How do you know if color chemicals are still working properly?

[Fiodor]

How do you know if Kodak Flexicolor chemicals are still working properly? (before processing important negatives)

 

For instance:

 

- Developer (not mixed): I recently posted a thread about D-76 and based on the comments of fellow posters I developed a leader in ambient light to see if it got black at the indicated time. Can I do the same test with color developer? Of course, I could also, apart from this test, process a couple of images. But I like the test because it gives you a good indication before processing any images.

 

- Bleach (not mixed): …?? The color? Another indication?

 

- Fixer (mixed with water): Can the clearing time test be used with color fixer? How is the calculation? I just posted another thread about this.

 

- Final Rinse (not mixed): …?? Is it good for ever?

[Bill C]

How do you know if Kodak Flexicolor chemicals are still working properly? (before processing important negatives)

 

The best test, really, is to process some unimportant negatives. Actually, better would be to use a manufacturer supplied reference strip, a so-called "control strip," but the evaluation calls for a densitometer, as well as knowledge of what the readings mean.

 

Developing an exposed test strip to black is not a reliable test for color film, due to the possibility of a bleach-contaminated developer. This can put a heavy chemical fog on the film, essentially ruining your negs, but could still pass the develop-to-black test. But as a simple test to see if the developer is "dead," development of fogged leader to black could be useful.

 

Regarding bleach, my experience has been with earlier versions. In that case, bleach really only goes "bad" as a result of extended use. For a long time one could keep it going by aerating periodically; eventually one of the components (bromide ion) would be completely used up; at that point the bleach is finished. Now, if you were to replace the missing chemicals and aerate, then the bleach would be fine again. To repeat, my experience was with a former version, but my guess is that the current bleaches behave in a similar manner.

 

The only simple test for bleach is to have to have a spare, "known good" bleach on hand. After normal processing, but with a questionable bleach, you would clip off a sample of the processed film and rebleach it. If the appearance changes after rebleaching then this means that the original bleach was not adequate. In any case, it is always possible to rebleach film at a later time to correct the problem.

 

For fixer, a clearing-time test should be good. But... if the fixer has any cloudiness, or a yellowish precipitate on the bottom, this suggests that the preservative (sulfite) is gone and that the fixing agent is breaking down. In this case, you don't want to use the fixer.

 

Regarding the final rinse, I can't say. (I'd personally look at the MSDS to see what's in it, and make a judgment from that). But off the top of my head, I'd guess that the final rinse would, by far, outlast both the developer and the fixer.

 

As a note, given how forums are nowadays, perhaps I should say that I'm speaking from experience, not from internet research.

[glen_h]

As with black and white fixer, you should be able to rebleach or refix under bleached or under fixed film.

 

And as with black and white, developers can oxidize from air access.

 

Color is an indicator, but not a completely accurate one.

 

I don't remember now the color of new C41 developer, is it completely clear, or slightly colored?

 

In any case, I believe dark color is bad.

 

I believe the developer comes in three parts, and is less sensitive before mixing the parts.

Best is to only mix as much as you can use in a short time.

[Alan Marcus]

There is no way to truly know if the solutions of the process are up to snuff by just making a visual inspection. That being said, all solutions should have the proper color and they should be transparent (light transits). Fluids should not contain copious amounts of floating solids,. Testing the developer by watching a scrap of film darken in room light is wise but not faultless.

 

These developer have an affinity for oxygen and as it oxidizes its potency declines. Solutions contain preservative that mitigate but once these are drained, safeguards are lost.

 

The dyes in the film are organic. Organic things are quick to change as surroundings change. We are talking, temperature and pH (acidity/alkalinity). The dyes blossom when conditions are just right but wither when wrong. Testing the pH is difficult because the solutions are well buffered.

 

The initial process is twostep bleach then fix. Home kits combine for simplicity but some of the robustness is lost.

 

The black & fix test based on double the time to clear, can be useful. Keep in mind, little harm will result if the bleach, fix or blix time is increased.

 

Again, color film developing is highly susceptible to variations in pH. This is because color film has multiple emulsion coats in it takes time for the fluids of the process to infuse. Change the pH and rates alter unpredictably.

 

The best test would be to develop completely a sacrificial strip of film and then check the finished results. You can make these. Shoot a roll of two imaging a colorful subject with “memory” colors. You can do this by adding multiple paint-chips to a shot of a colorful dog toy etc. Set his exposed film aside 72 hours and then freeze. Each time you develop, include a snippet of the frozen test film. Look for variations between chemical usages. This test can save your bacon . The 72 hour delay between exposure and freezing allows most of the latent stuff to occur.

[Fiodor]

Thank you for all the replies. Really great information.

 

I forgot to mention that I ask because I didn’t use the chemicals for a year, and they are all “expired” according to the indications of the bottles.

 

I bought them in 2017, like two years ago. The developer (the three bottles) expired by mid-2018. The fixer expired in November 2017. Bleach in mid-2017 (this was originally bought before the rest of chemicals; I just got a 1 liter bottle from someone).

 

I have the original 2,5 liters can of fixer, and also a 700ml solution I did two years ago mixing it 1:1 with water, as indicated. I used this solution to process 8 rolls, the last one more than a year ago. I think the recommended capacity of a liter of mixer solution 10 rolls. And also Kodak recommends not using a fixer solution for more than eight weeks, but I used the solution in December 2017, long after that limit, and it was okay.

 

Of course, I could mix a new solution of fixer with the original “expired” fixer. I still have a lot!

 

Bleach was never aerated. I mean, only when I opened the bottle to process. So in the last year it has been resting there in a closed bottle.

 

Eight color rolls, that is all I processed. But yesterday…

[Fiodor]

esterday, after reading some of the replies, I processed three images. I used the same solution of fixer and the same non-aerated bleach. As usual, with the help of four syringes (one for water), I prepared 600 ml of developer solution for developing two rolls in my tank. In this case, I used only 300ml and I have the other 300 for other roll.

 

I don’t know. I compared the negative with the first one I developed two years ago, which was the same film (Kodak Colorplus 200). This last roll is a tiny more dense, but I guess this is normal. But also the numbers and words printed are a bit more blurry, not so sharp (is this common?). And the “base fog” is also a bit more dense (is this normal, even in the same model of film?). I don’t have another Colorplus 200 developed by me to compare.

 

Then I scanned the images and from the first preview I saw something strange. One possibility is that the auto-color of the Epson Scan gives a clear tint because there is a strong color of one object in the foreground, and so it compensates. I know this, and usually if this happens, I change the levels, but I am not sure it is only about this. The third images is not very strange, it is a wide shot… I realized that I needed more normal shots, like a park, a green grass and a blue sky (and I feel stupid because I spent like 4 hours to process these three images).

 

My question is : when the chemicals are old, can we expect changes in color, a general tint or some alteration that confuses the scanner software? If this is the case, is it about the developer or… maybe the bleach?

 

Here are the three images as the Epson Scan auto-adjusted, and then a personal adjustment made in the same software and/or Photoshop (I know that the best way to judge a negative would be to see it with one’s own eyes).

 

[Bill C]

My question is : when the chemicals are old, can we expect changes in color, a general tint or some alteration that confuses the scanner software? If this is the case, is it about the developer or… maybe the bleach?

 

Hi, well we don't expect changes strictly from the chemicals being "old," but rather from being out of spec chemically (with respect to the proprietary formulas). But since the user doesn't usually have analytic capabilities, the easiest way for a manufacturer to deal with this is probably to just specify a lifespan. In the case of Kodak, I've seen their recs, over the years, to generally be conservative. Meaning that things are often perfectly usable past the expiration date.

 

Back to your situation... looking at just the "base fog" (typically called "stain" in processing labs), there are two basic ways for it to get too high. The first is for the developer to to actually form excessive dyes - this could be from a developer defect, or even fogged film. The second way is for some (unwanted) silver to be left in the film; normally all the silver is removed by the bleach and/or fixer. The first thing, there's not a simple way to check (outside of process control strips...). The second can be tested by rebleaching and refixing, etc., in "known good" chemicals. If there is any change at all, this means that the original bleach and/or fix were somehow deficient.

 

Here is probably the best way for you to test. Select a negative that you don't need. Use a scissors to cut it in two, cutting through areas of consistent tone. Take one of the pieces, then rebleach, rinse and refix, etc. After drying, hold it next to the rest of the negative and compare both pieces over a lightbox, or whatever. If the original bleach and fix were ok, there should be no visible change.

 

Note: you normally would want to use a "known good" bleach and fixer, but since yours seem to be at least generally functional then you would expect that if they did not quite finish the job then giving additional time would bring about SOME change.

 

If you DO see a change, you won't know if it's the bleach or fixer to blame. You could repeat the test but refix only. If this shows a change then you know the fixer is a problem. If there is no change on refixing, only, then the problem would seem to have been with the bleach.

 

BTW, one way to aerate small amounts of bleach are to put it into a much larger jar then shake vigorously. Best of luck with your process.

[Fiodor]

@Bill C , thank you very much.

 

Do you think an orange tint could be caused by a defective process? Can a defective developer provoke such a color alteration?

 

In principle, I have the impression that there is a mild orange tint. Should the negative look cyan or something? Well, I don’t see that.

 

I could do the test you suggested. Should this half frame be immersed in a glass or something with just enough liquid to cover it? O should I process in the tank with 300 ml?

 

Based in your description, I guess I can’t bleach without fixing and then washing and then applying final rinse. I mean, I can’t do any step without doing the following ones, can I?

[Bill C]

I could do the test you suggested. Should this half frame be immersed in a glass or something with just enough liquid to cover it?

 

Hi, you're welcome. I'd just use something like a small beaker or a disposable plastic cup or something like that, with enough liquid that lets you wiggle the film around freely (gloves are a really good idea if you do it by hand). But just about anything works. None of the details are too important. Basically you just have some film that ideally has been completely bleached and fixed, and thus should be immune to further changes. So if further bleaching and fixing show ANY change then it is apparent that the initial treatment was not complete.

 

Based in your description, I guess I can’t bleach without fixing and then washing and then applying final rinse. I mean, I can’t do any step without doing the following ones, can I?

 

Right. If you're gonna keep the film, that is. Personally I'd probably be throwing away the re-treated strip, so I'd probably just wash enough to get it visually clean, then dry for the comparison.

 

You DO always need to fix after the bleaching, though.

 

Regarding color of the "blank" film, the orangish color is inherent in the film; it's the color of certain unreacted dye couplers. I'm doubtful that it can be changed much, but can't really say what the extent of color changes would be. I've never really paid that much attention; my experience has been more along the line of heading off problems before they can cause a noticeable effect.

[glen_h]

 

(snip)

 

Back to your situation... looking at just the "base fog" (typically called "stain" in processing labs), there are two basic ways for it to get too high. The first is for the developer to to actually form excessive dyes - this could be from a developer defect, or even fogged film. The second way is for some (unwanted) silver to be left in the film; normally all the silver is removed by the bleach and/or fixer. The first thing, there's not a simple way to check (outside of process control strips...). The second can be tested by rebleaching and refixing, etc., in "known good" chemicals. If there is any change at all, this means that the original bleach and/or fix were somehow deficient.

 

(snip)

 

 

I have had ordinary black and white rapid fixer silver plate bottles way before the appropriate number of rolls.

 

As I understand it, this is due to pH change. If one has a pH meter, and adjusts to keep it in range,

it is supposed to last. I suspect C41 fixer could have the same problem. Concentrate in closed bottles

should last a reasonable time, but mixed doesn't last as long.

 

Well, also, I often used it with Diafine, which recommends a water rinse instead of acid stop bath,

which means more pH change for the fixer.

[Fiodor]

@Bill C I did it.

 

When it dries, I will observe it side-by-side with the other piece. And also I will scan the two pieces together and post the image.

 

When I said I think the image is orangish, I meant the positive, the final image. So in that case the negative would be bluish or something, but I don’t notice that at first sight. I think the Epson Scan software would automatically show white walls as white, so I don’t understand quite well. I think there is something strange, but I may be wrong.

[kmac]

Here are the three images as the Epson Scan auto-adjusted, and then a personal adjustment made in the same software and/or Photoshop (I know that the best way to judge a negative would be to see it with one’s own eyes).

 

Your "personally" adjusted images look ok. Rarely is a color negative perfect. Post processing is nearly always needed to improve color and contrast. You seemed to have done alright with that

 

For the age and/or potency of chemicals, a wise method is Alan Marcus's of completely developing a sacrificial film or part film and check the results. I use this method now but it's important to get the temperatures and times right just as you would developing a film you want to keep. In the past I've been a bit haphazzard developing test strips, which only defeated the purpose of doing the tests

 

I've also come to realize that fooling around with old chemicals is a waste of time and an embarrassing waste of money. Accumulating exposed films for freshly mixed chemicals and developing the films within a week or two is more cost effective and ensures the chemicals are doing their job effectively as they were designed to do, provided the instructions are strictly adhered to. Even then the negatives may have a slight color cast, but that's why we have adjustments in scanning and external editing softwares. It's pretty inevitable that some post processing needs to be done

[Fiodor]

Following Biil C's instructions, I rebleached and refixed a half-frame. I don’t notice any difference. I used the same chemicals (the liter of bleach never aerated and the old solution of fixer). I applied 6:30 minutes each of them. So the film is apparently well bleached and fixed.

 

Also, I realized that the orange veil that I see in the scans is eliminated more simply not adjusting individual color levels, but merely increasing the general (RGB) black input level on the Epson Scan. In general, just moving this adjustment a few points, I mean 5 o 10 points, doesn’t imply having an orange tint or not, as far as I remember. I don’t know if this is related to the alleged denser “base fog”, which is only subtle.

 

Considering all this, I may say that, apparently, the three images were successfully processed. I still have doubts with the “base fog” and the sharpness of the numbers written in the border of the film (I don’t know how they call them in English).

 

And I think I could process a new roll without major fear.

 

I learned a lot, so again thank you for the contribution to the thread.

 

Here is a scan of the rebleached and refixed piece side-by-side with the original piece. And then the same composition but with 10 or so less points of black input, letting the orange veil be visible.

 

[Fiodor]

Accumulating exposed films for freshly mixed chemicals and developing the films within a week or two is more cost effective and ensures the chemicals are doing their job effectively

 

How much time could you leave an exposed film in the refrigerator? I read somewhere that color film is less resistant than B&W in this sense. And also, that if you underexpose a film with the intention of overdeveloping (pushing), the images are more prone to be altered. So keeping an underexposed color film would be especially risky. At least this is what I read somewhere, in a forum, article or something. I have had an underexposed color film in my refrigerator for two months, is this too much?

[Fiodor]

The best test would be to develop completely a sacrificial strip of film and then check the finished results. You can make these. Shoot a roll of two imaging a colorful subject with “memory” colors. You can do this by adding multiple paint-chips to a shot of a colorful dog toy etc. Set his exposed film aside 72 hours and then freeze. Each time you develop, include a snippet of the frozen test film. Look for variations between chemical usages. This test can save your bacon . The 72 hour delay between exposure and freezing allows most of the latent stuff to occur.

 

Do you mean exposing the 36 shots of a roll with the same image? I mean, shooting 36 times the same still subject? And then developing a piece of it (difficult to cut exactly a frame) every time you develop a new roll?

[Alan Marcus]

Test film is sacrificial film. You shoot the same subject 36 times. You allow for latent image shifting by ageing the exposed film and then freezing it. Cut off a snippet and then develop it. It makes no difference if this snippet is properly cut. All you care about, is does the developed image on the snippet look OK? If false, discard the solutions. If true, OK to process another roll.

[kmac]

How much time could you leave an exposed film in the refrigerator? I read somewhere that color film is less resistant than B&W in this sense. And also, that if you underexpose a film with the intention of overdeveloping (pushing), the images are more prone to be altered

 

The longest I've left an exposed color film in the refrigerator (frozen), before developing, was 12 months. In freshly mixed chemicals, the film developed great and the images required very little post processing

 

This is a cropped image from that 12months frozen film. No post processing has been done except for a hurried blanking out of the license number

 

I'm learning from Alan now that a 72 hour period is needed for the exposed emulsions to naturally "adjust" before freezing the film. If my memory serves me correctly, this film did lie around under my sink for some time before I finally froze it, because I wasn't ready to mix the chemicals at that point

 

I've never "pushed" a color film so I can't advise on that but I think 15-30secs extra time is the absolute limit

[Fiodor]

Test film is sacrificial film. You shoot the same subject 36 times. You allow for latent image shifting by ageing the exposed film and then freezing it. Cut off a snippet and then develop it. It makes no difference if this snippet is properly cut. All you care about, is does the developed image on the snippet look OK? If false, discard the solutions. If true, OK to process another roll.

 

Okay. How much time before processing or manipulating the film should you take the roll out of the freezer?

[kmac]

Okay. How much time before processing or manipulating the film should you take the roll out of the freezer?

 

Do you mean the time it takes to warm the film after removing it from the freezer?

 

Let it warm for several hours before processing

[Alan Marcus]

Frozen test film is handled in total darkness. You cut off a snippet and place it in a lighttight container. The roll of test film is immediately returned to the freezer. The snippet can be processed immediately. The only danger is the formation of water droplets on the film due to condensation. Since this is a test film, we don't care if water droplets form. The frozen film warms up so quickly, it won't be a factor. In other words, process the test film without regard to its temperature.