Did you pick the right camera? Part 2

HDR (high dynamic range) imagery and higher display resolutions start with the camera. Unfortunately that’s also where the misinformation starts. That’s because the terminology is based on displays and not on camera sensors and lenses.

Resolution

4K is pretty common, 8K products are here, and 16K may be around the corner. Resolution is commonly expressed as the horizontal dimension, but in fact, actual visual resolution is intended to be measured vertically. A resolution chart uses converging lines. The point at which you can no longer discern between the lines is the limit of the measurable resolution. That isn’t necessarily a pixel count.

The second point to mention is that camera sensors are built with photosites that only loosely equate to pixels. The hitch is that there is no 1:1 correlation between a sensor’s photosites and display pixels on a screen. This is made even more complicated by the design of a Bayer-pattern sensor that is used in most professional video cameras. In addition, not all 4K cameras look good when you analyze the image at 100%. For example, nearly all early and/or cheap drone and ‘action’ cameras appear substandard when you actually look at the image closely. The reasons include cheap plastic lenses and high compression levels.

The bottom line is that when a company like Netflix won’t accept an ARRI Alexa as a valid 4K camera for its original content guidelines – in spite of the number of blockbuster feature films captured using Alexas – you have to take it with a grain of salt. Ironically, if you shoot with an Alexa in its 4:3 mode (2880 x 2160) using anamorphic lenses (2:1 aspect squeeze), the expanded image results in a 5760 x 2160 (6K) frame. Trust me, this image looks great on a 4K display with plenty of room to crop left and right. Or, a great ‘scope image. Yes, there are anamorphic lens artifacts, but that’s part of the charm as to why creatives love to shoot that way in the first place.

Resolution is largely a non-issue for most camera owners these days. There are tons of 4K options and the only decision you need to make when shooting and editing is whether to record at 3840 or 4096 wide when working in a 4K mode.

Log, raw, and color correction

HDR is the ‘next big thing’ after resolution. Nearly every modern professional camera can shoot footage that can easily be graded into HDR imagery. That’s by recording the image as either camera raw or with a log color profile. This lets a colorist stretch the highlight information up to the peak luminance levels that HDR displays are capable of. Remember that HDR video is completely different from HDR photography, which can often be translated into very hyper-real photos. Of course, HDR will continue to be a moving target until one of the various competing standards gains sufficient traction in the consumer market.

It’s important to keep in mind that neither raw nor log is a panacea for all image issues. Both are ways to record the linear dynamic range that the camera ‘sees’ into a video colorspace. Log does this by applying a logarithmic curve to the video, which can then be selectively expanded again in post. Raw preserves the sensor data in the recording and pushes the transformation of that data to RGB video outside of the camera. Using either method, it is still possible to capture unrecoverable highlights in your recorded image. Or in some cases the highlights aren’t digitally clipped, but rather that there’s just no information in them other than bright whiteness. There is no substitute for proper lighting, exposure control, and shaping the image aesthetically through creative lighting design. In fact, if you carefully control the image, such as in a studio interview or a dramatic studio production, there’s no real reason to shoot log instead of Rec 709. Both are valid options.

I’ve graded camera raw (RED, Phantom, DJI) and log footage (Alexa, Canon, Panasonic, Sony) and it is my opinion that there isn’t that much magic to camera raw. Yes, you can have good iso/temp/tint latitude, but really not a lot more than with a log profile. In one, the sensor de-Bayering is done in post and in the other, it’s done in-camera. But if a shot was recorded underexposed, the raw image is still going to get noisy as you lift the iso and/or exposure settings. There’s no free lunch and I still stick to the mantra that you should ‘expose to the right’ during production. It’s easier to make a shot darker and get a nice image than going in the other direction.

Since NAB 2018, more camera raw options have hit the market with Apple’s ProRes RAW and Blackmagic RAW. While camera raw may not provide any new, magic capabilities, it does allow the camera manufacturer to record a less-compressed file at a lower data rate.  However, neither of these new codecs will have much impact on post workflows until there’s a critical mass of production users, since these are camera recording codecs and not mezzanine or mastering codecs. At the moment, only Final Cut Pro X properly handles ProRes RAW, yet there are no actual camera raw controls for it as you would find with RED camera raw settings. So in that case, there’s actually little benefit to raw over log, except for file size.

One popular raw codec has been Cinema DNG, which is recorded as an image sequence rather than a single movie file. Blackmagic Design cameras had used that until replaced by Blackmagic RAW.  Some drone cameras also use it. While I personally hate the workflow of dealing with image sequence files, there is one interesting aspect of cDNG. Because the format was originally developed by Adobe, processing is handled nicely by the Adobe Camera Raw module, which is designed for camera raw photographs. I’ve found that if you bring a cDNG sequence into After Effects (which uses the ACR module) as opposed to Resolve, you can actually dig more highlight detail out of the images in After Effects than in Resolve. Or at least with far less effort. Unfortunately, you are stuck making that setting decision on the first frame, as you import the sequence into After Effects.

The bottom line is that there is no way to make an educated decision about cameras without actually testing the images, the profile options, and the codecs with real-world footage. These have to be viewed on high quality displays at their native resolutions. Only then will you get an accurate reading of what that camera is capable of. The good news is that there are many excellent options on the market at various price points, so it’s hard to go wrong with any of the major brand name cameras.

Click here for Part 1.

Click here for Part 3.

©2019 Oliver Peters

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Did you pick the right camera? Part 1

There are tons of great cameras and lenses on the market. While I am not a camera operator, I have been a videographer on some shoots in the past. Relevant production and camera logistical issues are not foreign to me. However, my main concern in evaluating cameras is how they impact me in post – workflow, editing, and color correction. First – biases on the table. Let me say from the start that I have had the good fortune to work on many productions shot with ARRI Alexas and that is my favorite camera system in regards to the three concerns offered in the introductory post. I love the image, adopting ProRes for recording was a brilliant move, and the workflow couldn’t be easier. But I also recognize that ARRI makes an expensive albeit robust product. It’s not for everyone. Let’s explore.

More camera choices – more considerations

If you are going to only shoot with a single camera system, then that simplifies the equation. As an editor, I long for the days when directors would only shoot single-camera. Productions were more organized and there was less footage to wade through. And most of that footage was useful – not cutting room fodder. But cameras have become cheaper and production timetables condensed, so I get it that having more than one angle for every recording can make up for this. What you will often see is one expensive ‘hero’ camera as the A-camera for a shoot and then cheaper/lighter/smaller cameras as the B and C-cameras. That can work, but the success comes down to the ingredients that the chef puts into the stew. Some cameras go well together and others don’t. That’s because all cameras use different color science.

Lenses are often forgotten in this discussion. If the various cameras being used don’t have a matched set of lenses, the images from even the exact same model cameras – set to the same settings – will not match perfectly. That’s because lenses have coloration to them, which will affect the recorded image. This is even more extreme with re-housed vintage glass. As we move into the era of HDR, it should be noted that various lens specialists are warning that images made with vintage glass – and which look great in SDR – might not deliver predictable results when that same recording is graded for HDR.

Find the right pairing

If you want the best match, use identical camera models and matched glass. But, that’s not practical or affordable for every company nor every production. The next best thing is to stay within the same brand. For example, Canon is a favorite among documentary producers. Projects using cameras from the EOS Cinema line (C300, C300 MkII, C500, C700) will end up with looks that match better in post between cameras. Generally the same holds true for Sony or Panasonic.

It’s when you start going between brands that matching looks becomes harder, because each manufacturer uses their own ‘secret sauce’ for color science. I’m currently color grading travelogue episodes recorded in Cuba with a mix of cameras. A and B-cameras were ARRI Alexa Minis, while the C and D-cameras were Panasonic EVA1s. Additionally Panasonic GH5, Sony A7SII, and various drones cameras were also used. Panasonic appears to use a similar color science as ARRI, although their log color space is not as aggressive (flat). With all cameras set to shoot with a log profile and the appropriate REC709 LUT applied to each in post (LogC and Vlog respectively) I was able to get a decent match between the ARRI and Panasonic cameras, including the GH5. Not so close with the Sony or drone cameras, however.

Likewise, I’ve graded a lot of Canon C300 MkII/C500 footage and it looks great. However, trying to match Canon to ARRI shots just doesn’t come out right. There is too much difference in how blues are rendered.

The hardest matches are when professional production cameras are married with prosumer DSLRs, such as a Sony FS5 and a Fujifilm camera. Not even close. And smartphone cameras – yikes! But as I said above, the GH5 does seem to provide passible results when used with other Panasonic cameras and in our case, the ARRIs. However, my experience there is limited, so I wouldn’t guarantee that in every case.

Unfortunately, there’s no way to really know when different brands will or won’t create a compatible A/B-camera combination until you start a production. Or rather, when you start color correcting the final. Then it’s too late. If you have the luxury of renting or borrowing cameras and doing a test first, that’s the best course of action. But as always, try to get the best you can afford. It may be better to get a more advanced camera, but only one. Then restructure your production to work with a single-camera methodology. At least then, all of your footage should be consistent.

Click here for the Introduction.

Click here for Part 2.

©2019 Oliver Peters

Did you pick the right camera? Intro

My first facility job after college at a hybrid production/post company included more than just editing. Our largest production effort was to produce, post, and dub weekly price-and-item retail TV commercials for a large, regional grocery chain. This included two to three days a week of studio production for product photography (product displays, as well as prepared food shots).

Early on, part of my shift included being the video shader for the studio camera being used. The video shader in a TV station operation is the engineering operator who makes sure the cameras are set up and adjusts video levels during the actual production. However, in our operation (as would be the case in any teleproduction facility of that time) this was a more creative role – more akin to a modern DIT (digital imaging technician) than a video engineer. It didn’t involve simply adjusting levels, but also ‘painting’ the image to get the best-looking product shots on screen. Under the direction of the agency producer and our lighting DP/camera operator, I would use both the RGB color balance controls of the camera, along with a built-in 6-way secondary color correction circuit, to make each shot look as stylistic – and the food as appetizing – as possible. Then I rolled tape and recorded the shot.

This was the mid-1970s when RCA dominated the broadcast camera market. Production and gear options where either NTSC, PAL, or film. We owned an RCA TK-45 studio camera and a TKP-45 ‘portable’ camera that was tethered to a motor home/mobile unit. This early RCA color correction system of RGB balance/level controls for lift/gamma/gain ranges, coupled with a 6-way secondary color correction circuit (sat/hue trim pots for RGBCMY) was used in RCA cameras and telecines. It became the basis for nearly all post-production color correction technology to follow. I still apply  those early fundamentals that I learned back then in my work today as a colorist.

Options = Complexity

In the intervening decades, the sheer number of camera vendors has blossomed and surpassed RCA, Philips, and the other few companies of the 1970s. Naturally, we are well past the simple concerns of NTSC or PAL; and film-based production is an oddity, not the norm. This has introduced a number of challenges:

1. More and cheaper options mean that productions using multiple cameras is a given.

2. Camera raw and log recording, along with modern color correction methods, give you seemingly infinite possibilities – often making it even harder to dial in the right look.

3. There is no agreement of file format/container standards, so file-based recording adds workflow complexity that never existed in the past.

In the next three blog posts, I will explore each of these items in greater depth.

©2019 Oliver Peters

Hawaiki AutoGrade

The color correction tools in Final Cut Pro X are nice. Adobe’s Lumetri controls make grading intuitive. But sometimes you just want to click a few buttons and be happy with the results. That’s where AutoGrade from Hawaiki comes in. AutoGrade is a full-featured color correction plug-in that runs within Final Cut Pro X, Motion, Premiere Pro and After Effects. It is available from FxFactory and installs through the FxFactory plug-in manager.

As the name implies, AutoGrade is an automatic color correction tool designed to simplify and speed-up color correction. When you install AutoGrade, you get two plug-ins: AutoGrade and AutoGrade One. The latter is a simple, one-button version, based on global white balance. Simply use the color-picker (eye dropper) and sample an area that should be white. Select enable and the overall color balance is corrected. You can then tweak further, by boosting the correction, adjusting the RGB balance sliders, and/or fine-tuning luma level and saturation. Nearly all parameters are keyframeable, and looks can be saved as presets.

AutoGrade One is just a starter, though, for simple fixes. The real fun is with the full version of AutoGrade, which is a more comprehensive color correction tool. Its interface is divided into three main sections: Auto Balance, Quick Fix, and Fine-Tune. Instead of a single global balance tool, the Auto Balance section permits global, as well as, any combination of white, black, and/or skin correction. Simply turn on one or more desired parameters, sample the appropriate color(s) and enable Auto Balance. This tool will also raise or lower luma levels for the selected tonal range.

Sometimes you might have to repeat the process if you don’t like the first results. For example, when you sample the skin on someone’s face, sampling rosy cheeks will yield different results than if you sample the yellowish highlights on a forehead. To try again, just uncheck Auto Balance, sample a different area, and then enable Auto Balance again. In addition to an amount slider for each correction range, you can also adjust the RGB balance for each. Skin tones may be balanced towards warm or neutral, and the entire image can be legalized, which clamps video levels to 0-100.

Quick Fix is a set of supplied presets that work independently of the color balance controls. These include some standards, like cooling down or warming up the image, the orange and teal look, adding an s-curve, and so on. They are applied at 100% and to my eye felt a bit harsh at this default. To tone down the effect, simply adjust the amount slider downwards to get less intensity from the effect.

Fine-Tune rounds it out when you need to take a deeper dive. This section is built as a full-blown, 3-way color corrector. Each range includes a luma and three color offset controls. Instead of wheels, these controls are sliders, but the results are the same as with wheels. In addition, you can adjust exposure, saturation, vibrance, temperature/tint, and even two different contrast controls. One innovation is a log expander, designed to make it easy to correct log-encoded camera footage, in the absence of a specific log-to-Rec709 camera LUT.

Naturally, any plug-in could always offer more, so I have a minor wish list. I would love to see five additional features: film grain, vignette, sharpening, blurring/soft focus, and a highlights-only expander. There are certainly other individual filters that cover these needs, but having it all within a single plug-in would make sense. This would round out AutoGrade as a complete, creative grading module, servicing user needs beyond just color correction looks.

AutoGrade is a deceptively powerful color corrector, hidden under a simple interface. User-created looks can be saved as presets, so you can quickly apply complex settings to similar shots and set-ups. There are already many color correction tools on the market, including Hawaiki’s own Hawaiki Color. The price is very attractive, so AutoGrade is a superb tool to have in your kit. It’s a fast way to color-grade that’s ideal for both users who are new or experienced when it comes to color correction.

(Click any image to see an enlarged view.)

©2018 Oliver Peters

FCPX Color Wheels Take 2

Prior to version 10.4, the color correction tools within Final Cut Pro X were very basic. You could get a lot of work done with the color board, but it just didn’t offer tools competitive with other NLEs – not to mention color plug-ins or a dedicated grading app like DaVinci Resolve. With the release of 10.4, Apple upped the game by adding color wheels and a very nice curves implementation. However, for those of us who have been doing color correction for some time, it quickly became apparent that something wasn’t quite right in the math or color science behind these new FCPX color wheels. I described those anomalies in this January post.

To summarize that post, the color wheels tool seems to have been designed according to the lift/gamma/gain (LGG) correction model. The standard behavior for LGG is evident with a black-to-white gradient image. On a waveform display, this appears as a diagonal line from 0 to 100. If you adjust the highlight control (gain), the line appears to be pinned at the bottom with the higher end pivoting up or down as you shift the slider. Likewise, the shadow control (lift) leaves the line pinned at the top with the bottom half pivoting. The midrange control (gamma) bends the middle section of the line inward or outward, with no affect on the two ends, which stay pinned at 0 and 100, respectively. In addition to luminance value, when you shift the hue offset to an extreme edge – like moving the midrange puck completely to yellow – you should still see some remaining black and white at the two ends of the gradient.

That’s how LGG is supposed to work. In FCPX version 10.4, each color wheel control also altered the levels of everything else. When you adjusted midrange, it also elevated the shadow and highlight ranges. In the hue offset example, shifting the midrange control to full-on yellow tinted the entire image to yellow, leaving no hint of black or white. As a result, the color wheels correction tool was unpredictable and difficult to use, unless you were doing only very minor adjustments. You ended up chasing your tail, because when one correction was made, you’d have to go back and re-adjust one of the other wheels to compensate for the unwanted changes made by the first adjustment.

With the release of FCPX 10.4.1 this April, Apple engineers have changed the way the color wheels tool behaves. Corrections now correspond to the behavior that everyone accepts as standard LGG functionality. In other words, the controls mostly only affect their part of the image without also adjusting all other levels. This means that the shadows (lift) control adjusts the bottom, highlights (gain) will adjust the top end, and midrange (gamma) will lighten or darken the middle portion of the image. Likewise, hue offsets don’t completely contaminate the entire image.

One important thing to note is that existing FCPX Libraries created or promoted under 10.4 will now be promoted again when opened in 10.4.1. In order that your color wheel corrections don’t change to something unexpected when promoted, Projects in these Libraries will behave according to the previous FCPX 10.4 color model. This means that the look of clips where color wheels were used – and their color wheel values – haven’t changed. More importantly, the behavior of the wheels when inside those Libraries will also be according to the “old” way, should you make any further corrections. The new color wheels behavior will only begin within new Libraries created under 10.4.1.

These images clarify how the 10.4.1 adjustments now work (click to see enlarged and expanded views).

©2018 Oliver Peters

Blackmagic Design DaVinci Resolve 14

DaVinci Resolve has made its mark as one of the premier color correction applications for the film and video industries. With the introduction of Resolve 14*, it’s clear that Blackmagic Design has set its sights higher. Advanced editing functions and the inclusion of the Fairlight audio engine put Resolve on track to be the industry’s latest all-in-one post-production powerhouse. I’ve reviewed Resolve in the past as a grading application, but my focus here is editing. Right at the start, let me paraphrase the judges on History Channel’s Forged in Fire series – ‘This NLE can cut!’ If you have no prior allegiances to other editing platforms, then using Resolve as your NLE of choice is a no-brainer.

(*This review was originally written right after the release of Resolve 14 in late 2017.)

DaVinci Resolve 14 comes in two flavors, DaVinci Resolve 14 (free) and DaVinci Resolve Studio ($299). Upgrades have been free to date. It’s the only NLE to support three operating systems: macOS, Windows, and Linux. Mac users also have the option to download Resolve (free) or purchase Resolve Studio through the Apple Mac App Store. These versions are basically the same as those on Blackmagic Design’s website, but with some differences, due to the requirement that App Store software be sandboxed.

Resolve offers the majority of the same features as Resolve Studio. The primary limitations are that exports are capped at UltraHD (3840×2160), and that features such as stereo3D, lens distortion correction, noise reduction, and collaboration require Resolve Studio. Regardless of the version, Resolve is a very deep application that’s been battle-tested through years of high-pressure, enterprise-grade deployment. But is that enough to sway loyal Final Cut Pro X, Premiere Pro, or Media Composer editors to switch? There’s certainly interest, as Stephen Mirrione pointed out in my recent Suburbicon interview, so I wouldn’t be surprised to hear news of a TV show or small feature film being edited with Resolve in the coming year.

The all-in-one concept

Creating a single application that’s good at many different tasks can be daunting and more often than not has been unsuccessful. In the case of Resolve, Blackmagic Design has taken a modal approach by splitting the interface into five pages: Media (ingest/import), Edit, Color, Fairlight (audio mixing), and Deliver (export/output).

The workflow follows a logical, left-to-right path through these five stages of post-production. With each page/mode change, the user interface is reconfigured to best suit the task at hand. The Edit page sports a standard source/record/bin/track layout similar to Media Composer, Premiere Pro, or Final Cut Pro 7. Color switches to the familiar tools and nodes of DaVinci color correction. The Fairlight mixing page isn’t just a mimic of the Fairlight interface. The engineers completely swapped out the audio guts of Resolve and replaced it with the Fairlight audio engine.

Not only is the interface that of a respected DAW, but it is also possible to expand your system with Fairlight’s audio acceleration card, as well as add a Fairlight mixing desk. This means that in a multi-suite facility, you can have task-specific rooms optimized for editing, color grading, or audio mixing – all using the exact same software application without the need for roundtrips or other list translations.

But does it work?

I put both versions of Resolve 14 through the paces and the application is reasonably solid, given how much has changed from version 12 (there was no version 13). General media management, editing, and audio processing is top notch. If you want audio/video output, Blackmagic Design Decklink or UltraStudio hardware is required. There is also a Cinema viewer function for fullscreen viewing on your computer display. With dual displays, the edit interface can be on one along with fullscreen video on the other.

The Fairlight mode will likely require a bit of rethinking by editors used to mixing audio in other NLEs, since it uses a DAW-style interface. Many well-known physical mixing consoles, like those from Solid State Logic, feature channel strips with built-in EQs, compressors, etc. That’s how Fairlight treats these software channels or tracks. Each track can have its own combination of Fairlight audio processing functions. Stick with those and you’ll be happy, although other audio filters on your computer, like Apple AU plug-ins, are accessible. Mixing and audio editing is good with subframe accuracy and the 14.1 update added linked groups to lock faders together. The pace of Fairlight integration was quite fast, but it’s still a bit rough. I encountered a number of application crashes only in the Fairlight page, while scrubbing audio.

Whether or not you like the editing is more a function of personal style and preference. The user interface design is a lot like Final Cut Pro X, except with bins and tracks. Interface windows, tabs, and panels can be opened or pulled down into various screen configurations, but you don’t have freeform control over size and position. Clearly Premiere Pro is king in that department. Some design choices aren’t consistent. For example, you can’t enable a single-viewer layout when using two displays.

Multicam editing is solid, but I experienced a small bit of latency in the viewer when cutting camera angles on-the-fly. It’s minor and may or may not bother you. You can sync clips by various methods, such as timecode or waveform, but oddly, it seemed to be too lax. In my tests, it would frequently sync clips that it shouldn’t have when a sync relationship didn’t exist.

There are a number of things in Resolve’s design that take getting used to. For example, a Resolve project is locked to the frame rate you picked when that new project was created – same as with Avid. This means you can’t mix sequences with different frame rates within the same project. There are no adjustment layers, although you can fake it in the Color page by using clip and program-based corrections. Color management via LUTs (look-up tables) is much deeper than any other NLE. You can set color management with LUTs to be global, which is best when the project uses only one camera type. Conversely, input LUTs may be applied singly or in a batch to specific cameras in a bin. But, when you do that, the LUT process doesn’t show up in the color correction node (only its result), when you switch to the Color page. On the plus side, real time performance has been improved from previous versions and the built-in effects include filters that you don’t often find in the basic build of other NLEs, like glow and watercolor effects. In addition to great built-in effects, third-party OpenFX packages, like Boris Continuum Complete and Sapphire are also available.

Collaboration

Resolve uses bin-locking like Avid Media Composer. The first editor to open a bin has read/write permission to it. Any other editor can open that same bin in a read-only mode. For example, in a long-form project, separate bins might be organized for Act 1, Act 2, and so on. Different editors can separately work on parts of the film at the same time. Since this all happens in a single database file, it always reflects the most current state of the project.

To set up shared projects, a different PostgreSQL database is required, which is installed through the custom options of the installer. Make sure you are using the most recent version when upgrading Resolve, since the older versions of PostgreSQL are no longer compatible with the newest OS versions. One machine on the network hosts this database and then other workstations connect to that database to access the Resolve projects. Only that host machine needs to have PostgreSQL software installed on it. The process of adding and connecting shared databases has been improved and simplified with the release of 14.1.1 (and later), which now includes an additional server set-up utility application.

In testing collaboration features, I initially ran into set-up problems. These were eventually fixed when I disabled the macOS firewall on the host machine, which was blocking access from the other connected Macs to its shared database. This took some back and forth with Blackmagic Design’s helpful support engineers until we figured out why I was getting the connection errors. Since I had to return the additional “dongle” (USB license key) before this was fixed, I wasn’t able to test two editors simultaneously editing within the same open project. However, the ability to open any shared project from any qualified computer on the network was just fine.

DaVinci Resolve Micro Panel

I also tested the smaller, bus-powered DaVinci Resolve Micro panel. The Micro panel is just the right size for an editor or a DIT on set. It’s smaller than the Mini (tested previously in another review), because it doesn’t have the upward slanting portion in the back; therefore, it’s a better physical fit between your computer keyboard and display. You don’t have to shuffle desk real estate between tools, as you do with the Micro panel. In spite of not having the extra controls and LCD displays of the Mini, the Micro panel combines most of the control functions you need for fast grading. If you are an editor who is heavy into color correction, then this is a must-have for Resolve.

I took an instant liking to the Micro. You can use both hands to quickly and intuitively work the trackballs and knob controls, making for faster and better correction. It’s tactile, with next and previous clip buttons to quickly advance through the timeline, so you can keep your eyes on the screen. I grade in Resolve, Avid, Premiere Pro, and Final Cut Pro X, and all of that is with a mouse. Using the panel easily resulted in faster grading by a factor at least 3X or 4X. I also achieved better-looking corrections with fewer steps or processes than grading in any of these other applications.

Conclusion

Overall, there’s a lot to love about Resolve, in spite of a few rough edges. In general, it seems more stable under macOS Sierra than with High Sierra. If you use Resolve on a Mac, then you are stuck dealing with Apple’s platform changes. For example, recent Macs that use an Nvidia GPU are at a disadvantage under High Sierra, because Nvidia is just now developing drivers for CUDA under this OS. I experienced a number of crashes running Resolve 14 on my 2014 MacBook Pro until I manually changed the Resolve hardware configuration under Resolve’s preferences from CUDA to using Metal. When I installed what was supposed to be the newest CUDA driver, I still received a prompt that no CUDA-compliant card was present. But, it’s working fine using Metal. Macs with AMD GPUs should be fine.

Resolve 14 is a dense tool, with a lot of depth in various menus, which some may find daunting. This review would be a lot longer if I went even deeper into the many specific features of this application. Yet, it is easy for new users to hit the ground running and then learn as they go. For many, this is their mythical “Final Cut Pro 8”. In any case, DaVinci Resolve 14 is the best incarnation of the all-in-one concept to date. If you add Blackmagic Design’s Fusion visual effects software into the mix (also available in free and paid versions), the result is a combination that’s tough to beat at any price.

Blackmagic Design’s engineers have shown impressive development over a very short period of time, so I fully expect Blackmagic to give the three “A” companies a run for their money. Even if you use another tool as your main editing application, Resolve is a great addition to the toolbox. Using it becomes addictive. Give it a try and you might just find it becomes your first choice.

©2017, 2018 Oliver Peters

What’s up with Final Cut’s Color Wheels?

NOTE: The information presented here has been superseded by the release of FCPX 10.4.1 in April 2018. With that release the color wheels model has been changed. Please read the linked blog post for updated information.

Apple Final Cut Pro X 10.4 introduced new, advanced color correction tools to this editing application, including color wheels, curves, and hue vs. saturation curves. These are tools that users of other NLEs have enjoyed for some time – and, which were part of Final Cut Studio (FCP 7, Color). Like others, my first reaction was, “Super! They’ve added some nice advanced tools, which will improve the use of FCPX for higher-end users.” But, as I started to primarily use the Color Wheels with real correction work, I quickly realized that something wasn’t quite right in how they operated. Or at least, they didn’t work in a way that we’ve come to understand.

In trying to figure it out, I reached out to other industry pros and developers for their thoughts. Naturally this led to some spirited discussions at forums like those at Creative COW. However, other editors have noticed the same problems, so you can also find threads in the Facebook FCPX group and at FCP.co. It is certainly easy to characterize this as just another internet kerfuffle, surrounding Apple’s “think different” approaches to FCPX. But those arguments fall flat when you actually try to use the tools as intended.

The FCPX Color Wheels panel includes four wheels – Master, Shadows, Midtones, and Highlights. The puck in the center of each wheel is a hue offset control to push hues in the direction that you move the puck. The slider to the right of the wheel controls the brightness of that range. The left slider controls the saturation. One of the main issues is that when you adjust luminance using one of these controls, the affected range is too broad. Specifically, in the case of the Midtones control, as you adjust the luminance slider up or down, you are affecting most of the image and not just the midrange levels. This is not the way this type of control normally works in other tools, and in fact, it’s not how FCPX’s Color Board controls work either.

“What’s the big deal?” you might ask. Fair enough. I see two operational issues. The first is that to properly grade the image using the Color Wheels, you end up having to go back-and-forth a lot between wheels, to counteract the changes made by one control with another. The second is that using the Midtones slider tends to drive highlights above 100 IRE, where they will be clipped if any broadcast limiting is used. This doesn’t happen with other color tools, notably Apple’s own Color Board.

A lot of the discussion focuses on luma levels and specifically the Midtones slider, since it’s easy to see the issue there. However, other controls are also affected, but that’s too much to dissect in a single post. Throughout this post, be sure to click on the images to see the full view. I have presented various samples against each other and you will only get the full understanding if you open the thumbnail (which is small but also cropped) to the full image. I have compared the effect using five different tools – the Color Board, the Color Wheels, a color corrector plug-in that I built as a Motion template using Motion effects, Rubber Monkey Software FilmConvert (the wheels portion only), and finally, the Adobe Lumetri controls in Premiere Pro.

I am using three different test images – a black-to-white ramp, a test pattern, and a demo video image. The ramp without correction will appear as a diagonal line (0-100 IRE) on the scope, which makes it easy to analyze what’s happening. The video image has definite shadow and highlight areas, which lets us see how these controls work in the real world. For example, if you want to brighten the area of the shot where the man is in the shadows, but don’t want to make the highlights any brighter, this would normally be done using a Midtones control. Be aware that these various tools certainly aren’t calibrated the same way and some have a greater range of control than others. The weakest of these is FilmConvert’s wheels, since this plug-in has additional level controls in other parts of its interface.

Color science models

In the various forum threads, the argument is made that Apple is simply using a different color science method or a different weighing of some existing models. That’s certainly possible, since not all color correctors are built the same way. The most common approaches are Lift/Gamma/Gain and Shadows/Mids/Highlights. Be careful with naming. Just because something uses the terminology of Shadows, Midtones, and Highlights, does not mean that it also uses the SMH color science model. Many tools use the Lift/Gamma/Gain model, but in fact, call the controls shadows (Lift), mids (Gamma), and highlights (Gain). Another term you may run across is Set-up in some correction tools. This is typically used for control of shadows (equal to Lift), but can also function is an offset control that raises the level of the entire image. Avid Symphony employs this solution. Finally, both Symphony and Adobe SpeedGrade use what has been dubbed a 12-way color corrector. Each range is further subdivided into its own subset of shadows, mids, and highlights controls.

An LGG model provides broad control of shadows and highlights, with the midtones control working like a curve that covers the whole range, but with the largest effect in the middle. An SMH model normally divides the levels into three distinct, precisely overlapping ranges. This is much like a three-band audio equalizing filter. A number of the color correctors add a luma range control, which gives the user the ability to change how much of the image a specific range will affect. In other words, how broad is the control of the shadows, mids, or highlights control? This is like a Q control in an audio equalizer, where you change the shape of the envelope at a certain frequency.

Red Giant’s Magic Bullet Looks offers both color correction models with two different tools – the 4-way color corrector (SMH) and the Colorista color corrector (LGG). When you adjust the midrange control of their 4-way, the result is a graceful S-shaped curve to the levels on the waveform.

To study the effect of an LGG-based corrector, test the ramp. The shadows control (Lift) will raise or lower the dark areas of the image without changing the absolute highlights. The diagonal line of the ramp on the waveform essentially pivots, hinged at the 100 IRE point. Conversely, change the highlights control (Gain) pivots the line pinned to 0 IRE (at black). When you adjust the midtones control (Gamma), you create a curve to the line, which stays pinned at 0 and 100 IRE at either end. In this way you are effectively “expanding” or “compressing” the levels in the middle portion of your image without changing the position of your black or white points.

How the various color correction tools react

Looking at the luma control for the Midtones, two things are clear. First, all of these tools are using the LGG color science model. It’s not clear what the Color Wheels are using, but it isn’t SMH, as there is no bulge or S-curve visible in the scope. Second, the Color Wheels quickly drive the image levels into clipping, while the other tools generally keep black and while levels in place. In essence, the Midtones control affects the image more like a master or offset control would, than a typical mids or Gamma control. Yet, clearly Apple’s Color Board controls adhere to the standard LGG model. The concern, of course, is clipping. In the test image of the man walking on the village street, the sunlit building walls on the opposite side of the street will become overexposed and risk being clipped when the Color Wheels are used.

What about color? As a simple test, I next shifted the Midtones puck to the yellow. Bear in mind that the range of each of these controls is different, so you will see varying degrees of yellow intensity. Nevertheless, the way the control should work is that some pure black and white should be preserved at the top and bottom of the video levels. All of these tools maintain that, except for the Color Wheels. There, the entire image is yellow, effectively making the hue offset puck function more like a tint control.

One other issue to note, is that the Color Wheels offer an extraordinarily control range. The hue offset control RGB intensity values go from 0 (center of the wheel) to 1023. However, the puck icon can only go to the rim of the wheel, which it hits at about 200. With a mouse (or numerical entry), you can keep going well past the stop of the wheel icon – five times farther, in fact. The image not only becomes very yellow in this case, but you can easily lose the location of your control, since the GUI position in no longer relevant.

The working theory

The big question is why don’t the Color Wheels conform to established principles, when in fact, the Color Board controls do? Until there is some further clarification from Apple, one possible explanation is with HDR. FCPX 10.4 introduced High Dynamic Range (HDR) features. One of the various HDR standards is Rec. 2020 PQ. In that color space, the 0-100 IRE limitations of Rec. 709 are expanded to 0-10,000 nits. 0-100 nits is roughly the same brightness as we are used to with Rec. 709.

Looking at this image of the man walking along the street – where I’ve attempted to get a pleasing look with all of the tools – you’ll see that the Color Wheels in Rec. 709 don’t react correctly and will drive the highlights into a range to be clipped. However, in the bottom pane, which is the same image in Rec. 2020 PQ color space, the grade looks pretty normal. And, in practice, the Color Wheels controls work more or less the way I would have expected them to work. Yes, the same controls work differently in the different color spaces – properly in 2020 PQ and not in 709.

But why is that the case? I have no answer, but I do have a wild guess. Maybe, just maybe, the Color Wheels were designed for – or intended to only be used for – HDR work. Or maybe there’s conversion or recalibration of the controls that hasn’t taken place yet in this version. If the tool is only calibrated for HDR, then its range and weighing will be completely wrong for Rec. 709 video. If you increase the Midtones luma of the ramp in both Rec. 709 and Rec. 2020 PQ, you’ll see a similar curve. In fact, if you overlay a screen shot of each waveform, placing the full Rec. 709 scope image over the bottom portion of the Rec. 2020 PQ scale, you’ll notice that these sort of align up to about 100 IRE and nits. It’s as if one is simply a slice out of the other.

Regardless of why, this is something where I would hope Apple will provide a white paper or other demonstration of what the best practices will be for using this tool effectively. If it isn’t intentional, and actually is a mistake, then I presume a fix will be forthcoming. In either case, put in your feedback comments to Apple.

A word about HDR

Over the course of testing this tool and this theory, I’ve done a bit of testing with the HDR color spaces in FCPX. If you want to know more about HDR, I would encourage you to check out these contrary blog posts by Stu Maschwitz and Alexis Van Hurkman. I tend to side with Stu’s point-of-view and am not a big fan of HDR.

The way Apple has implemented these features in Final Cut Pro X 10.4 is to allow the user to set and override color spaces. If you set up your project to be Rec. 2020 PQ (and set preferences to “show HDR as raw values”), then the viewer and a/v output (direct from the Mac, not through a hardware i/o device) are effectively dimmed through the Mac’s color profile system. When you grade the image based on the 0-10,000 nits scale, you’ll end up seeing an image that looks pleasing and essentially the same as if you were working in Rec. 709. However – and I cannot over-emphasize this – you are not going to be able to produce an image that’s truly compatible with Dolby Vision and actually look correct as HDR, unless you have the correct AJA i/o hardware and a proper display. And by display, I mean a top-end Dolby, Canon, or Sony unit, costing tens of thousands of dollars.

As I understand the PQ specs, the bulk of the higher range is for the highlights that are normally constrained or clipped in our current video systems. However, that 10,000 nits scale is weighed, so that about 50% of the image value is in the first 100 nits, making it of comparable brightness to the current 100 IRE. The rest of that range is for brighter information, like specular highlights. You don’t necessarily get more brightness in the shadow detail. Therefore, if you are grading a shot in FCPX in a 2020 PQ color space and you only have the computer display to go by, you’ll grade by eye as much as by scope. This means that to get a pleasing image, you will end up making the average appearance of the image brighter than it really should be. When this is viewed on a real HDR monitor, it will be painfully bright. Having a higher-nits computer display, like on the iMac Pro (up to 500 nits), won’t make much difference, unless maybe, you crank the display brightness to its maximum (ouch!).  “Mine goes the 11!”

Right now, HDR is the wild, wild west. If you are smart, you’ll realize that you don’t know what you don’t know. While it’s nice to have these new features in FCPX, they can be very dangerous in the wrong hands.

But that’s another matter. Right now, I just hope Apple (or one of the usual suspects, like Ripple Training, LumaForge, or Larry Jordan) will come out with more elaboration on the Color Wheels.

©2018 Oliver Peters