CineMatch from FilmConvert

One of the many color correction challenges is matching dissimilar cameras used within the same production. This tends to be the case in many web, streaming, and non-scripted projects, where budgets and availability often dictate the mix of cameras to be used. I frequently end up with RED, ARRI, Panasonic, Sony, DJI, and GoPro cameras all in the same show. Most NLEs do include basic, albeit imperfect, shot-matching features. However, now several software developers are taking that challenge head on.

One such developer is New Zealand’s FilmConvert, developers of the FilmConvert Nitrate film emulation plug-in. Their newest product is CineMatch, a camera-matching plug-in that’s currently available for DaVinci Resolve and Premiere Pro – and coming to Final Cut Pro X in the future. As with Nitrate, CineMatch is a cross-platform plug-in that may be purchased for a specific NLE host or as a bundle license to cover all products.

The CineMatch concept is very straightforward. Most productions have a main or “hero” camera – typically designated as the A-camera. Then there are other cameras for cutaways and alternate angles – B-camera, C-camera, etc. The principle is to match the look of the B- and C-cameras to that of the A-camera.

Dealing with color science

Each camera manufacturer uses different color science for their products. Sony will have a distinctly different look from Canon or Panasonic. FilmConvert builds its plug-ins based on camera packs, which are each customized for a specific manufacturer and model in order to properly match that camera’s color science.

If you have a production that mixes a Sony FX9, an ARRI Amira, and a Panasonic GH5, then each uses a different camera pack. CineMatch is designed to work with Log/RAW/BRAW formats, so there are fewer packs available on the CineMatch site than on the Nitrate site. That’s because many of the prosumer cameras supported by Nitrate do not record in log and, therefore, wouldn’t be appropriate for CineMatch. Since CineMatch uses fewer camera packs, all currently-supported camera packs are included in the installer at this point in time.

The basics of matching

To start, disable any embedded LUT or remove any that you may have added. Next, apply the CineMatch effect to the clips on the timeline in Premiere Pro or as nodes in Resolve. On A-camera clips, set the appropriate source camera profile, but no target profile. For B-cams, C-cams, and other clips, set their source camera profile; however, set their target profile to match the A-camera source.

In a situation with an ALEXA A-cam and a Panasonic EVA1 as the B-cam, the ALEXA would only use the ALEXA source profile. The EVA1 would be set to the EVA1 source, but ALEXA as the target profile. Essentially you are moving all cameras into a color space matching the ARRI ALEXA Log-C color science.

To properly view the CineMatch output, apply the REC 709 transform. However, since CineMatch has converted all of these clips into a common log space, such as ARRI’s Log-C, you can also opt to leave this transform off within the clip filter and apply a conversion LUT at a different point, such as in an adjustment layer in Premiere Pro or as a timeline grading node in Resolve. This way, CineMatch is not limited to REC 709/SDR projects.

Additional color correction tools

Ideally the camera crew should have maintained proper and consistent exposure and white balance among cameras used on a common set-up. Even better if color charts have also been recorded at the start. In a perfect world, you’d now be done. Unfortunately, that’s never the case. You’ve unified the color space, but this doesn’t automatically match one clip to the next. CineMatch includes a comprehensive color correction toolkit to further match and adjust clips. There are white balance and exposure controls for quick adjustments.

If you use the split screen comparison view in Premiere Pro or Resolve, CineMatch HSL curves can be used to refine the match between source and target clips. As with Nitrate, there’s a full set of secondary color controls, including wheels, curves, and levels. Not only can you better match cameras to each other, but you can also use CineMatch to cover most basic grading needs without ever touching Resolve’s grading controls or Premiere’s Lumetri panel.

Working with CineMatch

Although this plug-in is marketed for camera matching, you can use it completely apart from that task. That’s primarily because of the camera packs. For example, when you film with a Panasonic GH5 in a log profile, no NLE offers a stock LUT that is correct for that camera. Generally you end up just correcting it without a LUT or applying a generic Panasonic V-Log LUT. That was designed for the Varicam’s color science and is not a perfect match for every other Panasonic camera. Close, but not spot-on. CineMatch lets you apply a correction that is tailor-made for each individual camera profile, thanks to FilmConvert’s development of a wide range of professional and prosumer camera packs.

The second advantage is that you can impart the look of other cameras. For example, I’m a fan of ARRI’s color science and really prefer the look of an ALEXA over most other cameras. I can apply CineMatch to a GH5 clip, set the source profile to GH5 and the target to ALEXA and impart a bit of that ARRI color to the GH5 clip. While it’s not a replacement for shooting with an ALEXA and the color conversion might not be absolutely perfect, it’s a nice adjustment that gives me a better image than working with that clip on its own.

Finally, if you own both CineMatch and FilmConvert Nitrate, it is possible to use the two in conjunction with each other. Just be very careful of the processes and their order. In the GH5/ALEXA example, make the profile conversion in CineMatch. Make no color adjustments there and don’t apply the REC 709 transform. Then add FilmConvert Nitrate, set its profile to the ARRI settings and make your film emulation and color adjustments to taste.

Original written for ProVideo Coalition.

©2020 Oliver Peters

Simple Color Workflow in FCPX

Building on the heels of the previous post, I’d like to cover five simple steps to follow when performing basic color correction, aka “grading,” in Final Cut Pro X. Not every clip or project will use all of these, but apply the applicable steps when appropriate.

Step 1. LUTs (color look-up tables)

There are technical and creative LUTs. Here we are talking only about technical camera LUTs that are useful when your footage was recorded in a log color space. These LUTs convert the clip from log to a display color space (REC 709 or other) and turn the clip’s appearance from flat to colorful. Each manufacturer offers specific LUTs for the profile of their camera models.

Some technical LUTs are already included with the default FCPX installation and can be accessed through the settings menu in the inspector. Others must be downloaded from the manufacturer or other sources and stored elsewhere on your system. If you don’t see an appropriate option in the inspector, then apply the Custom LUT effect and navigate to a matching LUT stored on your system.

Step 2. Balance Color

Next, apply the Balance Color effect for each clip. This will slightly expand the contrast of the clip and create an averaged color balance. This is useful for many, but not all clips. For instance, a clip shot during “golden hour” will have a warm, yellow-ish glow. You don’t want that to be balanced neutral. You have no control over the settings of the Balance Color process, other than to pick between Automatic and White Balance. Test and see when and where this works to your advantage.

Note that this works best for standard footage without a LUT or when the LUT was applied through the inspector menu. If the LUT was applied as a Custom LUT effect, then Balance Color will be applied ahead of the Custom LUT and may yield undesirable results.

Step 3. Color correction – color board, curves, or color wheels

This is where you do most of the correction to alter the appearance of the clip. Any or all of FCPX’s color correction tools are fine and the tool choice often depends on your own preference. For most clips it’s mainly a matter of brightening, expanding contrast, increasing or decreasing saturation, and shifting the hue offsets of lows (shadow area), midrange, and highlights. What you do here is entirely subjective, unless you are aiming for shot-matching, like two cameras in an interview. For most projects, subtlety is the key.

Step 4. Luma vs Sat

It’s easy to get carried away in Step 3. This is your chance to reign it back in. Apply the Hue/Sat Curves tool and select the Luma vs Sat Curve. I described this process in the previous post. The objective is to roll off the saturation of the shadows and highlights, so that you retain pure blacks and whites at the extreme ends of the luminance range.

Step 5. Broadcast Safe

If you deliver for broadcast TV or a streaming channel, your video must be legal. Different outlets have differing standards – some looser or stricter than others. To be safe, limit your luminance and chrominance levels by applying a Broadcast Safe effect. This is best applied to an adjustment layer added as a connected clip at the topmost level above the entire sequence. Final Cut Pro X does not come with an adjustment layer Motion template title, but there are plenty available for download.

Apply the Broadcast Safe effect to that adjustment layer clip. Make sure it’s set to the color space that matches your project (sequence) setting (typically Rec 709 for HD and 4K SDR videos). At its default, video will be clipped at 0 and 100 on the scopes. Move the amount slider to the right for more clipping when you need to meet more restrictive specs.

These five steps are not the end-all/be-all of color correction/grading. They are merely a beginning guide to achieve quick and attractive grading using Final Cut Pro X. Test them out on your footage and see how to use them with your own workflows.

©2020 Oliver Peters

5 Easy FCPX Color Tricks

Color correction plug-ins are certainly fun to use, but Final Cut Pro X has plenty of horsepower on its own. There are also a number of features and techniques that often get overlooked. Here are five simple tricks you can use to enhance the look of your videos. (Click any image to see an enlarged view.)

Balance Color / Match Color

Final Cut has offered the ability to auto balance the color of a shot and to match two shots to each other since the early days. Balance color analyzes a shot and corrects it to a neutral tonality. This is typically a “best guess,” based on either an automatic overall adjustment or one focusing on white balance.

You can select all of the clips in your timeline and balance them in a single command. Most of the time, automatic will result in a pleasing enhancement of the image. The exception is when there’s no clear white reference in the shot, like a close-up on fire. In that case, you’d want to retain the orange/yellow qualities of the shot. The balance color results are not adjustable (other than to select between automatic or white balance), so consider it a first step to be further enhanced by the other color correction tools.

Match color is different in that it corrects the tonality of a selected clip to match another clip in the timeline. Park on the clip, select match color, skim to the clip used for the match, click on that frame for a preview, and then click Apply Match if you like the preview results. A common application might be to match A and B cameras to each other.

Match color can be used creatively, as well. For example, let’s say you want your clips to match the tonality of shots from a particular movie. A great resource for film reference frames is the Shotdeck website (free if you register as a beta user). Find and download a reference frame. Import the image file and edit it to the end of your timeline. Now use match color for a selected clip and skim to that reference film image on your timeline.

Obviously it won’t make a sunny daytime shot look exactly like a moody night shot from Bladerunner, but it will adopt the overall tonality as closely as possible. Once you’ve completed the match, delete the reference image from your timeline.

Blend modes

Timeline clips include blend mode attributes. The default is the normal mode, which can easily be changed to screen, overlay, soft light, and so on. Blend modes (also called composite and transfer modes) are commonly used by graphic artists and designers, but they are also useful in creating special looks for video.

To start, option-drag a clip above itself to create a duplicate as a connected clip. You now have two versions of that clip in perfect sync with each other. Adjust the blend mode of the connected clip. Let’s say you have a low-contrast clip. When you drag it above itself and change the top clip’s mode to soft light, it will instantly result in more contrast and saturation.

This same trick can be used to create stylish effects. For example, when you add a gaussian blur to the lower clip, the results are a dreamy image. Add a sharpening filter to the top clip and now you’ve added some localized contrast. Push it far enough and the results are almost cartoon-like.

You can use this trick on single clips or the entire sequence. Simply compound the sequence and then option-drag the compound up to create a duplicate, connected clip. Select the desired blend mode of the connected clip and tweak for your look.

Hue/Saturation Curves – Luma vs Sat

When you push color correction to an extreme, the black and white detail in the image becomes contaminated by the color shift introduced by your correction. You no longer have anything that’s true black or white in the frame. When a colorist is creatively adjusting a shot, they still want to end up with nearly pure black at the darkest part of the image and pure white at the brightest.

One way to achieve this is with the Luma vs Sat curve in the Hue/Saturation Curves tool. From left to right, the base line represents the brightness range from black to white. Pulling the curve up or down increases or decreases saturation at the brightness value corresponding to that point along the line. To reduce color saturation for black and white, add a control point inwards from each end of the line. Now drag the outer points down to decrease saturation. Drag the inner points more or less towards the center to adjust the roll-off from full saturation to zero saturation. The more gentle the slope of the curve, the smoother the roll-off with fewer potential artifacts. However, the trade-off is that you may lose too much saturation overall. So adjust to taste.

Orange and Teal

Filmmakers are enamored with the “orange-and-teal” look – skin tones tend to be warm (orange), while middle-range portions of the image take on a teal color cast. This is aided by proper lighting, costuming, and set design that is conducive to such a grade. For example, walls and furnishings that are neutral, black, gray, or dark in some way tend to be easier to swing towards the teal than a background of bright red walls.

Final Cut Pro X does include a color preset (Spring Sun) that mimics this look. You can also achieve it with any of Final Cut’s grading tools, such as the color wheels. First, use any color tool to establish a normal grade. Then apply color wheels for the look. The objective is to isolate skin tones from the rest of the image. Add an image mask for the wheels and use the HSL keyer. Use the color picker to select a skin tone. View the mask in black-and-white and adjust the HSL settings for a smooth key. It’s OK if the mask includes more than only the skin tones. The smoothness of the key is important.

Once you are happy with the key, go back to the image and grade inside of the mask. Push the midrange color wheel to the orange as needed. Or keep the skin tones neutral if you want to preserve a natural appearance. Change the mask toggle to outside and shift the midrange, shadows, and master towards teal. Finally, add the Luma vs Sat adjustment as described above to restore natural blacks and whites to the shadow and highlight areas.

LUTs

Color look-up tables – LUTs – are used to apply the proper color profile for cameras. Custom LUTs can also be used creatively to create and preserve preset looks such as stylized grades, film stock emulation, and more. Final Cut cannot export LUTs, however, it can import any LUT in the standard .cube format. The internet offers plenty of options to purchase custom, creative LUTs.

Let’s take a more DIY approach. Several third-party color correction plug-ins, including FilmConvert Nitrate and Color Finale 2 Pro, allow the user to export the grade done within that plug-in as a self-contained LUT. Maybe you want to preserve the grade for future use that doesn’t depend on having the plug-in. Or maybe you don’t own that plug-in, but can collaborate with an editor/colorist who does. In that example, send your selected shots or sequence to them for a grade. Then, instead of returning the files to you with the baked-in look, simply export the grades for these clips as LUTs.

Back on your system, apply the Custom LUT effect to each clip and import the corresponding LUT. Make sure the settings match your color space (Rec 709 across the board for Rec 709 libraries and projects). In the case of Color Finale 2 Pro and FilmConvert Nitrate, most aspects of the grade done within their panels will be reproduced. Certain non-grading features, such as film grain emulation will not be included in the LUT. Overall, if I’m looking for a perfect match (same shot to same shot), then I’ve had more accurate results using Color Finale 2 Pro. This method is a great way of creating and transferring custom looks in a non-destructive manner.

I hope these simple tips will give you some ideas on how you can get more out of Final Cut Pro X to create and apply your own special touches.

Originally written for FCP.co.

©2020 Oliver Peters

Color Finale Connect – Remote Grading for FCPX

Remote workflows didn’t start with COVID, but that certainly drove the need home for many. While editing collaboration at a distance can be a challenge, it’s a far simpler prospect than remote color grading. That’s often a very interactive process that happens on premises between a colorist and a client, director, or cinematographer. Established high-end post facilities, like Company3 with locations in the US, Canada, and England, have pioneered remote color grading sessions using advanced systems like Resolve and Baselight. This allows a director in Los Angeles and a colorist in London to conduct remote, real-time, interactive grading sessions. But the investment in workflow development, hardware, and grading environments to make this happen is not inconsequential.

High-end remote grading comes to Final Cut Pro X

The Color Finale team has been on a quest to bring advanced grading tools to the Final Cut Pro X ecosystem with last December’s release of Color Finale 2. Many editors are working from home these days, so the team decided to leverage the frameworks for macOS and FCPX to enable remote grading in a far simpler method than with other grading solutions.

The result is Color Finale Connect, which is a Final Cut Pro X workflow extension currently in free public beta. Connect enables two or more Final Cut Pro X users to collaborate in near-real-time in a color grading session, regardless of their location. This review is in the context of long distance sessions, but Connect can also be used within a single facility where the participants might be in other parts of the building or in different buildings.

Color Finale Connect requires each user in a session to be on macOS Catalina, running licensed copies of Final Cut Pro X (not trial) and Color Finale 2.2 Pro (or higher). Download and install Color Finale Connect, which shows up as a Final Cut workflow extension. You can work in a Connect session with or without local media on every participant’s system. In order to operate smoothly and keep the infrastructure lightweight, person-to-person communication is handled outside of Connect. For example, interact with your director via Skype or Zoom on an iPad while you separately control Final Cut on your iMac.

Getting started

To start a session, each participant launches the Color Finale Connect extension within Final Cut. Whoever starts a session is the “broadcaster” and others that join this session are “followers.” The session leader (who has the local media) drags the Project icon to the Connect panel and “publishes” it. This generates a session code, which can be sent to the other participants to join the session from within their Connect extension panels.

Once a session is joined, the participants drag the Project icon from the Connect panel into an open FCPX Event. This generates a timeline of clips. If they have the matching local media, the timeline will be populated with the initial graded clips. If they don’t have media, then the timeline is populated with placeholder clips. Everyone needs to keep their Connect panel open to stay in the session (it can be minimized).

Data transfer is very small, since it consists mainly of Color Finale instructions; therefore, crazy-fast internet speeds aren’t required. It is peer-to-peer and doesn’t live anywhere “in the cloud.” If a participant doesn’t have local media installed, then as the session leader makes a color correction change in Color Finale 2 Pro, an “in-place” full-resolution frame is sent for that clip on the timeline. As more changes are made, the frames are updated in near-real-time.

The data communication is between Color Finale on one system and Color Finale on the others. All grading must happen within the Color Finale 2 Pro plug-in, not FCPX’s native color wheels or other plug-ins. The “in-place” frames support all native Final Cut media formats, such as H.264, ProRes, and ProRes RAW; however, formats that require a plug-in, like RED camera raw files, will not transmit “in-place” frames. In that case, the data applied to the placeholder frame is updated, but you won’t see a reference image.

This isn’t a one-way street. The session leader can enable any participant to also have control. Let’s say the session leader is the colorist and the director of photography is a participant. The colorist can enable remote control for the DP, which would permit them to make tweaks on their own system. This in turn would update back on the colorist’s system, as well as for all the other participants.

Color Finale Connect workflows

I’ve been testing a late-stage beta version of Connect and Color Finale 2.2 Pro and the system works well. The “in-place” concept is ingenious, but the workflow is best when each session member has local media. This has been improved with the enhanced proxy workflow updated in Final Cut Pro X 10.4.9. Let’s say the editor has the full-resolution, original media and generates smaller proxies – for example, 50% size H.264 files. These are small enough that you can easily send the Library and proxy media to all participants using services like WeTransfer, MASV, FileMail, or Frame.io.

One of the session members could be a favored colorist on the other side of the world. In this case, he or she would be working with the proxy media. If the editor and colorist are both able to control the session, then it becomes highly interactive. Formats like RED don’t pose a problem thanks to the proxy transcodes, as long as no local changes are made outside of the Color Finale plug-in. In other words, don’t change the RED raw source settings within this session. Once the colorist has completed the grade using proxy media, those grading settings would be updated through a Connect session on the editor’s system where the original media resides.

Color management

How do you know that your client sees the color in the same way as you do on a reference display? Remote color grading has always been hampered by color management and monitor calibration. It would, of course, be ideal for each participant in the session to have Blackmagic or AJA output hardware connected to a calibrated display. If there is an a/v output for FCPX, then the Connect session changes will also be seen on that screen. But that’s a luxury most clients don’t have.

This is where Apple hardware, macOS, and Final Cut Pro X’s color management come to the rescue and make Color Finale Connect a far simpler solution than other methods. If both you and your client are using Apple hardware (iMac, iMac Pro, Pro Display XDR) then color management is tightly controlled and accurate. First make sure that macOS display settings like True Tone and Night Shift are turned off on all systems. Then you are generally going to see the same image within the Final Cut viewer on your iMac screen as your client will see on theirs.

The one caveat is that users still have manual control of the screen brightness, which can affect the perception of the color correction. One tip is to include a grayscale or color chart that can be used to roughly calibrate the display’s brightness setting. Can everyone just barely see the darkest blocks on the chart? If not, brighten the display setting slightly. It’s not a perfect calibration, but it will definitely get you in the ballpark.

Color Finale 2 Pro turns Final Cut Pro X into an advanced finishing solution. Thanks to the ecosystem and extensions framework, Final Cut opens interesting approaches to collaboration, especially in the time of COVID. Tools like Frame.io and Postlab enable better long-distance collaboration in easier-to-use ways than previous technologies. Color Finale Connect brings that same ease-of-use and efficient remote collaboration to FCPX grading. Remember this is still a beta, albeit a stable one, so make sure you provide feedback should any issues crop up.

Originally written for FCP.co.

©2020 Oliver Peters

Working with ACES in DaVinci Resolve

In the film days, a cinematographer had a good handle on what the final printed image would look like. The film stocks, development methods, and printing processes were regimented with specific guidelines and limited variations. In color television production, up through the early adoption of HD, video cameras likewise adhered to the standards of Rec. 601 (SD) and Rec. 709 (HD). The advent of the video colorist allowed for more creative looks derived in post. Nevertheless, video directors of photography could also rely on knowing that the image they were creating would translate faithfully throughout post-production.

As video moved deeper into “cinematic” images, raw recording and log encoding became the norm. Many cinematographers felt their control of the image slipping away, thanks to the preponderance of color science approaches and LUTs (color look-up tables) generated from a variety of sources and applied in post. As a result, the Academy Color Encoding System (ACES) was developed as a global standard for managing color workflows. It’s an open color standard and method of best practices created by filmmakers and color scientists under the auspices of the Science and Technology Council of the Academy of Motion Picture Arts and Sciences (AMPAS, aka “The Academy”). To dive into the nuances of ACES – complete with user guides – check out the information at ACEScentral.com.

The basics of how ACES works

Traditionally, Rec. 709 is the color space and gamma encoding standard that dictates your input, timeline, and exports for most television projects. Raw and log recordings are converted into Rec. 709 through color correction or LUTs. The color gamut is then limited to the Rec. 709 color space. Therefore, if you later try to convert a Rec. 709 ProResHQ 4:2:2 master file into full RGB, Rec. 2020, HDR, etc., then you are starting from an already-restricted range of color data. The bottom line is that this color space has been defined by the display technology – the television set.

ACES is its own color space designed to be independent of the display hardware. It features an ultra-wide color gamut that encompasses everything the human eye can see. It is larger than Rec. 709, Rec. 2020, P3, sRGB, and others. When you work in an ACES pipeline, ACES is an intermediate color space not intended for direct viewing. In other world, ACES is not dictated by current display technology. Files being brought into ACES and being exported for delivery from ACES pass through input and output device transforms. These are mathematical color space conversions.

For example, film with an ARRI Alexa, record as LogC, and grade in a Rec. 709 pipeline. A LogC-to-REC709 LUT will be applied to the clip to convert it to the Rec. 709 color space of the project. The ACES process is similar. When working in an ACES pipeline, instead of applying a LUT, I would apply an Input Device Transform (IDT) specific for the Alexa camera. This is equivalent to a camera profile for each camera manufacturer’s specific color science.

ACES requires one extra step, which is to define the target device on which this image will be displayed. If your output is intended to be viewed on television screens with a standard dynamic range, then an Output Device Transform (ODT) for Rec. 709 would be applied as the project’s color output setting. In short, the camera file is converted by the IDT into the ACES working color space, but is viewed on your calibrated display based on the ODT used. Under the hood, ACES preserves all of the color data available from the original image. In addition to IDTs and ODTs, ACES also provides for Look Modification Transforms (LMT). These are custom “look” files akin to various creative LUTs built for traditional Rec. 709 workflows.

ACES holds a lot of promise, but it is still a work-in-progress. If your daily post assignments don’t include major network or studio deliverables, then you might wonder what benefit ACES has for you. In that case, yes, continuing to stick with a Rec. 709 color pipeline will likely be fine for a while. But companies like Netflix are behind the ACES initiative and other media outlets are bound to follow. You may well find yourself grading a project that requires ACES deliverables at some point in the future.

There is no downside in adopting an ACES pipeline now for all of your Resolve Rec. 709 projects. Working in ACES does not mean you can instantly go from a grade using a Rec. 709 ODT to one with a Rec. 2020 ODT without an extra trim pass. However, ACES claims to make that trim pass easier than other methods.

The DaVinci Resolve ACES color pipeline

Resolve has earned a position of stature within the industry. With its low price point, it also offers the most complete ACES implementation available to any editor and/or colorist. Compared with Media Composer, Premiere Pro, or Final Cut Pro X, I would only trust Resolve for an accurate ACES workflow at this point in time. However, you can start your edit in Resolve as Rec. 709 – or roundtrip from another editor into Resolve – and then switch the settings to ACES for the grade and delivery. Or you can start with ACES color management from the beginning. If you start a Resolve project using a Rec. 709 workflow for editing and then switch to ACES for the grade, be sure to remove any LUTs applied to clips and reset grading nodes. Those adjustments will all change once you shift the settings into ACES color management.

To start with an ACES workflow, select the Color Management tab in the Master Settings (lower right gear icon). Change Color Science to ACEScct and ACES version 1.1. (The difference between ACEScc and ACEScct is that the latter has a slight roll-off at the bottom, thus allowing a bit more shadow detail.) Set the rest as follows: ACES Input Device Transform to No Input Transform. ACES Output Device Transform to Rec. 709 (when working with a calibrated grading display). Process Node LUTs in ACEScc AP1 Timeline Space. Finally, if this is for broadcast, enable Broadcast Safe and set the level restrictions based on the specs that you’ve been supplied by the media outlet.

With these settings, the next step is to select the IDT for each camera type in the Media page. Sort the list to change all cameras of a certain model at once. Some media clips will automatically apply an IDT based on metadata embedded into the clip by the camera. I found this to be the case with the raw formats I tested, such as RED and BRAW. While an IDT may appear to be doing the same thing as a technical LUT, the math is inherently  different. As a result, you’ll get a slightly different starting look with Rec. 709 and a LUT, versus ACES and an IDT.

Nearly all LUTs are built for the Rec. 709 color space and should not be used in an ACES workflow. Yes, you can apply color space transforms within your node structure, but the results are highly unpredictable and should be avoided. Technical camera LUTs in Resolve were engineered by Blackmagic Design based on a camera manufacturer’s specs. They are not actually supplied as a plug-in by the manufacturer to Blackmagic. The same is true for Apple, Avid, and Adobe, which means that in all cases a bit of secret sauce may have been employed. Apple’s S-Log conversion may not match Avid’s for instance. ACES IDTs and ODTs within Resolve are also developed by Blackmagic, but based on ACES open standards. In theory, the results of an IDT in Resolve should match that same IDT used by another software developer.

Working with ACES on the Color page

After you’ve set up color management and the transforms for your media clips, you’ll have no further interaction with ACES during editing. Likewise, when you move to the Color page, your grading workflow will change very little. Of course, if you are accustomed to applying LUTs in a Rec. 709 workflow, that step will no longer be necessary. You might find a reason to change the IDT for a clip, but typically it should be whatever is the correct camera profile for the associated clip. Under the hood, the timeline is actually working in a log color space (ACEScc AP1); therefore, I would suggest grading with Log rather than Primary color wheels. The results will be more predictable. Otherwise, grade any way you like to get the look that you are after.

Currently Resolve offers few custom look presets specific to the ACES workflow. There are three LMTs found under the LUTs option / CLF (common LUT format) tab (right-click any node). These include LMT Day for Night. LMT Kodak 2383 Print Emulation, LMT Neon Suppression. I’m not a fan of either of the first two looks. Quite frankly, I feel Resolve film stock emulations are awful and certainly nowhere near as pleasing as those available through Koji Advance or FilmConvert Nitrate. But the third is essential. The ACES color space has one current issue, which is that extremely saturated colors with a high brightness level, like neon lights, can induce image artifacts. The Neon Suppression LMT can be applied to tone down extreme colors in some clips. For example, a shot with a highly saturated red item will benefit from this LMT, so that the red looks normal.

If you have used LUTs and filters for certain creative looks, like film stock emulation or the orange-and-teal look, then use PowerGrades instead. Unlike LUTs, which are intended for Rec. 709 and are typically a “black box,” a PowerGrade is simply a string of nodes. Every time you grab a still in the Color page, you have stored that series of correction nodes as a PowerGrade. A few enterprising colorists have developed their own packs of custom Resolve PowerGrades available for free or sale on the internet.

The advantages are twofold. First, a PowerGrade can be applied to your clip without any transform or conversion to make it work. Second, because these are a series of nodes, you can tweak or disable nodes to your liking. As a practical matter, because PowerGrades were developed with a base image, you should insert a node in front of the added PowerGrade nodes. This will allow you to optimize your image for the settings of the PowerGrade nodes and provide an optimal starting point.

Deliverables

The project’s ODT is still set to Rec. 709, so nothing changes in the Resolve Deliver page. If you need to export a ProResHQ master, simply set the export parameters as you normally would. As an extra step of caution, set the Data Levels (Advanced Settings) to Video and Color Space and Gamma Tags to Rec. 709, Gamma 2.4. The result should be a proper video file with correct broadcast levels. So far so good.

One of the main reasons for an ACES workflow is future proofing, which is why you’ve been working in this extended color space. No common video file format preserves this data. Furthermore, formats like DNxHR and ProRes are governed by companies and aren’t guaranteed to be future-proofed.

An ACES archival master file needs to be exported in the Open EXR file format, which is an image sequence of EXR files. This will be a separate deliverable from your broadcast master file. First, change the ACES Output Device Transform (Color Management setting) to No Output Device and disable Broadcast Safe limiting. At this point all of your video clips will look terrible, because you are seeing the image in the ACES log color space. That’s fine. On the Deliver page, change the format to EXR, RGB float (no compression), and Data Levels to Auto. Color Space and Gamma Tags to Same As Project. Then Export.

In order to test the transparency of this process, I reset my settings to an ODT of Rec. 709 and imported the EXR image sequence – my ACES master file. After import, the clip was set to No Input Transform. I placed it back-to-back on the timeline against the original. The two clips were a perfect match: EXR without added grading and the original with correction nodes. The one downside of such an Open EXR ACES master is a huge size increase. My 4K ProRes 4444 test clip ballooned from an original size of 3.19GB to 43.21GB in the EXR format.

Conclusion

Working with ACES inside of DaVinci Resolve involves some different terminology, but the workflow isn’t too different once you get the hang of it. In some cases, camera matching and grading is easier than before, especially when multiple camera formats are involved. ACES is still evolving, but as an open standard supported globally by many companies and noted cinematographers, the direction can only be positive. Any serious colorist working with Resolve should spend a bit of time learning and getting comfortable with ACES. When the time comes that you are called upon to deliver an ACES project, the workflow will be second nature.

Originally written for Pro Video Coalition.

©2020 Oliver Peters