Am I missing something?

[Roy Sletcher]

Now that you‘ll taken out that darn checker board this thread could go on for years.
I see with my eye and use my brain to define what exactly I am looking at.. The Hat..

Look at the checker board!
Think of a problem.
You are getting t-i-r-e-d.
You are feeling s-l-e-e-p-y.

Get the idea? - works every time, and I always get a good nights sleep.

RS

 

[Paul Verizzo]

Thanks, guys. Interesting stuff. I'll offer up/ask back the following:

1. My definition of "Perfect black" means either the subjective sense of without hue, or objectively, a measured gray scale rendering of equal parts R, G, and B. At 18% reflectivity, that's 128-128-128.

The Canon Pattern Print allows a very fine setting for variation, so that after printing one has very subtle shifts in coloring. As little as +/- 3 in manual

2. I'm not in the habit of reducing the gamut! In the end, we are all limited to what the printer can print, anyway.

Ray, you always have interesting things to say. I watched that video; do you realize what "the take away" of it is? (Paraphrasing) There is no objective way of viewing our environment. Pretty much along the lines of what I'm saying. In the end, it's our lying eyes, brain, and experiences.

I reiterate the phenomena of Fuji Velvia film. Since the 1930's, all the film companies struggled to make slide films that were as accurate in color translation as possible (plus-minus things like philosophy; Agfa was always known for its warmer films.) Fuji comes along with Velvia, rather saturated in its spectrum, and the stampede was on. Meanwhile, all those companies and photographers that insisted on a realistic interpretation were left standing around looking at each other wondering what happened. Subjectivity is what happened! One still had to understand one's tools; Velvia wasn't exactly a good portrait film!

 

[Łukasz]

There is no objective way of viewing our environment. Pretty much along the lines of what I'm saying. In the end, it's our lying eyes, brain, and experiences.

Yup, human eyes aren't objective
But we have some equipment and workflow for color measurement.
ICC profiling is intended to make predictable results, by ensuring use of central fixed colorspace - eg. CIE Lab. Fixed colorspace is same thing for measuring color like meter/inch sample for measuring length.
ICC profiling is not to make image look warmer or colder in the way like analog films does (or to improve the subjective visual impression). It is a role for postprocessing.

Ł.

 

[The Hat]

OK you ‘ve got me thinking so I got a question for everyone, how can the step wedge on the bottom of these two prints have exactly the same values when both of them have been sent to the printer so differently ?

 

[Paul Verizzo]

Yup, human eyes aren't objective
But we have some equipment and workflow for color measurement.
ICC profiling is intended to make predictable results, by ensuring use of central fixed colorspace - eg. CIE Lab. Fixed colorspace is same thing for measuring color like meter/inch sample for measuring length.
ICC profiling is not to make image look warmer or colder in the way like analog films does (or to improve the subjective visual impression). It is a role for postprocessing.

Ł.

Absolutely no argument from me, believe it or not. I do get that goal.

There are absolutely times and places when that should be the goal. Especially in matters scientific.

But I maintain that some 90-95% percent of all images made starting in a camera, presumably, that the few that are printed nowadays, are not thought "better" or "worse" by most eyes. Especially if you stare at it for half a minute. Your brain auto-corrects what your processing botched.

Probably not one person on the street in a thousand knows what a gamut is, nor could they tell a high gamut print (most subjects) from a low gamut. And if you showed them two prints, same everything except one started on Fuji Velvia, and the other on, oh, Kodak Ektachrome, they will pick the Fuji print almost every time.

Canon even has a printer setting to take advantage of this quirk of human seeing. It's called "Vivid," and it jacks up the blue and green saturation, leaving (presumably Caucasian) flesh tones alone.

Humans, always the ultimate end user of a print or image, are inherently subjective and emotional. Homo Sapiens Sapiens, "thinking man?" I, dare I say, "think not." Perhaps Homo Sapiens Consecteturer. ("emotional man", if I'm to believe the online translator.)

I have not infrequently found an image that failed the perfection test to be much better as art. Grabs you more. That old devil and his cousin, emotion and subjectivity.

 

[Paul Verizzo]

OK you ‘ve got me thinking so I got a question for everyone, how can the step wedge on the bottom of these two prints have exactly the same values when both of them have been sent to the printer so differently ?

I downloaded that image from Kodak a number of years ago. It is their digital version. All the B&W steps are of equal RGB value. The 18% gray circle is equal parts, 135, IIRC, of the primaries. I stretched the tablet levels so that they covered the full 0-255 range. I then made a monochrome of the same image and combined them.

So, yes, the test strips should be exactly the same.

 

[RogerB]

OK you ‘ve got me thinking so I got a question for everyone, how can the step wedge on the bottom of these two prints have exactly the same values when both of them have been sent to the printer so differently ?

These two prints were sent to a "virtual printer" that has perfect greyscale reproduction but very imperfect colour reproduction. The same printer was used for the right-hand image in the PDI set. Such a printer is theoretically possible, albeit unlikely. It just tried to demonstrate that a colour space can have perfectly linear greyscale response without perfect colour response. I thought that addressed Paul's original question.

 

[Paul Verizzo]

How many angels are dancing on the head of the gray scale circle?

I read through this and other discussions, that no matter how accurate, how "perfect" a step in the process is, there's something inaccurate and "imperfect" about it. Which is my whole point. You do the best, go 90-95% of the way rather easily.

The imperfections start immediately at the front end of the process, whether film or CCD. Even a RAW image is processed, don't forget. Perhaps the film gets scanned, oops, more imperfection, and then perhaps "reverse scanned," to make a color print via laser. Or if digital, there's dealing with monitors. Not just yours, but someone else's if you send them a file. And then off to the printer, a hodge podge of technologies that do amazing service for us. And then, finally, our eyeballs, brains, and even our experience, inform us with with our own interpretation. Which could be a long, long way from what was there when the shutter clicked.

As the lecturer in the video said, paraphrasing, "There is no objective way to discern reality."

 

[RogerB]

How many angels are dancing on the head of the gray scale circle?

I read through this and other discussions, that no matter how accurate, how "perfect" a step in the process is, there's something inaccurate and "imperfect" about it. Which is my whole point. You do the best, go 90-95% of the way rather easily.

The imperfections start immediately at the front end of the process, whether film or CCD. Even a RAW image is processed, don't forget. Perhaps the film gets scanned, oops, more imperfection, and then perhaps "reverse scanned," to make a color print via laser. Or if digital, there's dealing with monitors. Not just yours, but someone else's if you send them a file. And then off to the printer, a hodge podge of technologies that do amazing service for us. And then, finally, our eyeballs, brains, and even our experience, inform us with with our own interpretation. Which could be a long, long way from what was there when the shutter clicked.

As the lecturer in the video said, paraphrasing, "There is no objective way to discern reality."

Paul, your original post asked "....if a monochrome portion of a test image is "spot on," would not the color portion be, too? For instance, the Kodak model image here, http://1drv.ms/17BXQ1D has a small circle of 18% gray scale." The simple answer is "no - not necessarily". I have tried to explain why it is not necessarily so, which is unsurprisingly a slightly more complicated answer. My answer has nothing to do with seeking perfection - it is just an explanation of why the answer to your question is "no". I thought that it might help people's understanding.

It seems that you keep asking questions solely to be contentious, without any real desire to find an answer. Whatever answer you get you simply revert to your "everything is imperfect and beyond our control and people prefer imperfection anyway" rant. You will be pleased to know that I have had enough. I will no longer feed your rant machine.

 

[Paul Verizzo]

@Roger and others. No, I'm not trolling or trying to be contentious. I've agreed that there are times in life to be "perfect." That Ansel Adams was a great photographer more so because of his technical perfectionism than the image itself. (BTW, he died not long after digital cameras, the first ones, were starting to come out. He though the whole idea was pretty cool and very intriguing.)

In my fading tests, if I didn't have an unfaded comparison image, variations that I'm sure are way outside of what an ICC profile would pinpoint are hardly noticeable in the color portions. Most non-graphics type people wouldn't ever notice. But over in the B&W sections.....wow! So obvious as the inks don't fade in lock step.

Anyway, believe it or not, I'm appreciative of all of your's time and attempts to convert this heathen, even if I didn't, pardon me, see the light.