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I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?

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Chris Tomberlin
I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 20, 2012 at 9:31:27 pm

Bueller? Anyone?

Blackmagic, why can you make a 2.5K camera for $3K, totally redesign the Resolve interface (for free) but can't put one little line on the Ultrascope display??

Seriously, I love your stuff. I'm a big fan. But it would honestly be very helpful to have this feature.

Any others who would like to see this please say so.

Chris Tomberlin
Editor/Compositor/Owner
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Robbie Carman
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 20, 2012 at 10:29:18 pm

+1 on this. There are lots of things to be desired on the Ultrascopes. I sold a set of Omniteks because I was using about 10% of what they could do and while I haven't been hugely disappointed the omniteks were obviously better. I really like the ultrascopes but I bar, flexible views, true gamut scope (i.e tek diamond/harris eye) are some of my requests.

Robbie Carman
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Juan Salvo
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 20, 2012 at 10:56:20 pm

I sound like a freaking spokesnerd but... Scopebox.

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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 20, 2012 at 11:04:40 pm

Juan,

I've looked at Scopebox and it may be a solution, but I already have an Ultrascope and computer set up to run it.

SEEMS like all you'd have to do to add an I bar to Ultrascope is literally modify the vectorscope display graphic file to include an I bar line.

Chris Tomberlin
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Juan Salvo
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 20, 2012 at 11:11:55 pm

That's true. You might be able to do it yourself. I'm sure there's a png file somewhere in the app package. The scopebox suggestion was more for Robbie with his additional request. Most of which are elegantly handled in scopebox.

Given that the ultrascope GUI is fixed, you could even just put a thin piece of tape on the display screen. ;-)

Personally never use an I bar anyway so I don't really miss it, but it wouldn't get in my way if they added it.

Online Editor | Colorist | Post Super | VFX Artist | BD Author

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diego delanoe
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 1:03:41 am

Would n´t Scope Box make Da Vinci run slower, as it is using the same GPU? The same as when using the built in scopes from Davinci.
Sorry for my ignorance, but what is the I BAR?

THE PANIC PROPAGANDA


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Juan Salvo
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:51:28 am

You wouldn't & couldn't run either scopebox or ultrastudio on the same host system as resolve. You have to run either of them on their own box.

The I bar, is a line drawn over a vectorscope between the red and yellow vectors meant to indicate where human skin should fall.

Online Editor | Colorist | Post Super | VFX Artist | BD Author

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Danny Scotting
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 10:07:16 am

Who's human skin?
Mine? Yours? Barack Obamas? Dolly Partons?

Seems a bit silly to me to need one!

Danny Scotting - Senior Digital Colourist


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Ola Haldor Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 10:26:12 am

Whatever flavor your, mine or others skin tones are, they magically happen to appear along the same line. I don't see anything silly about it. It's there for guidance, to help us make better decisions.

Of course skin tones won't be pitch perfect along that line all the time after the grade is set. Skin tones are hardly ever the same in two different lighting conditions anyway.


So if you don't like the idea of that line, I bet BMD would be kind enough to make a button for you to switch it on or off.


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Sascha Haber
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 11:16:22 am

Yep

A slice of color...

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diego delanoe
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:24:52 pm

So you need anotehr computer just to ake ultrascopes run? Is that because Da Vinci does n´t let other software monitor live at the same time? Would it be the same for Pocket Ultrascopes?
Thanks

THE PANIC PROPAGANDA


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Margus Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:33:01 pm

Pocket Ultrascope also needs computer.

Just different one.

Scope takes up machine in a way that it will not work in Resolve machine.

You will love separate scope machine. Trust me.

--

Margus

http://iconstudios.eu

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brandon thomas
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 3:03:37 pm

being able to select which scopes show where would be fantastic.
Being able to resize/expand certain scopes.
Gamut scope.
RGB Histogram for grins.


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Lee Niederkofler
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 10:06:24 am

+1 for I bar and robbies requests!



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Margus Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 10:23:03 am

You should post this to BM main forum i bet ?

--

Margus

http://iconstudios.eu

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Dean Manion
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:04:17 pm

I (in-phase) and Q (quadrature) are old analog throwbacks and actually have nothing to do with skin tone at all. These signal references are merely a tool for determining if the original color subcarrier modulation of the NTSC signal was conforming to its phase and amplitude standard. I and Q are just like an X and Y axis for a vector scope signal presentation. The skin tone position on the vector is only coincidentally in the same area as the I axis, depending on the skin of course. I prefer to use my eye.


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Gabriele Turchi
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:31:28 pm

a gamut window and possibility of have larger windows would be fantastic : for instance i don't need the audio window and that takes zoo much space , also i think the windows cold have thinner canvas (to leave more room for the actual scope )

g

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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:46:28 pm

[Dean Manion] "I prefer to use my eye."

Your eyes will lie to you. A scope tells the truth.

Chris Tomberlin
Editor/Compositor/Owner
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Margus Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 2:49:22 pm

with scope you can match shots more accurately

--

Margus

http://iconstudios.eu

DaVinci 8.2.1 OSX 10.7.3
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Dean Manion
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 4:35:10 pm

"Your eyes will lie to you. A scope tells the truth."

There are many truths (or skin tones). Some prefer to measure, others prefer to feel, and still others prefer a good glass of scotch. Me? Depends on my mood. It's all relative - color grading, skin tones... even scotch. In a relative world, what is truth?


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Mike Most
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 3:54:47 pm

True, of course (regarding the I and Q axes). In the PAL world, the U and V axes represent the same thing (they happen to be coincident with the X and Y axex, so this isn't as obvious). But that fact likely won't stop people here from coming up with their own explanations as to what those things represent.


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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 4:44:10 pm

Ok, so I've figured out how to modify the vectorscope display (or any other scope display I suppose) in Ultrascope. I'm not saying YOU should do it but it IS a relatively simple matter. BMD could literally make this addition in about 5 minutes. If you're interested I can describe the process off list.

chris_at_outpostpictures.tv

Chris Tomberlin
Editor/Compositor/Owner
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Juan Salvo
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 6:06:52 pm

Was it a PNG in the app package?

Online Editor | Colorist | Post Super | VFX Artist | BD Author

http://JuanSalvo.com


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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 6:30:34 pm

Yup. A little more involved on the PC version...

Chris Tomberlin
Editor/Compositor/Owner
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Margus Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 21, 2012 at 7:29:23 pm

i bet there may be legal thing why the line is not there ?
as in tech sense it seems simple to do.

God knows who has patented it like some other every day stuff that you can not use without
paying licenses.

--

Margus

http://iconstudios.eu

DaVinci 8.2.1 OSX 10.7.3
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Mike Most
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 4:31:43 pm

It's not there because its only real purpose is to define where the subcarrier should be on a standard definition, NTSC video signal, along with another axis that is 90 degrees opposed to it (the Q axis). It has no relevance in an HD world, regardless of what people here seem to think it is. The notion that it's some kind of "flesh tone indicator," or that its actually called an "I-Bar" is something that people who have no idea what its real purpose was simply made up. The fact that people here are seriously discussing it in those terms is, frankly, a bit distressing.


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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 4:35:20 pm

It doesn't really matter to me what you call it - if it is a tool that helps us make better decisions then why not use it as such? I understand that it is a throwback, but it is still a useful one in the HD world even if it is used for something other than its intended purpose, IMHO.

Chris Tomberlin
Editor/Compositor/Owner
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Mike Most
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 6:00:57 pm

If you believe that flesh tones should always look the same, or that they are not dependent on other aspects of the image, or that they're not relative to the environment, or that they should always be in the exact same place on scopes, then what you're describing ends up being a technical crutch that will often make your images look less natural, not more natural.

Everything in terms of color is relative to what's around it. A flesh tone in perfect white light is quite different than the same flesh tone in a warmly lit room or in cool moonlight. It is different in a lit part of a room than it is in shadow in the same room. You don't need a specific marked point on a vectorscope if you understand all of that, and you don't need a specific marked axis if you understand what the vector display is telling you. Calibration - the purpose for which the I and Q axes were placed on a standard def vector display in the first place - is one thing. A confirmation of what's in a real world image is another, and for that, you basically want the vectorscope to tell you relative values, and black and white balance. Flesh tones are going to land wherever they land depending on the scene lighting and the scene content. You don't grade based on a vectorscope (except as an aid for balance, as I mentioned), you grade based on an accurate calibrated display, which is the only way to judge relative color. The best pure colorist I know (and I know most of the best in the industry) almost never looks at scopes. In fact, he often doesn't even have them turned on. But his monitoring is checked and calibrated every day, sometimes multiple times during the day, to ensure that what he is seeing is accurate.


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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 6:48:43 pm

Well, this is the last reply I have on this so if you respond you'll get the last word.

I agree with what you're saying. I realize that skin tones and everything else in an image is relative. I'm not suggesting that you should put green in the green box, red in the red box, flesh tones on a particular line, etc. It is helpful however to have a scientific measure of an image if you don't have the luxury of owning a $40K monitor and minions to calibrate it every day.

If you'll search this forum, you'll see that this same request was made a year ago by other people who also think it could be a useful tool. My original post was a little chastisement to BMD for not responding to customers requests for a feature. If you (and they) feel that request is a silly one, then to each his own, and those of us who would like to have this feature can look to other solutions.

Peace.

Chris Tomberlin
Editor/Compositor/Owner
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Ola Haldor Voll
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 7:50:01 pm

I might be distressing. What I said earlier is what I've learned from one or several paid video tutorials or even books, not something I've magically figured out by myself "EUREKA! This must be what it's for!". Maybe it's rumors and BS - but hey - it helps me. Can't say I've had much complains about bad skin tones, except producers and directors not noticing how different skin tones can be just as they are. Some are more red, some are pale..


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Juan Salvo
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 8:21:40 pm

While its true that the i/q/x lines on vectorscope date back to the old analog days, I don't think it's a coincidence neutrally balanced skin tones falls along that line. I think it was done intentionally. If you just wanted a reference point for phase any old color would do. But what's that most videotaped tone if not skin? We literally film some human skin in almost every single shoot. We love looking at ourselves, so why not use our own pigment as a frame of reference?

And if it's a made up thing, it's spread far and wide. Even made it into apples documentation for fcp7.

http://documentation.apple.com/en/color/usermanual/index.html#chapter=8%26s...

I'll refer you the section entitled I-bar.

I'd add that I and I think many others, don't use this as a guide. Skin tone is subjective and the over all balance of the scene would affect the way skin should read. But people doing so aren't mistaken or misguided.

Online Editor | Colorist | Post Super | VFX Artist | BD Author

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Mike Most
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 23, 2012 at 9:46:14 pm

While it is true that the i axis (it's NOT "I-bar," that is a term that whomever wrote that Apple document made up and a whole lot of other people obviously took as some kind of gospel) falls in the area of the display that flesh tones often fall into, one has little to do with the other. It is simply based on the limitations of bandwidth, and the desire when the NTSC system was first introduced to allow for more information in the orange/cyan axis than the purple/green axis, due primarily to the fact that human vision has more acuity in those colors. By skewing the color difference signals toward the orange/cyan axis (it's actually 33 degrees rotated from the X/Y axis, so if you want to mark your own I-axis just rotate it -33 degrees with respect to Y) they created a situation where the purple/green axis could be more severely bandwidth restricted, since it was "less critical" in terms of the way the human visual system perceives images. In other words, the presence of the I axis and the location of common Caucasian flesh tones being in a similar area on a vectorscope is not completely a coincidence, But it is also the case that this wasn't done to give some kind of flesh tone guide, it was done because that's the way human vision works. And I would also point out that in the PAL color system - used in more than 80% of the world for over 50 years - the I and Q axes do not exist (they use the U and V axes, which correspond exactly the the X and Y axes). So an assumption that the I axis is there specifically for flesh tones - in particular Caucasian flesh tones - is incorrect, based on equally incorrect information printed in an Apple document.

There are truths and there are untruths. Just because Apple says something doesn't make it true, even if they are the richest company in the world. And asking the Blackmagic engineers to put an axis on their vectorscope display that has no relation to anything other than standard definition NTSC video, simply because you happen to like seeing it, is essentially asking them to be incorrect in terms of engineering. If you want to see an I-axis, draw one and use it if you like. But you shouldn't demand that engineers do things that are technically incorrect or effectively obsolete, as that is not their job. That's all I'm going to post in this thread, because it's clear that people are going to do and think whatever they want whether it makes any technical sense or not, and regardless of the facts.


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Alexis Hurkman
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 28, 2012 at 3:05:09 am

I hate to chime in late to a thread that appears to have reached its natural conclusion, but I missed it earlier, and since Apple documentation has been brought up, it seemed interesting to add another perspective, since I wrote the passages under discussion, and it may shine a light on both some design decisions in FCP and Apple Color, and how terminology gets coined and, right or wrong, disseminated. My apologies in advance for the length of this missive.

When FCP 3.0 was in development, the then-new color correction tools and video scopes being added were brand new to the majority of desktop video editors, and the engineering team was working to try and make this unfamiliar paradigm of lift/gamma/gain style controls and the accompanying scopes comprehensible to a new audience. It was a deliberate design decision to include one half of the in-phase axis indication line all by itself as an indicator of the general hue of skin tone, since to my knowledge the not-so-coincidental dual use of that indicator had been a documented rule of thumb of videoscope use for years prior.

In an effort to make the purpose of this line more transparent, I and some others decided to call this the "Flesh tone line," a decision I now somewhat regret as it muddies the history of this indicator; and yet as this was the only one of the in-phase and quadrature lines that the team elected to draw upon the FCP vectorscope, I stand by the decision as it made immediate sense to the new user, and the purpose of this indicator as intended had nothing to do with signal alignment, and everything to do with providing a flesh tone signpost to people new to reading scopes.

Regarding the "I-bar" terminology, this was the term I decided upon when writing the Apple Color documentation, as I expected a more experienced audience would appreciate an acknowledgment of the original purpose of this line. Also, the Color team implemented all four in-phase and quadrature indicators, so it seemed appropriate, "I" for in-phase, bar because it was a line.

I did not make this term up; after scouring different terminology from various sources, I found and settled on "I-bar" as the shortest term for purposes of documentation (try typing "i-axis indication line" ten times fast). Unfortunately, I can't cite my source anymore as this was years ago, but nobody in a position to offer a technical review of that manual, nor any colorist who's done either technical or casual reviews of books I've written since, has ever informed me that "I-bar" is wrong, and I've been using it consistently ever since. If, in fact, it turns out that my deadline had made me delusional and "I-bar" was the fevered ravings of a caffiene-addled technical writer, then I still stand by it since it's less to type and is a fine abbreviation, but I cannot in truth take the credit.

I've discussed the history of the I and Q axes with many folks over the years, and while it's true that the engineering reasons behind these indicators have nothing strictly to do with flesh tones, my personal feeling is that the coincidental utility of the in-phase indicator's position has, over time, come to outweigh its original purpose, and in fact I would consider the "I-bar" we're currently referring to as a new thing that coopted the old, sort of like Easter coopting an earlier collection of various pagan celebrations.

To clarify, I would never and have never suggested that this line is a strict guideline for human hue. In my "color correction handbook" I wrote and illustrated more pages then my editor may have wished about the subtle variations of human skin tone, and how the in-phase indicator under discussion is merely a general signpost; like speed limits, nobody follows them exactly, but it lets you know you're around what you ought to be doing.

Lastly, I've used scopes that have an I-bar, and I have a very expensive scope that doesn't (in HD mode, as has been pointed out), and while I still think it's nice to have, its absence has never hampered me from delivering attractive skin tones to my commercial clients. However, given the choice, I'd like to see this indicator as an option for folks who like it; in fact, I'd love to see someone develop the option for multiple programmable vectorscope indicators at user-selectable angles, but then I'm a bit nutty for options. The hue that, in NTSC, is represented by the I-bar can certainly be mathematically translated into the same hue in HD color space, and I see no reason why that wouldn't be useful or appropriate, if it's documented clearly that this is no longer in-phase, but in fact an analogous flesh tone guidepost that can be turned on or off.

I would suggest that video scopes at this point are simply software, and it should be no sin for developers to add new features of utility to users and to label them clearly. I'm fond of pointing out that the days of fixed ground glass graticules are over, and it would be nice to see developers find more things to do with scopes for both basic and advanced users then to simply replicate functionality from analog, trace-drawn CRT technology.

http://www.alexisvanhurkman.com | http://www.correctionforcolor.com


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Chris Tomberlin
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 28, 2012 at 4:01:55 am

Thank you for commenting on this and providing some additional insight. It makes me think that perhaps I'm not suggesting something ridiculous after all by requesting BMD add a little line (that I can choose to ignore or not) as an option.

Thanks

Chris Tomberlin
Editor/Compositor/Owner
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Dmitry Kitsov
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 28, 2012 at 7:51:30 am

I am sorry it is not entirely clear to what you meant?. Did you mean that the human vision has more acuity in Orange /Cyan or in Green/Purple?


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Mike Most
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 28, 2012 at 4:06:38 pm

Human vision exhibits less spatial acuity in the green/magenta axis than it does in the red/cyan axis. When the YIQ system was developed, this was taken into account, as they were trying to use the available bandwidth in the most efficient manner. It was thought that by skewing the color difference axes, the one that represented the green/magenta axis could be more heavily filtered since some of the information in it would be superfluous based on that fact. In practice, though, most NTSC transmissions wound up being encoded as YUV anyway, but the I and Q axes remained as an engineering setup guide regardless, and are thus present in the standard SMPTE color bar display for that system.

All of this is a lot of geek talk, though. Alexis has basically confirmed that the original meaning of the I and Q axes was co-opted to mean something completely different in the world of Apple. Kind of like whispering something to the first person in line, then having it repeated to 20 other people in line, only to have it come out of the 20th person as something completely different than what it started out as. What bothers me is that engineering, by definition, is something that usually deals with absolutes, not opinions. Mathematical equations and human perceptual studies don't change, and neither should the definition of things based on those criteria, even when it's done in the name of making things simple for the masses, which is Apple's stock in trade. No matter how complex and meaningful something is, Apple can present an "i-version" of it. Hence why we have iMovie (editing for non-editors), iPhoto (color retouching for non-artists), iWeb (web site design for non-designers), and numerous other things. And, at least in part, I guess it's why they apparently invented the "iBar," to allow a flesh tone guide for non-colorists.

At least that's the way I see it in my more cynical moments. ;-D


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Joseph Owens
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on May 28, 2012 at 8:14:45 pm

@Mike.

No cynicism involved, and extremely happy to see Alexis chime in on this. So few of us have living memory of composite baseband analog that we live in danger of reverting to a system of superstitions. "When you believe in things that you don't understand...." thank you Stevie.

The In-Phase axis is a great reference, no doubt. Back in the day of setting up quad playback, where the matrixing varied from machine to machine and trim pots, sometimes the only reference we could really count on was placing the red "dot" on the 2% box, and everything else would just have to fit where it landed. Too bad. It was the closest to "fleshtone", whatever that is, and resulted in the fewest client objections. Its actually too bad that the I/Q flags are 120 degrees from reference and that the -I burst is not actually set up to fall on its positive axis. but anyway...

As you say, In-phase and Quadrature are no longer relevant, the same as subcarrier and RS-170A, since the advent of CAV and then 601 and 259M. For those who have outboard scopes that show axes, you will also have to come to terms with the the fact that even when those guidelines are shown, they are not actually in 90 degree quadrature anymore, oweing to the difference in matrix calculations, especially between YIQ (no longer in use) and Y'CbCr, which is now ubiquitous. It does make it rather difficult for the manufacturers to be both mathematically rigorous and sympathetic to the artistic community at the same time.

As to the cyan/red and green/magenta bandwidth-limiting strategy, while it is true that the spatial frequency response of the human eye has that characteristic mentioned, from an engineering standpoint, the reality is that you can "borrow" bandwidth from how the channels are constructed. One upshot of how Y is composed, (mostly green) is that you can really knock it off in the chroma channel... because its already there waiting to be re-constituted when you make Y/I/Q back into R/G/B for display.

There are of course three channels in vestigial-sideband composite analog to cope with the historical 6MHz total bandwidth allotted to terrestrial broadcasting. Early videotape recorders needed to achieve a relative head-to-tape velocity of about 90 feet per second to achieve the response necessary. That's just electromagnetic physics. Anyway, the three components, which is what you need to re-construct any color signal, whether its R/G/B, or H/S/L or whatever, can have different characteristics depending on the transmission. In Y/I/Q, Y is luminance, and saturation and hue are encoded in the phase and magnitude of the I/Q vectors. NTSC engineers were looking for ways to buy the best response with maximum efficiency. Luminance was pretty much mandated for backwards-compatibility with black & white -- and interestingly enough, if you look at a bell-curve of human electromagnetic band response, (we see between, but not including, infrared and ultraviolet), right in the middle is green/yellow. So it should not come as a surprise that NTSC "Y" is a matrix of about 70% green, 20% red and 10% blue (numbers inexact for the mathematically-challenged). The immediate technical bonus is that your main signal can be nearly represented correctly with one channel and it gets the lion's share of bandwidth. It is also true that humans don't really need a lot of detail in the color component of vision since we mostly interpret the world in terms of contrast. So the I and Q components can be highly bandwidth limited, since we just don't need it, and you can re-modulate them onto the top end of the luminance signal since the energy distribution will also allow that. NTSC (Color) is really an astonishing achievement for its time.

So two things: If the flesh-tone area was really THAT important, why wouldn't it be made into a major axis (maybe adding some kind of dotted brackets for some kind of subjective variation)? and, having skipped over two or three years of sampling and communications theory, Fourier analysis, Nyquist theorems etc, can modern media practitioners survive without knowing and appreciating how some of the tools and methodologies evolved almost naturally as the children of necessity?

When I think about it, however, the Inphase axis and I-Bar (awareness and understanding) may also be a line of demarcation of another type... (we? us? old farts who know how things actually work and they? the young ones who don't actually care?) Now that's cynicism.

jPo

You mean "Old Ben"? Ben Kenobi?


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Dmitry Kitsov
Re: I bar please in Ultrascope. Or Resolve. BMD, come on, how hard it this?
on Jul 29, 2012 at 7:39:06 pm

Could you elaborate on how to do so in a PC version?


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