In response to those who wish to be apprised of my C-41 methodology

[trendland]

Please see revised post #62, above, as I had made an error with defining the WORKING SOLUTION. It is now stated correctly. - David Lyga

Good job David, very good job - I would like to wish you some others would end to "blame" your
"special" approach.

BTW : C41 is defined from Kodak what makes sense because of different labs worldwide as a standart.
Today 89% of that labs are closed. In some regions you habe trouble to find a lab.
C41 (with higher temps.)was created to give commercial labs the most economical profit.

Because from high temperature the developing machines can process more meter film per minute!

Rollei for example created years ago to first time a c41 process outside original specification.
With lower temperature and corrected times. This workflow is used meanwhile from lot of photographers at home (without shiftings) .....maybe little shiftings remmaining from time to time wich are is problem.
Remember : Within a days shooting outdoor there is different "color temperature in Kelvin" what also makes no problem (in most cases)!
The guys of Rollei/Maco recomanded alternate c41 with 20 and with 25degree Celsius.
(I would be sceptical of corrections at 20degree but with 25degree the process works good from own experience.)
At last the guys of Rollei are NOT the latest amatheuric lousers - they have experience with chems
since some decades.

So alternate c41 WITHOUT SHIFTS is ALLWAYS possible. (,but not so easy of course)
because you first have to find out the correct parameters what is an extensive research!

COMPLIMENTS DAVID!

 

[trendland]

Here we have a case of David Lyga stating, that he printed these negatives optically and had no problems with color cross over, and experts stating that "cross over will be so bad that it'll take a long time on the computer to fix it". If it takes you "a lot of time at the computer" to fix color cross over, then you're doing it wrong. To be honest, I'd rather trust David here.

Sorry Rudeofus I missunderstood your post! Perhaps I should give me more time and would allways read the last sentence of a post.!
So you "trust" David Lyga!

Then I can agree with you at last!

with regards

PS : I haven't had the time to try out but I will do next - but it looks like to be real correct (Davids approach)!

 

[David Lyga]

By first diluting the B and C, you make the final mixture for the developer stock MUCH EASIER to mix, because with that dilution (i.e., 1mL B + 8 water = 9mL DIL B. 1mL C + 7mL water = 8mL DIL C) you are NOW able to mix the SAME AMOUNT of A, B and C for your developer stock, in proper ratio.

Folks, I fail to see the reason for crossover: you are using the chemicals in their required ratio, but are diluting the final working solution precisely 10X what Kodak recommends. On the other hand, with my methodology, you are ALWAYS, WITHOUT EXCEPTION, using fresh, unused chemistry. It works, and if it does not, try either 7 min dev time or 9 or 10 min dev time for best contrast. Be forewarned that color paper is quite contrasty, thus the color negative is going to have to look 'low contrast'. This is especially relevant for sunlit, high contrast scenes. - David Lyga

 

[David Lyga]

Good job David, very good job - I would like to wish you some others would end to "blame" your
"special" approach.
!

I certainly appreciate your kindness and disdain for those who 'blame' me, but I assure you that there are some advantages gained from being persecuted by peers and family for much of my life. I am used to such angst emanating from my outspokenness and am happy to present tangible experiences that I have found to work for those with open minds, not minds mired in intellectual protocol and straitjacket formulae. (Actually, I am only a 'member' now because of that very outspokenness I dared to impart on "Soapbox".)

Remember folks, when chemical manufacturers present 'must dos', they present such for people who are not used to following rigorous paradigms, but, instead, are somewhat 'sloppy' in their work. Example: This is why stop bath mixtures are so overstated in intensity, when a stop bath one quarter as strong will do the job just as well. However, when I say 'one shot or you will be shot' I really mean it: there is NO capacity (both literal and figurative) for deviating or trying to obtain more capacity from my directives. You must not try 'to get more' from what I state, but my methods do, indeed, work.

Some simple test you can make to corroborate my intense dilutions that is easy to perform: Try this. With Dektol used for your B&W print developer, try deviating from the 1 + 2 'necessary' dilution. Instead, make that dilution 1 + 5. Process normally, but instead of 60 seconds use a minimum of 90 seconds. Your print will be just as good, with blacks just as intense. But, again, don't overuse that considerably dilute Dektol or you will run into trouble. In fact, hewing to my disciplines, I dilute Dektol 1 + 9 (one shot only) and end up with prints which are indistinguishable from any out there.

All of this distills into common sense. Color negatives have to be of lower contrast than B&W negatives are because when they print, they are printed onto higher contrast color paper. You want to retain that shadow detail within a contrasty scene and it is the colors, themselves, not tonal differences, which provide the contrast impact needed for a successful color image. But, again, that negative WILL have the requisite color panoply when using my methods of intense dilution.

Finally, I am the first to state that my detractors mean well and, in most cases, are intellectually superior to the feeble brain of David Lyga. However, there is something in life worth obtaining other than strict adherence to the written word. Even if my methods were inferior (they are not if adhered to) would such deviations for the sole purpose of artistic exploration be so treacherous to implement? Let's loosen up when we can and tighten up when we must follow certain procedures. We will all live longer. I continue to have much respect for those who defy me, who state that there are problems with what I say, who simply don't like 'the big mouth' (at least they are correct on that score!), but I still adhere to what I find through my 'frugal experimentation' and have no time for apology when doing that. There is more than the extant mind of David Lyga out there and for that fact we should, collectively, be intensely grateful. - David Lyga

 

[RPC]

David, as I have said in the past, your process is not the problem per se. If someone tries it and it works for them that's fine. The problem is that you never warn people that this is not the proper process and as such may not give expected results. Lack of such warnings can imply to many that it gives proper results which tests have shown it does not, despite what you see. Since you don't warn them, others who have knowledge of the critical nature of the C-41 process feel the need to do so in the interest of the photographic community.

 

[Wayne]

Right : PET is working good! Rollei use it - and stated from what advantage PET for developer is
(NOT TO ALL KIND OF CHEMS BE AWARE)
But the "key" with PET from the supermarket is : You shouldn't use the thin-walled PET bottlest !

with regards

Soda pop/soft drink bottles and the water bottles I currently use are fairly thin and flexible, but not the thinnest, and they work great. I have year-old RA4 developer that is good as new. But this is really off topic for this thread. Everyone has their preferences and few are going to change.

 

[Rudeofus]

David, as I have said in the past, your process is not the problem per se. If someone tries it and it works for them that's fine. The problem is that you never warn people that this is not the proper process and as such may not give expected results. Lack of such warnings can imply to many that it gives proper results which tests have shown it does not, despite what you see. Since you don't warn them, others who have knowledge of the critical nature of the C-41 process feel the need to do so in the interest of the photographic community.

Here is David's explicit statement, that his process does not conform to the standard process for C-41 negative film. It appears in the first port of this thread, for all to see:

That is it! I have CONSISTENT results, costs are minuscule, and, although Kodak would probably relegate the soul of Spanish Inquisitor Tomas de Torquemada to deal with my heresy, I have the prints, beautiful prints, to prove that my deviance and treachery never cost this planet a soul, (or, monetarily, never a sou)

If you want to see something more explicit than what he wrote: your post with a more mundane warning will remain firmly attached to this thread, for all to see. I am convinced that David will suffer horribly and weep uncontrollably for months, because some folks here wouldn't touch his process with a ten foot pole or find some other way to express their rejection of it.

BTW: some people did do sensitometric tests with David's process and found some deviations, as documented here in this thread. They also found comparable deviations with all other available C-41 formulas, so don't ring the bells of victory yet.

 

[RPC]

Here is David's explicit statement, that his process does not conform to the standard process for C-41 negative film. It appears in the first port of this thread, for all to see:


If you want to see something more explicit than what he wrote: your post with a more mundane warning will remain firmly attached to this thread, for all to see. I am convinced that David will suffer horribly and weep uncontrollably for months, because some folks here wouldn't touch his process with a ten foot pole or find some other way to express their rejection of it.

BTW: some people did do sensitometric tests with David's process and found some deviations, as documented here in this thread. They also found comparable deviations with all other available C-41 formulas, so don't ring the bells of victory yet.

That is not a "warning" in the sense one would expect to see. I have used Kodak standard chemistry and have gotten very consistent sensitometric results. I have not tried David's method but have tried various other non-standard methods including Patrick Dignan's divided, room temperature developer and got nothing but low contrast and crossover and wide variations among different films. So this is enough to convince me, along with PE's knowledge of the critical nature of the C-41 process that more descriptive warnings are in order in lieu of actual test results. David is the one promoting this so I would expect him to do the warning so others don't have to.

 

[MattKing]

Good luck using digital tools to deal with substantial colour crossover.
And prepare to spend a lot of time at the computer.

Here we have a case of David Lyga stating, that he printed these negatives optically and had no problems with color cross over, and experts stating that "cross over will be so bad that it'll take a long time on the computer to fix it". If it takes you "a lot of time at the computer" to fix color cross over, then you're doing it wrong. To be honest, I'd rather trust David here.

I probably should have put more emphasis on the word "substantial".
To be clear, I was not intending to say that David's approach would inevitably lead to useless results.
Instead, I was responding to the fairly prevalent notion that if the negatives are "off" you can always fix them digitally.
My response to that is basically - "it depends".
If the deviation from "correct" is in the nature of a colour cast, correcting the problem is very simple, whether one prints optically or uses digital tools.
However, if the deviation from "correct" is in the nature of a colour crossover, correcting the problem can vary from being relatively simple to being incredibly difficult if not practically impossible, and the difficulty may be functionally different, depending on the subject and the amount that the importance of colour fidelity may vary across the different parts of the subject.
If one ends up with a negative that when printed straight optically yields, for example, highlights with a strong magenta cast, mid-tones that vary between slightly magenta, neutral and slightly green, and shadows that show a strong green cast, then it will not be easy or simple or quick to correct the problems digitally.
I've told this story before, but when I used to work as a colour printer making (optical) proofs and small enlargements for professional photographers, we had one customer who did develop his own film (to save costs). His results had so much crossover we ended up refusing further work from him, unless the films were developed by others.
When the bride's white wedding dress prints as sickly magenta and the groom's black tux prints with an ugly green cast, the results are painful!

 

[1kgcoffee]

Thanks for posting this. Just a few questions. I plan on purchasing some kodak chemicals to last for a few years.

Is it the LORR or standard, or does it matter?
How long do the developer chemicals last? Could these last 10+ years with decent results? It is my understanding that bleach lasts practically forever but the developer chemicals go bad. I am wondering if it is not better to purchase cd-4 and mix homebrew?

What is your methodology for ra-4?

I have a feeling this method will yield better results that are cost effective compared to standard kits.

 

[Mr Bill]

As any of us has dabbled in C-41 processing knows, capacity is all over the brand ball park. Many say 8 per qt/liter. Then there is the matter of increased time to extend capacity

There really is not much leeway here with respect to the process specs; the so-called capacity is really more of: "how far off is it allowed to get before it bothers you?" So Kodak, as the designer of the process, takes a fairly conservative approach; some of the aftermarket suppliers rely on the frugal nature of their customers, who seem to not be bothered, or even notice, the difference.

"Perfection is the enemy of good enough."

Yes, I think the main thing here is, what does "good enough" mean?

David hasn't said what sort of thing he photographs nor how finicky he is, so it would be hard to judge. A lot of things, especially scenic shots, have a lot of leeway for "interpretation;" how can one look at a landscape and say, "oh the change in color of foliage looks like a color cross?" But if you shoot certain sorts of things, say products, or one of my specialties, studio portraits, this can be real touchy. Depending on how finicky you are. If you were perfectly satisfied with the quality of mini-labs in their heyday, circa 1990s, then you're unlikely to notice color crosses; good quality portrait work is whole 'nuther animal. (The place I worked also owned a large 1-hour lab chain; they set up a number of attached portrait studios as a trial, but could never get what I'd call high quality. Note that I had some involvement in this.)

The rest of this post details some of my experience with the portrait chain, going into how we tested for film/paper compatibility. No need to read further unless you have specific interest. It's mainly to demonstrate how some users can be more finicky.


I've spent a lot of years working with high volume processing for a large portrait chain. On the general topic of color crosses, this was a major issue for us for many years. As Kodak pro color neg films, the only thing we ever used, went through different generations - VPSII, then VPSIII, and the first Portra 160 - we would thoroughly test each one, printing one the appropriate professional paper. Since portraits were our business, this was a major part of our testing. We'd shoot a wide range of exposures (with a large number of studios, you always have someone screwing up the exposure) using models with a variety of complexions and hair color. Then they were all hand color-balanced (optical printing) to match the skin tones to within about 1cc color. (This testing regimen went on until about a dozen years ago, by which time we were fully digital.) One main requirement was that color crosses across the skin tones - shadow to highlights - had to be minimal. A common problem in the earlier years, depending also on the paper used, was that the brightest skin highlights would go "cool," meaning a bluish or cyan tone. In later years, even across paper brands (still using the pro portrait papers, though) these color crosses were minimal - on the order of 1 cc or less. Which we judged that no normal customer would see.

Now, when we did these tests, all of our processors were pretty well nailed down with respect to control strip plots. So I truly do not know how the test result would be with an out-of-spec film process. But I do have a sense of what the control plots will do if when the temperature control goes off, or a replenisher pump fails. The "speed" between the color layers (c, m, and y) will shift, as well as the relative contrast levels. So I am pretty certain that the grey scales would not remain dead neutral. The skin tones are not "predicted" by control strips, as skin doesn't have a neutral balance on the exposure, like the control strips do. So the best way I knew to test the skin tones for color crosses was to shoot and print it. If someone has not done this I don't know how they could possibly anticipate what it would be like. (Today, with scanning the standard method, it's a different sort of game; I can't say too much about it.)

Anyway, given the difficulty we had, with the best materials and tight process controls, I cannot imagine that someone can pick some arbitrary dilution/time/temperature and match the results. My best guess is that David has more, uh, relaxed standards, or shoots subjects that don't really demand a specific sort of color reproduction - one where color "errors" don't really stand out.

 

[trendland]

Thanks for posting this. Just a few questions. I plan on purchasing some kodak chemicals to last for a few years.

Is it the LORR or standard, or does it matter?
How long do the developer chemicals last? Could these last 10+ years with decent results? It is my understanding that bleach lasts practically forever but the developer chemicals go bad. I am wondering if it is not better to purchase cd-4 and mix homebrew?

What is your methodology for ra-4?

I have a feeling this method will yield better results that are cost effective compared to standard kits.

I would state it is per note market onto the package of Tetenal liquits : 2 years !.....?
But in the past local dealers stored it for a while before chems have been sold !
They usualy can last longer in unopened canisters. The 2 years oft Tetenal chems are in concern
of manufacturers warranty!
How long can they last max.? You may double the warranty for sure!
If you buy chems at a local dealer it happened in the past that the dealer didn't sell fresh chems to you because he himself odered the stuff 1 year before.
But manufacturers want to get safe from warranty ! They would avoid a case - a dealer is storing the stuff over 2 full years before he can sell it - and you will not use it at once - but you open the last canister after 4 full years to the first time!
Therefore you will not get a full 4years warranty (because your stuff would be in this example 6years after production)
I guess most chems are good enough for 6 - 8 years - but 10 - 12 years??? I don't expect that long time!

Solution : Raw chems from powder = > 20 years!

with regards

 

[trendland]

Thanks for posting this. Just a few questions. I plan on purchasing some kodak chemicals to last for a few years.

Is it the LORR or standard, or does it matter?
How long do the developer chemicals last? Could these last 10+ years with decent results? It is my understanding that bleach lasts practically forever but the developer chemicals go bad. I am wondering if it is not better to purchase cd-4 and mix homebrew?
Ähhm just read your post again CD4........it isn't avaible from others than liquit AFAIK!
Because it is a complexity chemical structure for its own (no raw chem)!
Does anyone can say how long CD4 can be stored max. without a noticable lost of its characteristics?

with regards

 

[trendland]

That is not a "warning" in the sense one would expect to see. I have used Kodak standard chemistry and have gotten very consistent sensitometric results. I have not tried David's method but have tried various other non-standard methods including Patrick Dignan's divided, room temperature developer and got nothing but low contrast and crossover and wide variations among different films. So this is enough to convince me, along with PE's knowledge of the critical nature of the C-41 process that more descriptive warnings are in order in lieu of actual test results. David is the one promoting this so I would expect him to do the warning so others don't have to.

RPC - I guess one may say : "everything you do after you enter a darkroom divorced at your own risc"
If you have this in mind you have a good "starting point"

with regards

 

[Rudeofus]

However, if the deviation from "correct" is in the nature of a colour crossover, correcting the problem can vary from being relatively simple to being incredibly difficult if not practically impossible, and the difficulty may be functionally different, depending on the subject and the amount that the importance of colour fidelity may vary across the different parts of the subject.

I agree that negs with color crossover can be difficult/impossible to print optically, but once you go the hybrid route, corrections are really trivial and nothing to be afraid of. I have done RGB curve corrections with GIMP on linux 20+ years ago. Yes, you read that number 20 correctly.

That is not a "warning" in the sense one would expect to see.

I understand the need for an explicit warning in all these instances, in which physical harm can result from sloppily or blindly following a procedure. David's warning is entirely appropriate for the risk people face when following his modified process. If people don't understand what he means, then losing a roll of film should be their least concern.

 

[trendland]

There really is not much leeway here with respect to the process specs; the so-called capacity is really more of: "how far off is it allowed to get before it bothers you?" So Kodak, as the designer of the process, takes a fairly conservative approach; some of the aftermarket suppliers rely on the frugal nature of their customers, who seem to not be bothered, or even notice, the difference.

Yes, I think the main thing here is, what does "good enough" mean?

David hasn't said what sort of thing he photographs nor how finicky he is, so it would be hard to judge. A lot of things, especially scenic shots, have a lot of leeway for "interpretation;" how can one look at a landscape and say, "oh the change in color of foliage looks like a color cross?" But if you shoot certain sorts of things, say products, or one of my specialties, studio portraits, this can be real touchy. Depending on how finicky you are. If you were perfectly satisfied with the quality of mini-labs in their heyday, circa 1990s, then you're unlikely to notice color crosses; good quality portrait work is whole 'nuther animal. (The place I worked also owned a large 1-hour lab chain; they set up a number of attached portrait studios as a trial, but could never get what I'd call high quality. Note that I had some involvement in this.)

The rest of this post details some of my experience with the portrait chain, going into how we tested for film/paper compatibility. No need to read further unless you have specific interest. It's mainly to demonstrate how some users can be more finicky.


I've spent a lot of years working with high volume processing for a large portrait chain. On the general topic of color crosses, this was a major issue for us for many years. As Kodak pro color neg films, the only thing we ever used, went through different generations - VPSII, then VPSIII, and the first Portra 160 - we would thoroughly test each one, printing one the appropriate professional paper. Since portraits were our business, this was a major part of our testing. We'd shoot a wide range of exposures (with a large number of studios, you always have someone screwing up the exposure) using models with a variety of complexions and hair color. Then they were all hand color-balanced (optical printing) to match the skin tones to within about 1cc color. (This testing regimen went on until about a dozen years ago, by which time we were fully digital.) One main requirement was that color crosses across the skin tones - shadow to highlights - had to be minimal. A common problem in the earlier years, depending also on the paper used, was that the brightest skin highlights would go "cool," meaning a bluish or cyan tone. In later years, even across paper brands (still using the pro portrait papers, though) these color crosses were minimal - on the order of 1 cc or less. Which we judged that no normal customer would see.

Now, when we did these tests, all of our processors were pretty well nailed down with respect to control strip plots. So I truly do not know how the test result would be with an out-of-spec film process. But I do have a sense of what the control plots will do if when the temperature control goes off, or a replenisher pump fails. The "speed" between the color layers (c, m, and y) will shift, as well as the relative contrast levels. So I am pretty certain that the grey scales would not remain dead neutral. The skin tones are not "predicted" by control strips, as skin doesn't have a neutral balance on the exposure, like the control strips do. So the best way I knew to test the skin tones for color crosses was to shoot and print it. If someone has not done this I don't know how they could possibly anticipate what it would be like. (Today, with scanning the standard method, it's a different sort of game; I can't say too much about it.)

Anyway, given the difficulty we had, with the best materials and tight process controls, I cannot imagine that someone can pick some arbitrary dilution/time/temperature and match the results. My best guess is that David has more, uh, relaxed standards, or shoots subjects that don't really demand a specific sort of color reproduction - one where color "errors" don't really stand out.

Mr. Bill : if I ever found a lab in the past (1980 -1998) with just a "near by" workflow you described
from your own experience (RESPECT!) - then I would liked to have paid the prices my labs have
allways demanted!

with regards

 

[trendland]

I agree that negs with color crossover can be difficult/impossible to print optically, but once you go the hybrid route, corrections are really trivial and nothing to be afraid of. I have done RGB curve corrections with GIMP on linux 20+ years ago. Yes, you read that number 20 correctly.


I understand the need for an explicit warning in all these instances, in which physical harm can result from sloppily or blindly following a procedure. David's warning is entirely appropriate for the risk people face when following his modified process. If people don't understand what he means, then losing a roll of film should be their least concern.

If one would recomand to brew C4 instead of CD4 (with full operational recipe) such kind of warning
you mentioned wouldn't be enough...if you think of the local neigborhood of such darkroom...!

with regards

 

[David Lyga]

My best guess is that David has more, uh, relaxed standards, or shoots subjects that don't really demand a specific sort of color reproduction - one where color "errors" don't really stand out.

Actually, my naked eye is quite critical and, unlike most who judge the flesh tone for accuracy, I judge medium gray, as I feel that that neutral color is the first to yield crossover results. I have to say that I am satisfied with my results and see none, or tiny, crossover. Let's be honest: With (recommended) reuse of chemistry is there not a built in deviance with color developer accuracy because the developer is partially used before new film begins its development? I do not reuse chemistry; each roll developed has new, albeit diluted, developer.

People who disagree are not only permitted to do so, but encouraged (by me) to do so This is what yields positive results, overall, in life, as it is democracy in action with synergy at work. But please do not think that I am 'putting up' with faulty pictures. My pictures are years better than what the labs used to deliver. I cannot be more forthright than that. - David Lyga

 

[Mr Bill]

Actually my naked eye is quite critical and, unlike most who judge the flesh tone for accuracy, I judge medium gray as I feel that that color is the first to yield crossover results.

No, the grey scales have been (able to be) pretty reliably neutral for many years, say by 1980 or so. Again, this is with the Kodak professional color negative film of the day (I'm thinking it was probably VPSII?) optically printed onto the matching pro papers, either from Kodak, Konica, or Fuji (all were very good). The big issue in portraiture after that was largely in keeping good skin tones across the full tonal range, and for this to happen with a wide range of skin tones, from very pale to very dark complexions.

I've worked with dozens of professional color correctors over the years, and (sorry) I'm also skeptical about someone's independent "color skills" without some sort of "qualification," a test of sorts. What we did was to use the "Farnsworth-Munsel 100-hue test" for everyone who wanted to color correct. (The test has a series of pastel-like color "chips" covering the range of hues that people can see. The goal is to arrange them in order.) If someone has a weakness in ability to discriminate colors, it's a very sensitive test; few people get a perfect score. Normally you give the test twice, as most people improve slightly on the second time (I guess they are "learning" how to take the test, although it seems like it shouldn't happen.) We had probably 150 tests on file during the time I was a QC manager; there were, as I recall, 3 or 4 people with double perfect scores. The ones I knew just went right through the test, no delay or hesitation, and knew they had it perfect (the test typically takes 20 minutes or so, but these people with the "super discrimination can do it in 4 or 5 minutes). A handful of people had very weak scores (due to color blindness) and they knew it. The rest really had almost NO IDEA what their score would be (actually they had ideas, but were often completely wrong about how they scored). So my experience is that most people really don't know, and are often mistaken, about their color discrimination ability; consequently I'm always skeptical unless their ability has somehow already been qualified.

Anyway, I am extremely skeptical that someone can vary the C-41 process by the amount that you have, and still print optically with no obvious color crosses. So you can have an idea where I'm coming from. Now, if you had worked in a pro lab, and the other color correctors had acknowledged you as one of the best, this would make me rethink my position, but otherwise... well it goes against all of my experience.

As a note, you can't judge this accurately without a proper light source. Modern fluorescent lamps, the energy-efficient ones (often have a green stripe on the end) are especially bad for this. When in doubt, use window light for a reality check; it might bias your color preference, but you should be able to see subtle color differences through a neutral (or color) ramp.

 

[RPC]

Actually, my naked eye is quite critical and, unlike most who judge the flesh tone for accuracy, I judge medium gray, as I feel that that neutral color is the first to yield crossover results.

A single gray is not useful for determining the presence and nature of any crossover. A gray scale is what is commonly used, both for visual determination and for plotting characteristic curves. Control strips use two gray patches in the case of the HD-LD densitometer method. But a single patch tells you nothing. There must be density variations, and yes, should be perfectly neutral colors.

 

[Mr Bill]

Mr. Bill : if I ever found a lab in the past (1980 -1998) with just a "near by" workflow you described
from your own experience (RESPECT!) - then I would liked to have paid the prices my labs have
allways demanted!

with regards

Thanks, but these tests were strictly to select the film/paper combinations that were acceptable to us, for typically a 2-year contract with the manufacturer. We ran a pretty large volume of work - well over a million 8x10" print units per week, so the consequences of a bad decision were pretty significant.

In actual production work, we ran with an "official limit" of +/- 5cc color; anything beyond that was supposed to be reprinted. But in reality we ran a lot closer to 2cc most of the year (in our busiest time of year this slipped a lot, and I'm sure we shipped a lot of crap, but...).

All of the work we did was our own; it was a mass-market portrait chain where all of the photographers were employees. Essentially the outfit was like a picture factory. The studios supplied the "raw materials," aka exposed film, which was then "processed" by the "factory," aka the photofinishing lab. So anyway, we didn't do outside work, except occasionally as favors.

 

[Mr Bill]

A single gray is not useful for determining the presence and nature of any crossover. A gray scale is what is commonly used, both for visual determination and for plotting characteristic curves. Control strips use two gray patches in the case of the HD-LD densitometer method. But a single patch tells you nothing. There must be density variations, and yes, should be perfectly neutral colors.

This is a good point, and now I'm wondering if there has been a misunderstanding of what a color cross is.

The normal understanding is that it is the situation where a lighter vs darker shade of a color has a different cast, and thus cannot be color-corrected (without special means, such as a colored mask). For example, a gray "ramp," going from light to dark, might be yellowish at one end, and bluish at the other. If you try to correct the yellow end, then the blue end problem gets worse. And vice versa.

But there can be color cross problems in colors other than gray. I used the example of flesh tones. If the overall flesh tone is good, but the flesh highlights are "cold," meaning bluish, then this is a color cross, and is not (normally) correctable. If you try to correct the bluish highlights by making it yellowish, then the previously ok flesh tones now become too yellow.

As RPC says, the control strips use "gray" patches, so could help to show a color cross there. But it's possible to have a good neutral gray ramp at the same time that certain colors, such as flesh tones, have color crosses. So this is where we rely on having a "well-behaved" film response, and once you deviate from the manufacturer's instructions, you are on your own.

 

[trendland]

Thanks, but these tests were strictly to select the film/paper combinations that were acceptable to us, for typically a 2-year contract with the manufacturer. We ran a pretty large volume of work - well over a million 8x10" print units per week, so the consequences of a bad decision were pretty significant.

In actual production work, we ran with an "official limit" of +/- 5cc color; anything beyond that was supposed to be reprinted. But in reality we ran a lot closer to 2cc most of the year (in our busiest time of year this slipped a lot, and I'm sure we shipped a lot of crap, but...).

All of the work we did was our own; it was a mass-market portrait chain where all of the photographers were employees. Essentially the outfit was like a picture factory. The studios supplied the "raw materials," aka exposed film, which was then "processed" by the "factory," aka the photofinishing lab. So anyway, we didn't do outside work, except occasionally as favors.

Understand - the commercial labs comming up in the beginning 70th I remember were kicking bw away with dumping pricing to color works. Within 9month color was cheaper in comparison to bw.
Quality was poor......years later professional labs lost origin workflow.
At last there was no difference between...., beside high pricing of labs for professionels.

with regards

 

[Paul Verizzo]

David, upthread I commented on the fact that in your original thoughts on using dilute C-41, you were using 1:15, now 1:9. You didn't respond to that.

You note here that one must have enough developer. Of course! Is this why you changed your operating ratio?

It occurred to me that if one is operating on the edge of having enough developer, the difference between tanks could matter. Larger plastic tank volumes vs. SS tanks.

Thanks!

 

[David Lyga]

David, upthread I commented on the fact that in your original thoughts on using dilute C-41, you were using 1:15, now 1:9. You didn't respond to that.

You note here that one must have enough developer. Of course! Is this why you changed your operating ratio?

It occurred to me that if one is operating on the edge of having enough developer, the difference between tanks could matter. Larger plastic tank volumes vs. SS tanks.

Thanks!

Best to contact me directly, as I post so much I don't have time to answer all unless contacted directly.

Yes, even 1 + 14 will work, but it is easier to use 1 + 9. Of course, time must increase for the extra (1 + 14) dilution, but, given the idiocy of perpetually trying to get yet more blood out of a stone, I think that we can establish 1 + 9 as a handy synergism of cost and ease and predictability. - David Lyga