Kodak Gold 200 & Adox C41 kit - help with troubleshooting heavy colour casts

[albireo]

Understood - but it seems to me that the base colour might be a symptom that is inherent in the film, not your process.

But Matt I thought people had chimed in saying the difference between my self-developed sample and my 'reference' was far too wide to be accounted purely by support/batch variation?

In any case, I should be able to clarify this once and for all soon, as I am now tracking+controlling for Gold 200 batch numbers.

 

[koraks]

I will develop one myself with the Adox C41 kit.

With an added stop bath after developer, I assume?

You're right that @vwalt's example is a little biased towards cyan; I see it too. Bumping the red channel a bit yields what I experience as a more neutral/natural result. But I'd pre-emptively caution against complicating an effort to obtain good negatives with discussions about filtration/color balancing in printing or digital post processing.

 

[vwalt]

Thanks Walt - these things are of course personal preference and monitors etc play a role here, but do you notice a small cyan or perhaps greenish dominant in your example? Again, perhaps just personal preference or the impact of seeing this on my own monitor.

You're very right!

I'm struggling with this because I use two different monitors, one at work and my laptop at home. Both are calibrated but the curves are clearly different. On my laptop colours are as I want them. At work I get the greenish dominance.

Assuming that most viewers of the image will have uncalibrated screens complicates matters and I'm pondering how I might solve this conundrum and perhaps someone has advice for me?

As a start, I probably need to standardise on the calibration hardware which is different. On the laptop I use a Calibrite HL display Pro, at work the monitor uses the Eizo built in calibrator and that is surely to give differences. Of course the ambient light is different at both locations.

As you can no doubt surmise, I have a lot to learn about monitor calibration!

 

[koraks]

Assuming that most viewers of the image will have uncalibrated screens complicates matters and I'm pondering how I might solve this conundrum and perhaps someone has advice for me?

There's not all that much you can do, really. Displays just differ, and if that's not enough, viewing conditions are wildly different as well and this in turn impacts how we experience/see colors - which of course is subject to considerable individual variety to begin with. So it's basically a gigantic crapshoot.

In terms of calibration, if you get very different colors on two monitors, evidently, something didn't work out w.r.t. calibration, and/or either of the monitors are just relatively poor quality-wise. I have two calibrated monitors of different brands & types next to each other and they show fairly subtle differences. This is normal and virtually unavoidable. However, the clear cyan bias in your image combined with your remark that it looks good on one screen makes me suspicious of the successful calibration and/or quality of that screen.

However, if you want to explore this further, I'd suggest doing this in a separate thread. I think @albireo is trying to optimize his C41 development routine and as I stated above, it's not wise to contaminate that process with digital color balancing parameters. That's a different universe.

 

[vwalt]

There's not all that much you can do, really. Displays just differ, and if that's not enough, viewing conditions are wildly different as well and this in turn impacts how we experience/see colors - which of course is subject to considerable individual variety to begin with. So it's basically a gigantic crapshoot.

In terms of calibration, if you get very different colors on two monitors, evidently, something didn't work out w.r.t. calibration, and/or either of the monitors are just relatively poor quality-wise. I have two calibrated monitors of different brands & types next to each other and they show fairly subtle differences. This is normal and virtually unavoidable. However, the clear cyan bias in your image combined with your remark that it looks good on one screen makes me suspicious of the successful calibration and/or quality of that screen.

However, if you want to explore this further, I'd suggest doing this in a separate thread. I think @albireo is trying to optimize his C41 development routine and as I stated above, it's not wise to contaminate that process with digital color balancing parameters. That's a different universe.

Thanks Koraks

Noted re calibration of monitors. My lips are sealed

 

[albireo]

With an added stop bath after developer, I assume?

Well I have some citric-acid based B&W film stop bath - would it work? Sadly I don't have any acetic acid. Else I'll skip the stop and pour the blix in directly. But no intermediate water bath for sure.

 

[koraks]

Citric acid should work, although @Photo Engineer/Ron Mowrey was always adamant that citric acid should not be used in a color process.
Cleaning vinegar is not being sold where you live?

 

[albireo]

Just a quick update to say I'm closer to a satisfactory resolution of this. I will make a longer post once I've tried a couple more things, I just wanted to say huge thanks to the people who have chimed in - turns out @koraks was on point with one of his comments and seems like I had a good intuition too, because I've had to tweak TWO things (each alone first, then together) to get where I am now.

Exciting!

 

[koraks]

Ah, very interesting; looking forward to the writeup & analysis! And, most importantly- I hope you're on the way to complete success now!

 

[albireo]

I just realised I never got round to updating this thread with my experiences following our discussion. I should really be taking pictures of the negatives to show my progress but I really haven't had the time so that will have to wait for another post.

In short, my results with the Adox C41 kit have much improved, and I now believe 2 factors were the main contributors to the poor results I was getting.

1. My negatives were overdeveloped, and this was due to the fact that, following the Adox instruction leaflet, I was doing a water bath between development and blix, which wasn't completely deactivating development. I thank @koraks who suggested to do away with this. I did, and used an acetic acid-based stop bath after development. This fixed my issues with overdevelopment. The base colour of my Kodak Gold 200 negatives now matches the one of the negatives I was getting by my 'trustworthy' lab. I note that I get similar improvements by pouring the blix soon after the dev, which I did for two test rolls.
2. My temperature control WITHIN THE TANK DURING DEVELOPMENT was not perfect. In spite of using a correctly functioning sous vide device and in spite of measuring temperature in the dev and blix bottles submerged in the bath before development, I had not sampled the temperature in the tank submerged in the bath during development. This is what I had hypothesised in post #11 and I decided to test it. I did a couple of dry (well, wet) runs with an expired test roll and sampled temperature during a 'development' step within the tank. Well - in spite of the sous vide measuring 38.1 on the display, in spite of my thermometer measuring 38.0 in the water bath and in spite of the same thermometer measuring 38.0 in the dev and blix bottles, temperature in the tank had fallen to 37 degrees and only crept back up to 37.4 in the 3.15 minutes of development. I found out that based on the temperature in the room I'm working in, and based on the shape of the bottles I'm using to store my dev and blix, I have to set the sous vide thermostat to a whopping 39.1 degrees to achieve a constant 38+-.5 degrees in the tank during development.

So I did a series of tests having changed 1) only. The results were better, no blocked highlights and no crazy global dominants in my scans, but still not perfect. I saw odd highlight- and shadow- specific dominants looking greenish or cyan-ish in the highlights and purplish or magenta in the shadows. That's when I decided to test what I reported in 2).

With 1) and 2) in place, my negatives are now what I would call 'professional grade', meaning I find them of satisfactory quality and I would consider switching completely to the Adox kit for all my C41. Please note I have no test strips so I cannot test these qualitative observations quantitatively.

Unfortunately, by the time I developed my 10th medium format roll using the method outlined in my first post PLUS the two fixes in this post, the quality of my negatives started decaying rapidly again. I can only ascribe this decay in performance to reuse of the chemicals. This is well below the 16 rolls per kit suggested in the Adox leaflet - I wonder if the fact that I'm not using the water bath between dev and blix anymore is shortening the life of the kit.

In any case, I've dumped all the chemicals, stored my notes, and have gone back to black and white development. I have - for now - concluded that these home C41 kits can in theory and with a lot of care offer professional quality results, however the 'window of opportunity' is too tight and I'm better off finding again a trustworthy lab given the level of results I am looking for.

For those of you tinkering with home C41 kits and scratching their heads, I have three lessons learnt to share

1. Don't blindly rely on the fact that you're using a sous vide. The fact that you're using a sous vide, that it generally works, and that your temperature seems constant everywhere before you start might mean less than you think and be not sufficient if your goal is to get machine-level controlled results. I shudder to think at what kind of results people doing 'hot water baths' without a sous vide are getting honestly
2. Tight temperature control is incredibly important in C41 development. Trust the Kodak tech sheets. Your work WILL be impacted by the effects of temperature inaccuracies, wether you can see it or not.
3. Don't blindly rely on what the C41 instructions in your kit are telling you. These kits might or might not try to strike a balance. Expectations around C41 development are, possibly, not those they were in the pro market of 30-40 years ago, with some newer film users being pleased by whimsical colour dominants and lomo-ish effects in their negatives, and other users going by the maxim 'you're scanning anyway, so you can fix anything in post', which might or might not be true for you (it is definitely not true for me). What I'm trying to say is that there might be a degree of 'acceptable slackness/artistry' in demanded results, reflected in a degree of acceptable slackness in the offered product. Do your testing, and decide for yourself what's good for you and what you expect for the money you spent.

 

[radialMelt]

Thanks for reporting back!

 

[koraks]

Thanks for reporting back!

Definitely! Thanks @albireo for sharing your observations, and glad to hear the problem seems to have resolved itself.

I wonder if the fact that I'm not using the water bath between dev and blix anymore is shortening the life of the kit.

I don't expect so; in fact, the opposite would be more likely. What kind of anomalies did you see on that 10th roll?

 

[radialMelt]

I am curious about the fact that point 1 (ineffective stop) would lead to over-development, but point 2 (low temps) would lead to under-development. I wonder what sort of complicated relationship happens there.

 

[albireo]

Definitely! Thanks @albireo for sharing your observations, and glad to hear the problem seems to have resolved itself.



I don't expect so; in fact, the opposite would be more likely. What kind of anomalies did you see on that 10th roll?

Well I only used the acetic stop for 2 rolls and for the following ones I skipped the stop bath altogether and poured the blix in directly. I'd expect there would be more than a few traces of developer still in the tank. I wonder if residual developer can contaminate the blix and lead to anomalies?

But you're right, there might be other reasons for the results becoming bad again. Another thing I can think of is that my dev+blix+stab were prepared a while ago, about a month now. How long does it take for the prepared, used developer to start going bad in general?

 

[koraks]

Seeing a reused developer going bad over the course of a month, especially without replenishment, is indeed quite plausible. It depends quite a bit in storage conditions and vessels.

If you value consistency as well as economy, you might consider using minilab chemistry and using it one shot. It's both qualitatively very hard to beat, and the cost per roll also turn out to be very attractive. The only drawback is that the initial/periodic expense is higher whenever you have to buy some new chemistry. Once that is out of the way, it's generally smooth sailing.