Color Corrective Masking with Digital Negatives

[donbga]

Ok, you're right guys. I best buck up and put on my learning hat.

Two links you find useful:

Real World Color Management - AbeBooks


Real World Color Management: Downloads

 

[donbga]

Two links you find useful:

Real World Color Management - AbeBooks


Real World Color Management: Downloads

Oh yeah, you might find this useful:

Dead Link Removed

 

[gmikol]

I've heard "Real World Color Management" recommended numerous times in various different places, and Luminous Landscape is usually a pretty good resource, though I know nothing about the publication that Don references.

I just want to point out that everything I know about color management, I've learned from the internet (so it's probably all wrong ). You might have to dig a little bit, but there are free resources out there, if you're good at integrating information from multiple sources. Google is your friend.

--Greg

 

[mprosenberg]

Holmburgers,

There is no value in using a mask on a digital negative. You would correct everything in PS to obtain the contrast locally that any masking could give you; in addition you would be doing it in a way that you would see the final outcome. Unless you are using PS to output the negative, and not QTR, your mask would be neutral in color, unless you print the negative for B/W as a false color digital negative to expose B/W paper. You would not use an ICC profile, but rather profile each color to see how it blocks light on B/W paper.

Color masking is useful for printing enlarged 4x5 negatives to alter local contrast. I have been doing that for years, as well as making dodging and burning masks.

Mike

 

[holmburgers]

Hi Mike,

I might be mistaken, but I think you're not talking about color-corrective masking. This technique is not at all for the purpose of altering contrast. It's a traditionally analog technique that I'm interested in applying digitally, therefore it has nothing to do with QTR, or anything related to the negative's density, etc.

Here is a (somewhat crash-course) description of color masking...

For example, an Ektachrome cyan dye absorbs 100% of red light, just as it should do, but it also absorbs 30% of green light. This means that the cyan dye also contains 30% magenta that does not belong there. If we shoot a principle mask through the red filter and develop it to 30% of the contrast or gamma that is needed for a separation, then put that on top of the raw film when the separation shot through the green filter is made (the one used to expose the magenta matrix), then everywhere cyan and magenta both appear in the image 30% of the exposure will be blocked. This way the 30% false magenta in the original cyan dye in the slide can be eliminated. This is all very difficult to follow even for people who deal with this all of the time, but it is important to get the idea. By shooting through principle masks when making the separations, the original distortions in the slide dyes can be eliminated. This purifies the colors and makes the colors in the final print closer to those in the original scene.

This is actually talking about color masking while making the separations (necessary with slide film only). Another set of color masks should be used in making the matrices to compensate for the printing dyes.

Alternatively, it's possible that I'm not fully understanding what you're saying. At any rate, hope to get this sorted out.

I'm also interested in what you mean by "color masking for printing enlarged 4x5 negs."

(lastly, I never intended to give the impression that we were going print out a separate mask to register with the negative. This would all be done as 1 singular masked negative.)

 

[davosproject]

With a digital workflow you are not stuck with a static, immutable original negative. If there is too much of this or that colour, you change the file with curves or whatever. You are printing with an ideal negative every time.

 

[holmburgers]

davo, I think what you mention is true, but not with full recognition of what color corrective masking does.

I'm sorry to keep beating a dead horse, but I just wanna make sure we're all on the same page (myself included!)

Changing the curve shape of a negative will affect the color saturation and the color balance, but only by affecting the overall balance of colors in the image and their distribution as determined by the individual negatives. It is still not accounting for deficiencies in the printing dyes.

As an example, let's say we have a color photograph in PS. I'm assuming there's a simple command that will split it into CMY(K) negatives. This would be akin to separating a color negative with wratten filters. Let's then assume that we have tweaked the curves of each sep-neg to produce a final print that looks just like we want it to. If we use these negatives to make a pigment print or a dye transfer print, they will still not reproduce the scene as life like as possible without the use of color corrective masking.

I have no doubt that ICC profiles can do what c.c-masking can do, since they actually have a provision for seeing the color in the final print and making adjustments from that.

 

[holmburgers]

Bob C., does (did) anyone use color corrective masking with ciba/ilfochrome? I know about unsharp masking, highlight/shadow, etc., but to c.c-mask with Ilfochrome would require making negative masks through separations, and then printing through the masks with sep-filters and 3 separate exposures. Based on this, I'm guessing no one did it.

RA-4 printing, or C-printing has always used this technique... but the beauty is that you don't have to do anything because color negatives use an integral mask. They actually create masks within the negative upon development, and this is possible because the visual look of the negative is immaterial to its performance with a corresponding paper. They are masked to compensate for deficiencies in the paper's dyes.

Furthermore, I suspect that printing digital pictures has, since its inception, utilized this same line of thinking. Whether that is from an ICC profile, or just in the manner in which it is processed within the computer, is unbeknownst to me, but I'm speculating.

My point is that c.c-masking is all around us, and we might not even realize it. It was standard practice with carbro & dye-transfer. Cibachrome is one example where I don't see how this problem is addressed.

AMENDMENT: See here. Apparently Cibachrome-II A used automatic color masking as well. How this was achieved, I can't say. Perhaps through careful sensitization(??).

 

[Bob Carnie]

Chris- yes we did use colour corrective masks to eliminate unwanted casts,, for example a mask to take the cyan blue out of bridal dresses , or a mask to cool down a sky and darken at the same time.

Drew W here would be a good source as he still works with complicated mask making and correction,I now only work with PS and a Lambda to make negs and yes I will be making accent negatives that will push colour a bit the same as I will make third or fourth negs to build up colour density.,, I did photocomposition for 5 years as a major lab in Toronto, and yes we did use colour corrective masks to solve problems.
I also did a lot of mask making for Ciba Chrome and on top of highlight protection masks for highlight control we would indeed make colour masks to accent certain colours or push them beyond where they would normally land when every thing else in the image was balanced.
We also worked extensively with Lee filters and a dye stepwedge neg to figure out how to change colours... Try getting variations of red on a RA4 print, very hard to get a lot of difference but by wacking out the red information you can eventually come up with many variations of red that would not look proper by observing the monitor. In fact it would look outrageous and not viable. We called this colour by number and it was big in the day and the only way to match pantone # on a product that was not calibrated to Pantone swatch books.
Do you understand where I am taking this......... each paper and ink you ever use will have a vocabulary distinctive to it..Profile..... by fudging(old lab term) the colours by use of wierd filters we could predictably and easily reproduce more pantone colours that may not be obvious for that paticular colour paper. The commanality was a dye stepwedge properly neutralized, today the more sophisticated machines have onboard step wedge calibration capabilities. Bob Pace was a photo comp specialist,,,,, that is exactly what I was, and to be one you needed to work with lith pos neg, spreads chockes, diffusion techniques, layering techniques, able to butt images together, overlap images, colour correct various sources of originals onto a single sheet of colour inter neg or E6 film. If you were using colour interneg the standard was 8x10 Kodak, if you were using E6 the standard was 16 x20 full sheet that would be set up for magazine work and the separator would separate our film only once as our job was to make sure the images or comps all worked together and were colour corrected as such on a single sheet of film.

lately
I also register inkjet paper and do multiple passes on the inkjet paper that one single file could not accomplish, those saying that everything can be on a single file and a single pass or printing are really not pushing the envelope far enough or maybe have not had enought prints behind them to realize there are hundreds of ways of accomplishing better prints.

Making dye transfer prints, which I never have done, required a good colour masking understanding , or the prints would look like crap, I am only observing your posts lately and you seem to be delving down this road quite a bit where colour correction techniques was very critical.

hope I am confusing you even more.

Bob

Bob C., does (did) anyone use color corrective masking with ciba/ilfochrome? I know about unsharp masking, highlight/shadow, etc., but to c.c-mask with Ilfochrome would require making negative masks through separations, and then printing through the masks with sep-filters and 3 separate exposures. Based on this, I'm guessing no one did it.

RA-4 printing, or C-printing has always used this technique... but the beauty is that you don't have to do anything because color negatives use an integral mask. They actually create masks within the negative upon development, and this is possible because the visual look of the negative is immaterial to its performance with a corresponding paper. They are masked to compensate for deficiencies in the paper's dyes.

Furthermore, I suspect that printing digital pictures has, since its inception, utilized this same line of thinking. Whether that is from an ICC profile, or just in the manner in which it is processed within the computer, is unbeknownst to me, but I'm speculating.

My point is that c.c-masking is all around us, and we might not even realize it. It was standard practice with carbro & dye-transfer. Cibachrome is one example where I don't see how this problem is addressed.

 

[holmburgers]

Thanks Bob... totally confused now.

Haha, no not really, just a lot of density in all of this. Yes, I'm very interested in these color techniques and fascinated by the complexity of it all. As you may well realize, I'm not an expert printer or even an intermediate printer. I'm a beginner. But I do hope to make quality color prints using these techniques in the future and in the meantime I'm trying to soak as much up as I can from people like yourself who are industry leaders and know the old way of doing things. I like to learn something new every day, and sometimes every other hour.

It just seems to me that having an awareness of the past will always make one more adept at whatever techniques arise in the future. You gotta know where you came from to know where you're going!

 

[Bob Carnie]

Photo Shop owes it existance to the old techniques, Its pretty powerful software program, wish I had it 30 years ago.... learn the old and the new.

 

[donbga]

Thanks Bob... totally confused now.

Haha, no not really, just a lot of density in all of this. Yes, I'm very interested in these color techniques and fascinated by the complexity of it all. As you may well realize, I'm not an expert printer or even an intermediate printer. I'm a beginner. But I do hope to make quality color prints using these techniques in the future and in the meantime I'm trying to soak as much up as I can from people like yourself who are industry leaders and know the old way of doing things. I like to learn something new every day, and sometimes every other hour.

It just seems to me that having an awareness of the past will always make one more adept at whatever techniques arise in the future. You gotta know where you came from to know where you're going!

Your post reminds me of an often quoted phrase used in business and engineering - "Paralysis by analysis."

Analysis paralysis - Wikipedia, the free encyclopedia


Start printing Chris, you need to learn from your failures.

 

[holmburgers]

Don, I totally agree that I need to start printing and learning, which I do as often as I'm able. But, I am online so often because I am in front of a computer between 10am & 4pm every weekday for my job. Between my duties at work, which I perform admirably and to the complete satisfaction of my employers and co-workers, I try to learn as much as I can from the fine people online and to push my academic understanding of the science of photography beyond what it might be without discussions of this sort!

Nothing would please me more than to spend everyday in the darkroom.

Paralysis by analysis has not hindered any of the darkroom work I do. It continues on at a pace dictated by the responsibilities of my life. This analysis allows me to learn new things, have new insights and ultimately have new ideas.

This is not meant as a bad joke, but would you consider Steven Hawking to be paralyzed by analysis? No, he represents the pure, distilled ability of the mind. I'm not comparing myself to him of course, but thinking can get you somewhere.

Don, I totally respect your opinion and your experience but your subtle derision and persistant dismissal of my theoretical inquiries is very apparent to me, and has been going on for some time now.

Perhaps you should stop worrying about me so much.

All that being said, I understand what you're getting at, believe me.

 

[pschwart]

I think that Don is suggesting that your conjecture and hypotheses about masking for color correction need to be tested hands-on. That seems spot-on to me and not derisive at all. Personally, I think you are going to find that a digital negative won't require these masks -- if the system has been properly profiled color correction won't be necessary. That doesn't mean you can't incorporate color masking into your personal workflow, but it's a lot of extra work and would seem counter-intuitive to a lot of printers.

 

[holmburgers]

Hi Philip,

To be honest, my admittedly heated response is due to a long history of such responses, with a few particular ones in mind. It's a private matter that I've aired publicly, out of frustration.

Don does a noble thing by saying, "hey young guy who's talking a lot and not showing many results, why don't you just get down to work and quit talking about it". (at least, that's what I take from it, and suspect what I'm intended to)

To his credit, he's not wrong by any means.

But my main point is, perhaps by starting this thread I never even intended to make digital negatives with masks, and actually that's the truth! I don't, as I'm working with analog negatives.

My intention was to start a discussion that might lead to a new way of thinking about digital negatives, and to my mind, this simple method gleemed from older analog color processes requires a lot less work, a lot less editing suite knowledge & might very well result in equally good color quality. A method that is much more intuitive in my mind.

I just feel that a comment like Don's effectively says, "let's stop talking about it".

That's all...

I appreciate your diplomatic comments.

 

[pschwart]

just to clarify: I thought we were talking about digital separations made in Photoshop. Where do analog negatives fit into this discussion? Sorry if I have missed something.

I never even intended to make digital negatives with masks, and actually that's the truth! I don't, as I'm working with analog negatives.

 

[holmburgers]

We are talking about digital separations, I'm just saying that personally I'm currently using analog negatives. However, that doesn't mean I don't want to learn or investigate the use of digital negatives.

This kind of masking though was traditionally done in an analog workflow though.

 

[davosproject]

There is nothing wrong with letting the mind wander undisciplined, but it does not get any thing done. It may pay off oneday, we have nice fonts on computers because Steve Jobs took a caligraphy class, for example.

I am very time poor, probably working more than 80 hours a week, but when doing a job that does not require much thought, I sometimes use that time to think about what I am going to do when I get a chance to make a print. What is the best approach is to solving an actual problem that I face. I think you will find that Stephen Hawkings thought is very disciplined and focused. Making progress requires discipline and focus.

 

[Bob Carnie]

Making progress in my world is never letting hold of an idea and going back to it whenever I can. I have been watching Chris for awhile and admire what he is attempting, he is digging very deep and sometimes his questions look very chaotic, but in the end I believe he will have a wonderful grasp on photography printing in all its forms.