 3-reel tank was purchased new just a few weeks ago and the swizzle stick is safe in the drawer under my darkroom counter.

If I use the swizzle stick to agitate, the solution doesn't get aggressively mixed with air bubbles, it's only in contact with air at a relatively calm surface, and there's no impetus for that air to turn over and present fresh oxygen to the interface. Yes, nitrogen is lighter than air (barely), but density difference on this kind of scale ought to be safe to ignore over three and a quarter minutes. Convection can likely also be ignored over this kind of time frame, both because the design of the tank limits convection to going both in and out through the outer edge (the "pour out" area" -- the "pour in" funnel is inside the core and that's submerged) and because there isn't enough temperature differential (no worse than about 35F) to produce a very strong density variation. I'm neither a fluid interface physicist, nor a photo chemist or organic chemist, but it seems to me that oxidation during a development cycle with "swizzle stick" agitation ought to be at least an order of magnitude less than it would be during the same cycle (time, temperature, and frequency/length of agitation) with inversion.

I would agree that not inverting the tank would certainly reduce oxidation. I have never used inversion as an agitation method anyway- probably because my tanks always leaked! “Swizzle stick” and/or rocking a tank always worked for me.

I should know in a few weeks, then; I've got a big backlog of C-41 to develop, so I ought to be able to tell whether replenishment is working by end of October at the latest.

Another advantage of swizzle stick agitation -- the tank can stand in the tempering bath while I agitate, so temperature will stay steadier. Didn't get my chemicals mixed today (who knew and oil change and tire rotation would take five hours?), so I'll do that tomorrow, and may be able to process the first tank of film in the new chems tomorrow afternoon/evening (Monday evening, if not tomorrow). Then it's all up to the chemistry.

MattKing said:

Based on an eyeball estimate, I would estimate that there is a further 100-200 ml of airspace above the water at that time.
So without reels and film, one litre of developer plus 500 - 600 ml of air above it.

Click to expand...

Again, I have no familiarity with the Paterson units, but I suspect a more accurate number might be had by submerging both the tank and lid in a tub of water to get a complete "fill." And then compare to the normal operating volume. But offhand I'd guess that this is too much air.

Donald Qualls said:

Looks like, for the 3-reel size, we're looking at about 200 ml air to 1400 ml of liquid, best case

Click to expand...

My gut feeling is that this is getting into a usable range for long-term replenishment. But I haven't tried to estimate any numbers, so it's just a really wild guess. The ultimate test would be to see if it works adequately.

As a note, (stable) replenished systems always try to find their way, eventually, to some equilibrium state. Which ideally, in this case, meets the same chemical specs as a fresh mix. But because of the ongoing "extra" oxidation I don't think it will be the same. I'd guess that you'll end up with the developing agent, CD4, being a bit overconcentrated with respect to the preservatives, sulfite and HAS. But the bottom line is that you almost have to do the trial to know if it works ok.

Fwiw someone with a severe interest in this sort of thing could probably design a custom replenisher formulation for such tanks. But they'd probably wanna have at least some basic "wet lab" analytic capabilities. The Kodak H24 motion picture manual gives some such analytic methods (see section 3) for anyone nutty enough to get into this.

I think your swizzle stick option would be really helpful with respect to reducing oxidation. I would wonder if the agitation is adequate, but again, everything I'm saying is mainly guesswork. Good luck, I'll be curious to hear how successful your trials are.

Mr Bill said:

Again, I have no familiarity with the Paterson units, but I suspect a more accurate number might be had by submerging both the tank and lid in a tub of water to get a complete "fill." And then compare to the normal operating volume. But offhand I'd guess that this is too much air.

Click to expand...

But then I would have to re-dry my reels!
Those of us who use temporary darkrooms and otherwise multi-purpose spaces have special concerns!

Mr Bill said:

Again, I have no familiarity with the Paterson units, but I suspect a more accurate number might be had by submerging both the tank and lid in a tub of water to get a complete "fill." And then compare to the normal operating volume. But offhand I'd guess that this is too much air.

Click to expand...

This is something I have the space to try, so I'll do so -- should be able to manage it today.

My gut feeling is that this is getting into a usable range for long-term replenishment. But I haven't tried to estimate any numbers, so it's just a really wild guess. The ultimate test would be to see if it works adequately.

Click to expand...

Agreed. We'll know by the end of the year, likely by Thanksgiving, whether it's practical.

I think your swizzle stick option would be really helpful with respect to reducing oxidation. I would wonder if the agitation is adequate, but again, everything I'm saying is mainly guesswork. Good luck, I'll be curious to hear how successful your trials are.

Click to expand...

I've seen video on YouTube of others using swizzle stick for C-41, and haven't seen any complaints in those videos or their comments about poor results. But again, I'll know that after I scan the first few rolls, so likely by next weekend.

Okay, now it begins. I've mixed one liter each of developer tank solution (replenisher, starter, and water), developer replenisher, bleach, and fixer. I already have two liters of mixed Final Rinse that I've been using for both color and B&W. I've recorded on each bottle the relevant requirements or limitations -- best figure I can find for LORR developer replenisher using professional films averages about 34 ml per roll (less for consumer films, a little more for all professional, and my films are about 90% professional -- this can be adjusted as needed); fixer capacity varies from 10 rolls in SM chemistry to a quoted 32 rolls that I found online for the regular Flexicolor; I'll test clearing time periodically. For bleach, again, I'll have to test it periodically, but for now I'm assuming it's similar capacity to the fixer.

Later today (after lunch) I'll load up a tank full of film and then start the tempering bath, and I'll process and replenish and be done by bedtime. No reason to expect anything but "just fine" for the first tank full -- it's later on I have to watch for changes. If this works well for long enough (a couple months, say) without going out of whack, I might spring for a package of control strips (I have a +10 diopter to fit my spotmeter, to use that as a poor man's densitometer). Otherwise, I'll just go back to limited reuse at 8 rolls per liter of tank solution, and then out it goes (or gets reserved for XP2, which isn't anything like as picky as actual color).

@Donald Qualls Just to confirm, you'll do a bunch of rolls replenishing after each one, right? How many rolls are you going to be processing in one setting?

Also:

Donald Qualls said:

Final Rinse that I've been using for both color and B&W

Click to expand...

I was about to ask! By accident, I ordered a lifetime supply of Flexicolor Final Rinse (does anyone need some, BTW?) and I was wondering how different is it from B/W wetting agent like Kodak Photo Flo or Ilford Ilfotol.

Bormental said:

By accident, I ordered a lifetime supply of Flexicolor Final Rinse (does anyone need some, BTW?) and I was wondering how different is it from B/W wetting agent like Kodak Photo Flo or Ilford Ilfotol.

Click to expand...

It is essentially Photoflo with a bactericide.
As developed black and white films contain silver, and as silver itself is a good bactericide, you don't need to add more.
I expect it works out to be more expensive than Photoflo. And it might be more toxic (I don't know) in its concentrated form. But if you already have it .......

I ordered a 50L package for something like $50 thinking "this is expensive" but I missed "x5" in the title, so I am sitting on 250L of it.

Bormental said:

@Donald Qualls Just to confirm, you'll do a bunch of rolls replenishing after each one, right? How many rolls are you going to be processing in one setting?

Click to expand...

I currently have only two reels for my Paterson tank, and while I have four stainless reels and a tank that will hold them all, it takes much too long to fill and drain and is currently shelved. I've just purchased more Paterson compatible reels, they'll be shipping from Texas on Monday, so I should have them by next weekend. At that time, I'll be able to process up to 3x 35mm in a single tank (and have enough reels to run two tanks, total of 5x135 or 6x120, in a short time, with a reel in reserve). Replenishment takes place after each tank is processed -- so tonight, after processing two 24 exposure rolls of ISO 400, I gave 45 ml LORR replenishment. In fact, I'm nearly through my film backlog (only six rolls left, and one of those is 12 exposures), so I need to order some more color film.

I used swizzle stick agitation for everything except the Ilford wash after fixer, before final rinse; the partially used, replenished developer has darkened slightly from the fresh appearance (barely yellower than water clear became obviously yellowish, though still lighter than, say, anything you'd call "tea"). These negatives look perfectly normal -- as they should, this batch is what I'd get if I were one-shotting my developer. The question of developer life will start to be answered in a couple more weekends of processing.

I was about to ask! By accident, I ordered a lifetime supply of Flexicolor Final Rinse (does anyone need some, BTW?) and I was wondering how different is it from B/W wetting agent like Kodak Photo Flo or Ilford Ilfotol.

Click to expand...

I've been using C-41 Final Rinse for my B&W films as well, because I already have it mixed and it seems to keep very well, with only carry-out loss to consider. I mixed mine with RODI water (purer than most distilled) and it does exactly what Photo-Flo should -- ensures no water spots on the film, as well as the preservative effects on color negatives. Unless something in it will react with image silver over a long term, there should be no problem using Final Rinse in place of your usual wetting agent, other than, as noted, the higher expense -- but since you've already got it on hand...

Has anyone broken down the 5l kits into 1l amounts? I dont' really want to mix the whole 5l, just one or two at a time, and was wondering what the volumes were...

Found this. Can anyone confirm?

Developer-
80ml LORR A
40ml LORR B
20ml LORR C
30ml Developer Starter

Patrick Robert James said:

Has anyone broken down the 5l kits into 1l amounts? I dont' really want to mix the whole 5l, just one or two at a time, and was wondering what the volumes were...

Found this. Can anyone confirm?

Developer-
80ml LORR A
40ml LORR B
20ml LORR C
30ml Developer Starter

Click to expand...

https://www.kabbottphoto.com/c-41-with-kodak-flexicolor-at-home/

Patrick Robert James said:

Has anyone broken down the 5l kits into 1l amounts? I dont' really want to mix the whole 5l, just one or two at a time, and was wondering what the volumes were...

Found this. Can anyone confirm?

Developer-
80ml LORR A
40ml LORR B
20ml LORR C
30ml Developer Starter

Click to expand...

What I used yesterday came to less of the B and C than that -- as I recall, it was 22.4 ml B and 11.2 ml C for a liter. A little less for the tank solution, of course -- .763 times as much. FWIW, the volumes are on the bottles, so if you're mixing a liter of replenisher you'd just divide by 5 to get one liter instead of 5.