As a Shake user, I learned to love the explicit image processing organization that node-based compositing afforded. Never mind trying to figure out which precomp corresponded to what part of the composite; one look at a well-organized node tree and you can see exactly what’s going on.
Furthermore, once you get the hang of using nodes, you can begin to work out your order of corrections in advance in a classic programmer’s tactic; flowchart your way through a complicated series of operations in order to think them through, except in this case, the flowchart is also the result!
I’ve been discussing node based operations with my friend and colleague Robbie Carman, who’s another DaVinci Resolve beta user, and in the process thought that it might be interesting to share some of my favorite operational aspects of Resolve’s method of node-based correction organization.
#0—A Quick Orientation
Similarly to the node-based Color FX room of Apple Color, node-based corrections in Resolve aren’t for the actual compositing of multiple images with one another. They’re for organizing and combining the different corrections you want to make to your image. Before I dive in, here’s a quick overview of how Resolve uses nodes.
Every clip has a corresponding set of corrections within a “Clip” tab. This tab is Resolve’s node view, where each correction is represented as a rectangular node, with a single input and a single output, which can be seen as little yellow dots to the left and right of each node.
 A node tree in the Clip tab of DaVinci Resolve The flow of image data goes like this: The left-hand bar is the source image on Disk. Connection lines (with small directional arrows) feed image data to the first node in the tree, represented by a thumbnail showing what that node is up to (literally; the correction performed by each node is represented by its tiny thumbnail if your eyes are sharp enough). Connection lines also connect each node you use to one another, feeding image data down the line until the last node is connected to the right-hand bar, which represents the final output.
#1—Organizing My Image Processing
In a very real way, a serial cascade of image processing nodes like that shown above is like a stack of filters in After Effects, Final Cut Pro, or Avid. The output of the top filter feeds the next one in the stack, and so on until you reach the bottom.
You can think of nodes as a similar series of image processing operations. More poetically, you can think of nodes as individual waterfalls along a stream of image processing. Each waterfall alters the flow of data, which in turn feeds the next part of the stream, until you reach the end.
The key thing to remember is that, depending on what type of image processing operations you’re doing, your order of operations matters, a lot. One of the most frustrating things about working in Color is the occasional instance where I discover my order of operations isn’t quite right, usually after I’ve done several corrections. For example, let’s say a primary correction (the first node seen below) blows out the highlights in the sky.
 Three nodes, a primary correction, a secondary sky operation, and a third primary for tweaking the color I don’t really care until my client complains, but then I can’t retrieve it using a secondary correction (the second node in the tree above) because the image data is already clipped. As a result, my secondary HSL Qualifier only succeeds only in creating a bizarre darkened area in the sky:
 Attempting to lower the level of the sky fails to retrieve clipped detail When using Apple Color, my solution in these cases has been to save the Primary correction to the bin, reset the Primary In room, open the Primary Out room, and apply the correction that I saved there, effectively swapping the PI and PO rooms. At that point I can use a secondary of some kind to lower the highlights before I boost the rest of the shot, and so I get to preserve maximum image detail.
In Resolve, this is an even easier operation. All I do is either add a node with which to perform a secondary sky isolation operation before my primary correction (or, if I’d already tried a later secondary correction with no success, swap the two node’s positions in the tree).
 Swapping the secondary and primary operations This allows me to isolate and duck the levels of the sky before boosting the overall levels of the shot in the next node. The result is smoother, more natural, and preserves all the image data that’s available, which is always a bonus.
 Lowering the level of the sky before boosting the whole shot preserves detail This gives me exactly what I need in terms of image processing organization. Now, I grant you there are several other ways of dealing with this particular scenario, but the point is that, using nodes, I control the order of operations, not the application.
Here’s the other nice thing—you can use as many nodes as you like to organize your grades. I like to keep significant operations within separate nodes, so I know where I need to go when I want to make an alteration. That means I might have one node doing a basic corrective grade, a second node adding a bit more warmth and contrast for stylistic effect (as I’ve done in node 3 of the previous example), and then a third node where I add a perhaps questionable alteration that was requested by the client, that I think they might backpedal on later. I could have done the entire series of operations within a single node, but by keeping these three operations separate, I’ve got more options regarding which aspects of the grade I want to continue tweaking, and which I can turn off entirely without affecting the rest of the grade.
#2—Serial and Parallel Organization
So that’s fun with serial node organization. However, Resolve also has Parallel node organization. This is another way of putting nodes together, so that instead of having a single long tree branch, you can stack up simultaneous corrections whereever it makes sense. For example, if you’re planning on using three secondary operations to affect an image at once, you could apply them as a serial operation, like so:
 A serial node tree, organized as a linear set of image processing operations Or you could apply them as a parallel operation, with three stacked nodes feeding a Parallel node.
 A series of secondary operations organized as a parallel node tree Resolve overlays the corrections to produce the result you’d expect, and the tree organizationally makes a lot more sense. However—and this is a big deal—the parallel node structure ensures that each secondary correction node samples the same version of the image. This is important, because I like…
#3—Choosing What My Key Source Is
This one’s easy. Remember I mentioned that the leftmost bar in the Clip tab represents the original state of the image? Well, if you’re adding a secondary operation via a parallel node structure, you can choose whether you want to pull your key off of the original state of the media, or from a particular node of the tree, simply by connecting that node’s input to the source you want to sample.
For example, suppose my look for the primary correction performed by node 1 results in a high-contrast, low saturation image.
 A high-contrast, desaturated grade is the starting point If I wanted to add a second node and use HSL qualification to boost the color of the dress, I could do the simple thing and add another serial node:
 Adding a serial node for HSL Qualification Unfortunately, the image is so desaturated and stylized that it’s really difficult to pull a decent key. Here’s an example of my first sampling click:
 Terrible isolation due to a poor source selection Even though node 1 is doing what you want it to, the result is that the image is in a crummy state to have to pull a key off of.
However, there’s a better solution, which is to use the parallel node structure described previously, connecting the input of node 2 that’s pulling the key to the media source bar, instead of the previous node:
 Pulling a key off the original state of the image using parallel node construction Now, using the original state of the media, it’s easy to pull a great key. Here’s an example of my first sampling click using this new node structure:
 A better key, sampling from the source media Now that we can get a better key, it’s easy to manipulate the color of the dress however we like, and then feed it back into the image.
 Adding color back to the image, after the fact So there you have it, complete control of image sampling, all through the power of selective node connectivity. I love me some nodes.
Image Credits
Photography by Kaylynn Raschke. Special thanks to Gal Friday and Sasha Nialla for modelling. Images excerpted from my new book, Color Correction Handbook: Professional Techniques for Video and Cinema.
Writing. Writing. Sleeping. More writing. The periodic grading gig interruption.
Yes, it’s “the last month of writing my book,” and just like every other book’s last month, it’s a round-the-clock marathon of typing, research, setting up example projects that look good and explain the topic at hand, screenshot-taking, and illustration making; all amidst a vague feeling that I should be getting more sleep.
And the periodic beer.
However, amidst all the toil, there are still magic moments, and today was the culmination of a plan I’ve long had to more fully examine and portray the possibilities of human skin tone (one of the chapters of the book I’ve put particular emphasis on). After I identified the list of complexions I wanted to document, photographer Sasha Nialla assembled a terrific roster of models, and with me playing client shot all of them under controlled lighting conditions, allowing me to show an apples to apples comparison within the book of the basic categories of complexion, for analysis and consideration.
 Photographer Sasha Nialla shoots our redhead sample subject. It's the sexiest science you're going to see... My personal criteria for how good a technical book I’m writing is, happens to be the same as that I use for screenplays—if I’m having fun writing it, then it’s probably turning out well. It eases my mind that I’ve been getting solid feedback from Joe Owens, who generously agreed to be my tech editor, lending his experience (and subtle humor) in the evaluation of my assertions and techniques. And I must give credit to Peachpit Press, and my editors Karyn Johnson and Stephen Nathans, for continuing to provide the time, encouragement, and editorial support to get things right. These damn books aren’t easy to make, and I’m glad that PeachPit has lent their support.
Furthermore, I’ve been getting terrific support from DaVinci (who also graciously let me into their beta for Resolve on OS X), FilmLight, Iridas, Assimilate, Quantel, Tangent, DSC Labs, X-Rite, Light Illusion (Steve Shaw), and of course various friends at Apple, alongside others I am to my shame forgetting. All of which has enabled me to meet my goal of creating a color correction handbook that is truly platform agnostic, and aimed squarely at the budding professional colorist (and the casual colorist who aspires to professionalism). If you’re a complete beginner, this book should orient you with a foundation in color theory and basic operations; if you’ve been grading for a while, this book may fill in some conceptual gaps, provide additional theoretical food for thought, and toss out some nice tricks that you might find useful.
My criteria for which applications to discuss in the book has been based on color control surface compatibility, on the premise that a) if you’re a dedicated colorist, you’ll be wanting to use one, and b) most grading applications that are dedicated to the task are compatible with one or another, either custom made (Resolve, Baselight, Quantel) or off-the-shelf (such as a JLCooper, Euphonix, or Tangent Wave surface). On the other hand, most of the techniques discussed can be implemented using Colorista, Final Cut Pro’s Color Corrector 3-way, After Effects, Color Finess, or any plugin with 3-way color balance, HSL Qualifiers, and Masks. No matter where you’re making your corrections, there’s bound to be some information that will be useful to you.
So that’s why I’ve somewhat fallen off the edge of the earth. I’m due to finish soon, and look forward to getting my weekends back, getting the book out to the public, and maybe doing a book tour or something and seeing what you folks think of it.
For a change of pace, I thought I’d toss out a small nugget of pure speculation (this time I’m really thinking aloud). However, in the event history proves me to be right, I thought it’d be fun to commit this thought to the internet.
I was originally going to rant about how much of a “#$%@ you” I felt the latest rev of the Mac Pro line is to the postproduction power-user. In fact, I was going so far as to compose an email to someone I know who might actually care, when for due diligence sake I decided to do a bit of research to find out just how far behind the specs of the Mac Pros are from our Windows and Linux workstation bretheren. In particular, I wanted to find out whether there was a better version of PCIe that we were missing out on.
Popping over to good ‘ol Wikipedia, I found the following nugget of information (emphasis mine):
The final specification PCI Express 3.0 has been delayed until 2011 and will be backwards compatible with existing PCIe implementations.[15]
So, the next major architectural update that will be useful to me (in the form of faster data throughput, faster GPU data pushing, etc.) isn’t going to be finalized until 2011.
Oh, and one other thing… I keep wanting faster FireWire. After all, FireWire 1600 and 3200 were announced back in 2008 as a response to USB 3, right? Well, here’s what Wikipedia has to say about that (again, emphasis mine):
S1600 (Symwave [23]) and S3200 (Dap Technology [24]) development units have been made, with the latter promising a consumer version by late 2010.
At the risk of sounding like an apologist, it seems entirely plausible that maybe, just maybe, somebody is waiting for PCIe 3.0 and FireWire 1600/3200 to become finalized/implementable before committing a ton of resources to redesigning and retooling the Mac Pro in a significant way. At least, that’s what I’d like to think.
And while that still doesn’t excuse the lack of USB 3, 10-gig ethernet, or port-multiplied eSATA (okay, so that’s really wishful thinking), I suppose I can understand. I mean, why do a bunch of redesign work when next year you’re just going to redo it all from scratch?
Guess we’ll see…
When Stu Maschwitz started beating the drum for Colorista II, I had mixed feelings. I’m always happy about shiny new tools that threaten to make my life easier, but to be honest I wasn’t a particular fan of the original Colorista. However, software evolves, and a new version deserves a new look, so I downloaded the demo for Final Cut Pro, and gave it a whirl on a short scene from an old project.
Before I dive into the details of my first look, let me just give you my resulting impressions right up front. I feel that Colorista II is a worthwhile addition to the NLE colorists’s toolkit, and will live alongside the other plugins you’ve been using very nicely. Its ample feature set may even replace some plugins you’ve been using with a better mousetrap.
However, as well-thought out as it is overall, I do find some of the controls to be a bit unwieldy. Also, through no fault of its own, Colorista II is chained to the performance, effects interface, shot comparison mechanisms, and grade management capabilities, not to mention control surface compatibility, of your [...]
Continue reading Taking a Quick Look At Colorista II
A paper look-up-table
I let myself get pulled into responding to a thread at Creative Cow’s DaVinci forum on 3D LUT calibration, but felt that the subject might benefit from a bit more elaboration. I’ve been researching LUT calibration of prosumer display devices in greater detail for a small section of my upcoming book, which I hope will cast some more light on an admittedly arcane subject about which there’s a bit of confusion. However, LUTs are an example of high-end tools and methodologies that are increasingly within the reach of smaller facilities who aren’t afraid of a bit of research, and 3D LUT calibration, once the domain of high-end film facilities, is worth knowing more about if you require color critical monitoring.
To massively oversimplify, a 3D LUT is a three-dimensional look-up-table for taking incoming image data and converting it to another set of image data—in other words it’s a color and contrast transformation. 1D LUTs are suitable for calibrating a monitor’s gamma response, but a 3D LUT is required for changing the gamut, or range of color that a display shows.
LUTs can be used for many [...]
Continue reading An Orbital Overview of Monitor LUT Calibration
I had some back and forth with friend and colleague Patrick Inhofer (Colorist and owner of FINI), about what the “official” peak luma setting should be for a monitor he’s evaluating. The long and short of my response was that SMPTE Recommended Practice document RP 166-1995 (now archived, but there’s no replacement just yet) calls for 35 footlamberts (ft-L) of light output for a calibrated CRT display, which when converted to cd/m2 is 119.92 nits (round up to 120). In other words, a 100 IRE white field, when measured, should be outputting 35 ft-L or 120 nits. This was decided in the CRT days, which are waning, but so far as I know it’s the only official peak luma standard in place for color critical monitoring on a self-illuminated display (the projection standard is 14 ft-L).
However, there are all sorts of posts where folks claim all sorts of peak luma values that they prefer to use for their own monitoring situation. When I’m asked to explain why, it’s always difficult to do so without either taking sides or wondering if one or another emerging monitor technologies really does merit revisiting the previous standard. [...]
Continue reading Monitoring Peak Luma Funnies
Movie poster for The Girl With the Dragon Tattoo
…but 15 years ago it would’ve been.
First off, GWTDT (sorry, I just can’t keep typing the whole title) is an exceptionally crafted thriller and mystery that weaves in thoughtful characterizations and startling glimpses of grotesque horror and awkward sexuality. If you can’t tell from all that, I really liked it. However, I was reflecting this afternoon that the technology used for the digital research that was portrayed throughout, and which was a major motivator of the plot, wasn’t the focus of the story. In fact, the titular character’s skills with the computer were, within the context of the story, almost prosaic despite her clear virtuosity.
This stands in stark contrast to several high-tech thrillers I’ve seen in recent years wherein any portrayal of competent computer use continues to be some kind of hyper-realized graphics and animation extravaganza, with characters pulling off ridiculous hijinks with the wave of a mouse and a few taps of the keyboard. Furthermore, “hackers” and computer experts are usually shown having superhuman analytical skills, with individual characters finding hidden codes and patterns that rooms full [...]
Continue reading “The Girl With the Dragon Tattoo” Is Not a Techno-Thriller
The south hall NAB show floor (where all the postproduction was) on Wednesday was packed.
Upon my return to New York and my first full night’s sleep in a week, I thought it would be good to follow up upon my last post and share some experiences from the rest of the show before they faded from memory. Overall, I had a great time visiting the different vendors of color correction hardware and software and comparing what they can do. Interestingly, the south hall (where most of the postproduction hardware/software vendors were located) was packed, much moreso then what I saw of the north and center halls, where all the production and distribution gear was located. With the abundance of tools now available to enable talented people to do increasingly incredible things, it’s a good time to be involved with post.
I got a fuller demo of the workflow involved with moving Avid and FCP projects to and from Baselight. Baselight has a clean, if packed, user interface, and as far as I can tell has pretty much every software tool ever devised for making [...]
Continue reading Notes From NAB, Part Deux
Another year's pilgrimage to NAB, in Vegas…
Well this year’s NAB is shaping up to be a doozy. Having spent the day chatting with representatives from various vendors of color correction software, color critical broadcast monitors, and accelerated storage systems, all of which I take a professional interest in, I thought I’d share some end of day thoughts.
Of course, the biggest news is Blackmagic/Davinci’s announcement of a $995 Mac OS X compatible, software-only license of their flagship color correction application, Resolve. Spending $30K gets you the overwhelmingly designed control surfaces (USB connected, by the way), while $50K gets you the control surface and a Linux license (and then you need to buy the appropriate CPU/multi-GPU configuration to run it).
A terrible picture of a terrific color correction system, Resolve for Mac OS X
Interestingly, on Mac OS X, you’ll end up installing two NVidia GPUs into your Mac Pro, one in the default slot that’s used to run the UI, and a second one to do the image processing. Coupled with an additional Blackmagic card for video I/O (they say they’ll introduce compatibility with [...]
Continue reading Notes From NAB
I’m a week overdue in mentioning this, but after a month of preparation and two weeks of backbreaking work, I’ve moved my color correction suite to co-locate with Twitch Post, with whom I’m partnering to offer my color correction services to an even more diverse clientele.
For those of you who’ve already been working with me, nothing has changed. You can still reach me through correctionforcolor.com and contact me directly for inquiries and scheduling, and I offer the same range of color correction and compositing services as before. However, being located at Twitch means that additional editorial and finishing services are also available under the same roof, should you need them!
My new, larger suite offers many advantages, not the least of which is a huge 114″ front-projection screen (nearly 10′ diagonal), for an immersive grading theater experience suitable for any project. My HD-native projector is THX-calibrated, and the entire room has been constructed to conform to established digital cinema evaluation standards. Narrative and documentary features, shorts, and promos can be color corrected with complete confidence that what’s on the screen is what the audience will see.
And not only have I moved, but I’ve [...]
Continue reading I’ve Moved! (My Suite)
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You’ve Found Me Congratulations on being intrepid enough to track down my small corner of the web. I'll likely be rattling on about my latest writing project, color correction observations, or production that's underway (which at the moment is my web serial, Starship Detritus). Whatever the topic, you're welcome to browse through and comment—I'm glad to hear from you.
Books and Videos 
Coming this fall. I'm currently working on this platform-agnostic book covering all aspects of professional color correction, in theory and practice. This book pulls together information ranging from room setup, detailed color and contrast theory, practical correction techniques, QC adherence, scene balancing, image ideals, all the way to a wealth of creative techniques—this book has something for colorists at all levels. Available for pre-order from Amazon.com.
On behalf of Ripple Training, I've created a one-hour set of instructional videos covering every new feature in Color 1.5. If you already know Color, and just want to get up to speed with what's new, these will give you a focused tour of the new features and workflows available in this upgrade to Final Cut Studio 3. Best of all, these are available for immediate download in iTunes! New Features in Color 1.5.
I used to write an ongoing series on grading in Color in the digital newsletter Edit Well. Many of my articles from the series, and others from experts in Final Cut Studio applications, have been collected into the verbosely named book Edit Well: Final Cut Studio Techniques from the Pros.
My own book, the Encyclopedia of Color Correction, is a focused compilation of color correction methods and information I've found valuable while working with my own clients. Combining color correction techniques with technical information relevant to colorists and finishing editors alike, it's an invaluable resource to post production pros who are using Final Cut Studio. Available now from Amazon.com.
If you're a fan of video tutorials, I recorded a series of 13 video lessons that provides over four hours of training spanning every room in Color. Buy it now from Magnet Media.
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