Simon Ubsdell
6
COW Coins
Forum Replies Created
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[Spencer Tweed] “Believe it or not, you can use the techniques in that tutorial to get your blurry key ???? It’s actually the same problem – you’re just trying to get a “soft key”. Don’t take the tutorial too literally, just see how you can apply the techniques to your footage.”
Interestingly we looked at implementing this concept in Hawaiki Keyer 4.0 and had it working pretty well, but then figured it was probably a feature too far for most users.
Maybe time to revisit it for the next version.
Simon Ubsdell
tokyo productions
hawaiki -
Could you post an example of a shot you are trying to key?
Perhaps that will make it easier to recommend a method.
Blurriness is really just another form of transparency, in terms of how you want to approach the key. That means that you need to be as gentle with it as you possibly can.
Perhaps your keyer is not giving you enough control? Which one are you using?
Simon Ubsdell
tokyo productions
hawaiki -
[Stephen Smith] “The last time I did it it ended up keying most of the blurry edges away and then I had to re-blur them.”
Why did you key out the blurry parts? Was it because the key was too noisy? Or was there some other reason?
The general idea, if your source footage is of good enough quality, is to pull a nice soft key that includes things like motion blur and out of focus areas. You should not have to compromise on those.
That said, every really good key tends to be composed of a series of “patches” that treat each area of the frame in the best possible way.
The notion that it’s possible to have one key that fits everything is one to be avoided at all costs – unless you’re in a tearing hurry and you don’t have time to worry about the quality of the result.
Simon Ubsdell
tokyo productions
hawaiki -
[Spencer Tweed] “Check out this awesome video from Andrew Kramer covering this exact issue: https://www.videocopilot.net/tutorials/advanced_soft_keying/“
That tutorial, although excellent, has nothing to do with the question posed.
It’s about keying reflections, which is a very different issue.
Simon Ubsdell
tokyo productions
hawaiki -
Shoot with the best possible camera you can lay your hands on.
Budget cameras have crazy amounts of boiling sensor noise which means they are a nightmare for keying soft focus areas (and reflections and fine hair detail, etc.).
If you are stuck using a budget camera, use a decent denoiser to calm down the temporal noise. Neat Video does a good job but there are other workable solutions.
Denoise only the matte not the foreground for best results.
Simon Ubsdell
tokyo productions
hawaiki -
If you add a negative value to a positive value you will get a subtraction.
The chances are that the element you are trying to add has negative values (in the deep blacks at the edges), i.e, pixels that are below zero.
Hence the darkening effect.
Simon Ubsdell
tokyo productions
hawaiki -
[Bill Davis] “I freely acknowledge that you came back into the discussion subsequent to your initial post, and made it SUPER clear that you were NOT saying X was flawed. “
Thanks.
[Bill Davis] “Instead of saying from square one “I don’t get what APPLE is trying to do here.” The messaging that started to catch fire was that X was once again flawed for professional use. “
One final clarification:
I explicitly and clearly labelled my initial video as a “Mystery” – specifically, “Apple FCP X 10.4: The Color Wheels Mystery”.
And I concluded it by saying (almost verbatim): “I don’t get what Apple is trying to do here.” Specifically I said: “I just don’t understand it”.
I still don’t know what Apple are trying to do and I don’t pretend to.
Who steals my purse steals trash; ’tis something, nothing;
‘Twas mine, ’tis his, and has been slave to thousands;
But he that filches from me my good name
Robs me of that which not enriches him,
And makes me poor indeed.Simon Ubsdell
tokyo productions
hawaiki -
[Bill Davis] “Simon presented it as simply “they should have simply divided THIS by THAT underneath this control – and they messed things up because they didn’t do that.””
I wasn’t going to contribute further to this discussion because I think I’ve more than outstayed my welcome, but I have to put down a marker here.
I did not at any point in any terms whatsoever suggest or imply, let alone state or “present”, that Apple have “messed up”, as you are explicitly saying here that I did.
On the contrary, I have throughout strenuously and repeatedly (almost to the point of tiresomeness) resisted any such suggestion whenever anyone (including you!) attempted to make it.
There is simply no doubt about this. It is a matter of unequivocal record.
May I ask you to retract this claim, please?
Yours amicably, S.
Simon Ubsdell
tokyo productions
hawaiki -
[Bill Davis] “Then Simon, please help me better understand this.”
I should probably reiterate what is at the heart of this problem and the reason Oliver and I thought it was worth investigating.
Whether you’re a professional colorist or just an everyday user of any color system, you absolutely do not want a midtones correction to dramatically affect your shadows and highlights.
The Color Wheels Midtones control operates much more like an Offset control than the Gamma control that it is unquestionably meant to be.
This is not helpful. And it is inefficient in practice.
I highlight the midtones correction because it throws into sharp focus an issue that ripples right across the entire implementation of the wheels.
Does that make the point clearer for you?
Simon Ubsdell
tokyo productions
hawaiki -
[Bill Davis] ” And that they are science based – not arbitrary or “bugs” in the sense they are mistakes that need correcting.”
I have said all along, despite all the talk of bugs, that this isn’t a bug, but nobody wanted to listen. (Just kidding, but seriously, it really, really, really isn’t a bug.)
It’s a decision. And there is an explanation for why it is happening. And Philippe’s observations do, in part, illuminate what is happening (but not I think in an especially helpful way).
But what we are seeing is nevertheless an anomaly. And an anomaly that is, in my view, not helpful to the actual user of the product, who after all is the most important factor in this equation.
I really don’t want to make this personal but I do need to stress that Philippe initially posted a remarkable comment on my YT channel to the effect that we were seeing the SMH color model in play in the color wheels, and I think I have conclusively shown that he was wrong about this. And of course he is now no longer espousing this view. We can all get things wrong and no blame attaches to him for having jumped to this conclusion.
The fact is that a midtones (gamma) correction absolutely needs to behave as if the zero and one values were the zero and one values that we see in the waveform monitor. This is a fundamental requirement to make grading adjustments manageable in the real world. (I tried not to complicate my account of this and consequently some might argue that I was guilty of an over-simplication, but for practical purposes, I was not.)
The Color Wheels do not conform to this requirement, as I hope I have conclusively shown.
The fact that they do not conform is most emphatically not an indication that Apple have adopted an exciting new color model that is of unique benefit to the user.
If you force my hand, I am going to have to say that what they have done is poor practice and very unhelpful to any and all users.
But again, it’s not a bug. So please, please, please stop using that word.
Simon Ubsdell
tokyo productions
hawaiki