Grading through digital bipacks

When you hear someone use the term bipack, you think they are making the word up or just BS’ing you. In fact, bipack refers to an old technique used to create in-camera film effects. Film timers also used the technique to create certain color effects. In modern times, we are really referring to ways that involve blending or superimposing images and this has a direct relationship on tricks you can use in color correction.

The concept of blending two images with different values is a lot like working with layers and blend modes in Photoshop. Some color correction applications, like SpeedGrade, also use a Photoshop-style system of layers. You aren’t limited to color correction applications, though, because these exact same tricks can be used in any NLE. For example, editors have frequently built a look referred to as “instant sex”, which is a technique for adding highlight glows by compositing copies of the same clip on two video layers. The process is easiest with NLEs and compositors like Motion or After Effects that offer composite modes. I find Apple Final Cut Pro X to be a good NLE for these tricks, because the interface design makes it easy to blend and adjust two stacked clips.

I’ll cover several quick examples of how you might use this technique. (Click any of these images for an expanded view.) For clips, I’ve grabbed shots from Afterglow, a short film photographed by John Brawley to promote the release of the Blackmagic Cinema Camera. The source clips are QuickTime ProRes files was a BMD Film (flat, log) gamma profile. To these I’ve added a Pomfort LUT filter normally used for ARRI Alexa Log-C. This corrects the clips back to their intended REC 709 appearance and becomes my starting point.

To stack clips in FCP X, simply edit the clip to the primary storyline and the option-drag it up to duplicate a version as an in-sync, connected clip. Since composite modes often create illegal video levels, I place an adjustment layer clip (a modified Motion title) on top, with a broadcast safe filter added to it.

In this first example, the bottom clip is changed to black-and-white by reducing the saturation in the FCP X color board. The top clip’s composite mode is set to Soft Light. Grading for the right tonal qualities becomes a dance between the settings on the two layers and the opacity value of the top clip’s compositing mode.

If I add a Gaussian blur to the lower clip, change the compositing mode of the top clip to Overlay and tweak the color board settings of the two clips, the look changes from harsh to glamour.

In this billiards shot I’m using the Soft Light mode again, but this time I have tinted the lower clip to a slight teal cast. The top clip is a vibrant orange, but the combination of the two ends up with the more normal-looking and popular orange-and-teal grade.

In this balcony shot I’m using the Overlay mode and have added a slight directional blur to the top layer. The bottom layer is desaturated with a slight tint while the top layer is more vibrant. Combined they have a high-contrast, bleached look.

In this final example, I’ve reversed some items. The top layer is set to the Multiply mode at 80% opacity and I’ve made it black-and-white. The color correction is again a matter of compensating between the two layers to get the right feel.

When I add a Gaussian blur to the top clip the look changes from harsh to a nice, diffused appearance.

© 2012 Oliver Peters

Magic Bullet PhotoLooks 2

Red Giant Software launched the preset-based “looks” market, when it originally released the browser version of Magic Bullet Looks. Visual effects director and software designer Stu Maschwitz overhauled the original product to create a self-contained color correction and “looks creation” interface, where tools were grouped according to how they fit into the flow from in-front of the camera to post. Magic Bullet Looks ships with tools and a number of presets, which can quickly be previewed on an image. The software is built as a separate application that is linked into most standard NLEs and compositors as a plug-in. This design spawned a still photography version, called PhotoLooks, which uses the same basic engine. For still photography, PhotoLooks installs as a plug-in to Adobe Photoshop and Lightroom and Apple Aperture.

Last year Red Giant Software brought out Magic Bullet Looks 2.0, which is also sold as part of the Magic Bullet Looks Suite 11. This featured a more streamlined Looks interface and additional tools, like Cosmo (a skin smoothing tool), but the PhotoLooks version was stuck with the old skin. Now the two have parity, with the recent update of the suite and PhotoLooks 2.0. Purchase PhotoLooks separately or get it included with the suite. Once again, both Magic Bullet Looks (for video) and PhotoLooks (for stills) feature a consistent appearance and a common set of tools and presets.

Magic Bullet PhotoLooks 2.0 is available as a plug-in to Photoshop, Aperture or Lightroom, but may also be accessed by launching the PhotoLooks application. When you use it as a plug-in, you gain the benefits of round-tripping between the applications. In Aperture and Lightroom, both before and after version are saved, to guarantee that the process is non-destructive. If you open PhotoLooks separately, you can import JPEGs, PNGs and TIFFs, but the adjusted image can only be saved as a JPEG. Custom looks can also be exported for use elsewhere.

Along with the new interface and Cosmo, other new features include four new scopes, faster GPU-enabled processing and 3-way color correction tools based on Magic Bullet’s popular Colorista filter. Creating an original look is as simple as dragging a tool into one of the categories (subject, matte, lens, camera, post) and then tweaking the setting to your liking. A tool isn’t limited to a specific category, so “post” tools can be applied in the “subject” position, as well as the other way around. You are simply creating a chain of filter effects, much like audio engineers do with audio filters. Once you get the desired result either save that as a new preset or exit back to the host program, where the image will appear with that look applied to it.

Originally written for Digital Video magazine (NewBay Media, LLC).

©2012 Oliver Peters

Demystifying Color Grading with FCP X

It’s time to dive in deeper and see how Final Cut Pro X can solve your color grading issues. A lot of FCP X fans like to say that Apple rolled Color into FCP X, but that’s pretty far from the truth. Some features from Color have counterparts in X, but the two applications are completely different and the number of tools at your disposal in Color greatly exceeds the toolset in X. Furthermore, X has no real color correction workflow as you’d find in any grading tool, FCP 7 or other NLE’s like Avid Symphony. That being said, rest assured that Apple definitely improved the color processing pipeline inside FCP X. The way grading affects the image is cleaner and the final results are an improvement over FCP 7. If you can live with the current limitations, you can definitely do quality work within the Final Cut Pro X interface.

The color correction tools center on the tabbed color board section of the inspector pane. The color board offers three tabs for exposure, saturation and color (tint). There’s a submenu accessed from the gear icon for various presets. These provide a quick starting point for the editor who isn’t experienced with color correction. You can also save your own presets from this menu. A number of useful color-oriented filters can also be found in the Looks and Stylize effects categories. If you wish to expand your color board preset options, check out the Lustre Grade Presets from Color Grading Central.

The color board tabs each have four pucks or sliders for global, shadow, midtone and highlight range controls. The exposure and saturation tabs only allow the pucks to go up or down to increase or decrease each value. The color (tint) tab has pucks that can be moved over the entire color swatch range. This tab uses a split-toning approach, rather than the customary hue offset/color wheel model. Move a puck up or down and over a specific color to add or subtract that color’s intensity from one of the four ranges.

The power of the color board comes into play when you start to use more than one instance of the correction. You can apply full screen corrections or have a selection restricted by an HSL key or a shape mask. Corrections may be applied to the inside or outside of a mask. As you’ll see in the examples that follow, you can stack several full screen corrections along with several masked corrections for elaborate grading of footage. Since color board settings are clip modifiers, they aren’t very taxing on real-time playback.

I’ve previously written about the FCP X color correction tools, as well as some of the filters and filter suites available for X. In addition, check FCP.co, Alex Gollner’s site and Ripple Training for more options. When I wrote “Demystifying Color Grading II,” I used the short film Convergence as an example. Director Martin Scanlan and DoP Steve Lawes shot it with a pre-release Sony F3 and posted the ungraded version at Vimeo, inviting users to download it and to play with. I’ve revisited Convergence in this post. As before, I downloaded the H.264 file, converted it to ProResLT and used that inside FCP X. Since that’s a lot of compression and recompression, you’ll have to excuse some of the images if there’s a bit of crunchiness to them.

Color correction – aka color grading – has two objectives – technical and aesthetic. For the technical, you want to make sure balance, exposure and contrast are right and that shots are consistent within a scene. Since these clips are ungraded images straight from the camera, the starting point for each shot will look a bit flat and somewhat green. A lot of my correction was simply to create a punchier image and to reduce the green cast. Or in some cases, push further in that direction as a choice. The second part of grading is to add a subjective look. Often this verges into “relighting” a shot by brightening some portions and darkening others – much like burning and dodging in photography. The point is to focus the viewer’s attention where you want it to be and to reduce or eliminate distractions.

I’ve posted grades on 21 shots. These are not meant to be consistent nor necessarily how I would actually grade this short film. These are merely an assortment of directions you can go in using the color board, plus a few other filters. Feel free to click on any of the images in this post and at the links within the steps to see a more detailed view.

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Shot 1

a. Ungraded original   [Click to view]

b. Tokyo ShadowsHighlights filter for overall tonal adjustment   [Click to view]

c. Color board 1 – bright and more normal flesh tone   [Click to view]

d. Color board 2 – mask to create vignette – darken outside of mask   [Click to view]

e. Final after vignette is applied   [Click to view]

Objective – Brighten the shot and get a more natural skin tone. Emphasis lighting focus on the actor.

Shot 2

a. Ungraded original   [Click to view]

b. Color board 1 – orange and teal tonal style   [Click to view]

c. Color board 2 – HSL key to isolate face and make it more normal   [Click to view]

e. Color board 3 – HSL key to isolate scarf and reduce intensity   [Click to view]

Objective – End up with an “orange & teal” tonality, without fluorescent reds in the scarf as a byproduct.

Shot 3

a. Ungraded original   [Click to view]

b. Tokyo CrossProcess filter to alter tones and add glow   [Click to view]

c. Color board 1 – adjust tonal range – more golden   [Click to view]

d. Color board 2 – shape mask for gradient correction at the top   [Click to view]

Objective – A more striking shot with an obvious “over-the-top” tint to the sky.

Shot 4

a. Ungraded original   [Click to view]

b. Color board 1 – more contrast and more blue   [Click to view]

c. Color board 2 – HSL key to isolate grass and reduce intensity   [Click to view]

d. Color board 3 – shape mask to add vignette and darken edges   [Click to view]

Objective – Bring the actor out of an otherwise murky shot.

Shot 5

a. Ungraded original   [Click to view]

b. Color board 1 – more contrast and saturation   [Click to view]

c. Color board 2 – add mask for face   [Click to view]

d. Color board 2 – brighten area in mask   [Click to view]

e. Color board 3 – shape mask to add vignette and darken edges   [Click to view]

Objective – Add more snap to the image and brighten the actor’s face.

Shot 6

a. Ungraded original   [Click to view]

b. Color board 1 – tonal change to make it more blue   [Click to view]

c. Color board 2 – HSL key to isolate face and make it more orange   [Click to view]

Objective – Another variation to the “orange & teal” look with definite blue casts to the dark areas.

Shot 7

a. Ungraded original   [Click to view]

b. Color board 1 – more contrast, less saturation   [Click to view]

Objective – Add more snap to the image. Moving in the direction of a “bleach bypass” look without going that extreme.

Shot 8

a. Ungraded original   [Click to view]

b. Tokyo Tilt-Shift filter (applied twice) to blur outer edge   [Click to view]

c. FCP X Teal & Orange filter for stylized look   [Click to view]

d. FCP X Vignette filter to darken outer edge   [Click to view]

e. Color board 1 – to adjust image tonality   [Click to view]

Objective – A dreamier look suitable for flashbacks, using selective focus.

Shot 9

a. Ungraded original   [Click to view]

b. FxFactory / DVShade EasyLooks for correction and glows   [Click to view]

Objective – A dreamier look suitable for flashbacks, using diffusion, glows and added warmth.

Shot 10

a. Ungraded original   [Click to view]

b. Octo filter to mask right edge   [Click to view]

c. Set filter to blur for swing-tilt effect   [Click to view]

d. Octo filter 2 set to vignette to darken right edge   [Click to view]

e. Color board to change tonality towards browns   [Click to view]

Objective – Feature the actor better in the shot by using selective focus and changing the overall tonality of the shot.

Shot 11

a. Ungraded original   [Click to view]

b. FCP X Aged Film filter to add grain   [Click to view]

c. Color board 1 – more contrast, less saturation   [Click to view]

d. Color board 2 – shift tonality towards blue   [Click to view]

Objective – Create a distressed look by adding grain and more blue tones for a cooler look. Also added touches of the “bleach bypass” look (more contrast, lower saturation).

Shot 12

a. Ungraded original   [Click to view]

b. Pomfort AlexaLook2Video LUT filter – misused for effect   [Click to view]

Objective – Adding more snap to the image. In this case, I’m pushing it to an extreme by using an ALEXA LUT filter not intended for this purpose.

Shot 13

a. Ungraded original   [Click to view]

b. Tokyo ShadowsHighlights for tonality, glow and diffusion   [Click to view]

c. Color board 1 – more contrast and more orange skin tones   [Click to view]

d. Color board 2 – HSL key to isolate face – more orange tones   [Click to view]

Objective – Adding more snap to the image. In this case, I’m pushing it to an extreme by using highlight glows and a push to the orange with her skin tones.

Shot 14

a. Ungraded original   [Click to view]

b. FCP X Super 8mm filter for tonal style and grain   [Click to view]

c. Color board 1 – slightly darker and less saturated   [Click to view]

Objective – A more “filmic” look, with a touch of distress.

Shot 15

a. Ungraded original   [Click to view]

b. Tokyo CrossProcess filter to tonal, glow and vignette effects   [Click to view]

Objective – This is a cross-process look. The idea stems from film processing where chemicals for one film stock are used to process a different stock, resulting in color contamination. In this case, a shift towards blues and greens.

Shot 16

a. Ungraded original   [Click to view]

b. Color board 1 – tonal adjustments   [Click to view]

c. FCP X Colorize filter to make image warmer   [Click to view]

d. Alex4d Soft Focus filter to add diffusion   [Click to view]

Objective – A more romantic feel, using diffusion and warmth.

Shot 17

a. Ungraded original   [Click to view]

b. Color board 1 – tonal adjustments   [Click to view]

c. Color board 2 – shape mask for vignette to darker right half   [Click to view]

d. Color board 3 – HSL key to isolate and change contrast on face   [Click to view]

Objective – Relight the shot to focus in on the actress.

Shot 18

a. Ungraded original   [Click to view]

b. Color board 1 – tonal adjustment   [Click to view]

c. Color board 2 – shape mask to highlight woman   [Click to view]

d. Color board 2 – brighten inside of mask – woman’s face   [Click to view]

e. Color board 3 – shape mask to highlight and brighten man   [Click to view]

f. Color board 4 – HSL key to isolate and reduce intensity of lights in background   [Click to view]

g. Color board 5 – HSL key to isolate blues in sky and change the tonality   [Click to view]

Objective – Relight the shot to focus in on the two actors. Also darken the sky for a more brooding feel.

Shot 19

a. Ungraded original   [Click to view]

b. FxFactory / PHYX Techni2Color filter to shift tonality   [Click to view]

c. FxFactory / PHYX BleachBypass filter to brighten image   [Click to view]

d. FxFactory / PHYX GlowDark filter to diffuse image   [Click to view]

e. Color board adjustment to shift tonality for stylized effect   [Click to view]

Objective – Change the entire style of the shot. The pseudo “Technicolor” process adds a blue shift and the “bleach bypass” can be used for color correction with less obvious effect. The Glow Dark filter controls local contrast adding subtle diffusion.

Shot 20

a. Ungraded original   [Click to view]

b. FCP X Glow filter to brighten highlights   [Click to view]

c. Color board 1 – tonal adjustment   [Click to view]

d. Color board 2 – shape mask to isolate and darken bright light in background   [Click to view]

e. Color board 3 – shape mask to isolate area outside of face   [Click to view]

f. Color board 3 – darken area outside of mask for vignette   [Click to view]

Objective – Relight the shot to focus in on the actress. Also to de-emphasize the large light source in the background.

Shot 21

a. Ungraded original   [Click to view]

b. Color board 1 – tonal adjustment   [Click to view]

c. Color board 2 – shape mask to isolate person   [Click to view]

d. Color board 2 – brighten area inside of mask   [Click to view]

e. Color board 3 – HSL key to isolate background lights and make them more yellow   [Click to view]

f. Color board 4 – shape mask to darken edge for vignette   [Click to view]

Objective – Focus attention more on the actor. Change highlight tones in the background.

©2012 Oliver Peters

Getting started with Adobe SpeedGrade

The addition of SpeedGrade to Adobe’s Creative Suite 6 line-up gives users yet another powerful tool for film-style color correction and grading. The Adobe SpeedGrade interface is minimalist with few menu commands, so it will help for new users to seek out some of the online tutorials before diving into their first project. I will briefly provide some pointers here to help you get started.

Configuration

Adobe SpeedGrade functions on dual and single monitor systems, but video output is only possible with SDI-equipped NVIDIA graphics cards (PC only). If you have a second display connected to a DVI or DisplayPort connection, then the video viewer can be moved to the second screen. In the Settings–Display menu, enable “Dual Display Output”. If you normally place the system menu on the right hand display of a Mac, then it’s possible that the interface will cover the viewer, leaving you to wonder where it went. In that case, a minus value for the left edge will reveal the image. I have two 20” Apple Cinemas, so a left value of -1680 pixels places the viewer on my left display and the rest of the interface on the right.

Getting media into SpeedGrade

There are currently three ways to bring media into SpeedGrade. If you are cutting in Premiere Pro CS6, then you can use the “Send to Adobe SpeedGrade” command. This will render intermediate, uncompressed DPX frames, which will relink automatically to clips on a new SpeedGrade timeline. The need for intermediate files is because SpeedGrade doesn’t support some codecs that are native to Premiere Pro, like AVC-Intra. DPX files maintain quality, but are unlikely to play in real-time without a fast drive array. You can also bring a complete show as a single file into SpeedGrade and use the scene detection function to “notch” the timeline at the cuts. The fastest method for most projects is to export an EDL (edit decision list) from your NLE, which will reconnect to the original media within SpeedGrade. For instance, if you are cutting a project made up of ProRes media, then this would be the preferred method.

Media and file imports are handled through the tabs at the top left corner of the interface. Next to the Monitor tab is a file navigation tab, which often defaults to the Desktop. Additional tabs can be added by clicking the plus symbol. Set the file type pulldown menu to “all files” and navigate to the location of the EDL file. Select the correct EDL and click the plus symbol in the corner of the selected icon for that EDL. This will add the blank EDL clips to a new timeline. Next, to reconnect the media files, set the file formats pulldown menu to “Movie Formats” and navigate to the location of your camera files.

At the bottom of the SpeedGrade interface, go to Timeline–Reels and choose “Load from Desktop”. This will now link all selected movie files based on the info from the EDL and populate your timeline clips with video. Make sure all frame rate settings match throughout the system, otherwise you might get an error message when combining media and EDLs.

Understanding the layout

Once you are ready to start grading, you’ll want to set the interface to the Monitor tab in the top portion and the Look tab in the bottom. The thin timeline strip separates these two portions. The Monitor is the place for scopes, transport controls and viewer, except when the viewer has been moved to a second screen. You can step through your clips by dragging the playhead underneath timeline bar, by using on-screen transport buttons or JKL keyboard commands.

One unique SpeedGrade function is the ability to have numerous “live” playheads at different points along the timeline. All can simultaneously playback in real-time, depending on the horsepower of your system. If you want to create a second (or more) playhead location, Command+Drag (Mac) the active playhead by its handle to a new clip on the timeline. This duplicates the playhead at that new location. You can click between the playheads for active color correction on each, which is great for shot-matching. The offset is maintained, and you’ll see both viewer windows update in real-time as the timeline is played. Multiple playheads can be configured to fit the screen or as splits. Their layout is controlled in the Timeline-View tab. To remove unwanted playheads, simply grab any inactive playhead by the handle and drag it to a blank portion of the interface until a red “x” appears in it and then let go.

Starting color correction

The Look tab is where the action occurs. This section is divided into three panes for layers, controls and presets. Layers are similar to those in Photoshop and can hold primary or secondary corrections, filter effects and LUT (look-up table) adjustments. You can show or hide a layer, adjust its opacity and change the stacking order.

The color correction controls appear in the center of the Look tab. Depending on preference, levels and balance can be adjusted using color wheels and sliders, only sliders or by numerical entry. The control of color parameters is very extensive, with four settings groups divided into overall, shadows, midtones and highlights. In the color wheel view, these are similar to the way such controls work on competing systems, using an offset/gamma/gain model. However, there are also sliders for input and output saturation, contrast and pivot point, and temperature and magenta (tint). Each of the shadow, midtone and highlight groups also have luma range sliders, which control the cross-over from shadow to midtone and midtone to highlight. This design leaves all the controls right in front of you and provides more versatility than other systems using typical hue offset color wheels and curves.

The bottom portion of the Look panel is reserved for preset and saved grades. SpeedGrade ships with a number of LUTs, filters and preset looks and masks. These preset examples are stored inside the application package and this is one of the few Mac OS X applications, which allows you to access media from inside the otherwise hidden, application package contents. Here you can pick from various Bleach Bypass, Day for Night, Sepia and other stylistic presets. I suggest copy-and-pasting these from the package contents to a documents folder for easier access. You can also save your own grades in the .look file format. These .look files may also be used in Photoshop CS6 and After Effects CS6.

Beyond the primary

When establishing a grade, you are adjusting the initial primary layer for a clip. If you want to give the client options – like a cool look or a warm look – simply add another primary layer, create the alternate color correction and toggle the eyeball icon between the two layers to show/hide the results for each. You can also mix between two or more full screen primaries by adjusting their opacity sliders. Click the inside or outside mask icon on a primary layer to “window” an area or apply a vignette effect. To control the mask, move to the Mask tab, select and apply one of the presets or create a custom shape. SpeedGrade includes a very handy on-screen widget for adjusting all of the mask parameters. The Mask tab is also where you’ll finder SpeedGrade’s tracker.

Secondary layers are used for HSL keying, such as isolating the color of a shirt to change its saturation or hue. In the Layers pane, add a secondary layer, which will reveal color-picker and keying tools, as well as a modified set of color correction controls. To view the keyed area, select a Gray-out value from the pulldown menu. Once you have tweaked the key the way you’d like it, you can select the alpha or inverted-alpha icon in the Layers pane to control how the correction is applied. One handy tip is to go overboard on a correction and then back off of the intensity by adjusting that layer’s opacity. Lastly, you can also apply a mask to a secondary, if you need to further restrict the keyed area.

One final type of correction is to add a custom look layer in the Layers pane. Clicking the plus sign on the bottom of the Layers pane brings up a pulldown menu with a long list of filters (emboss, blur, bloom, etc.) and looks (bleach bypass, day for night, etc.). When you apply one of these, adjustment parameters appear in the center of the Look tab. So, Gaussian blur control sliders appear where color wheels are usually seen when you select between a primary and a custom layer in the Layers pane.

In addition to building grades for each clip, it’s also possible to apply grades to all or a portion of the timeline. For example, if you want a common vignette on all clips, it may be more desirable to apply a grading layer across the entire timeline, set the vignette, which would then be applied to all of the clips below. This timeline grading layer can also be toggled on and off using the familiar eyeball icon next to the timeline track.

Output

The last step is rendering your work. There is currently no roundtrip back into Premiere Pro or any other NLE from SpeedGrade. To access the render controls, click the Output tab in the upper right corner of the interface. This is where you can set render format, framing, target location and other settings. If there’s no format preset for your desired target – for instance, ProResLT – simply create a new one. You can render out the complete timeline as a single, flattened movie file or the individual timeline clips with handles and source timecode. Separate clips with the new, baked in color correction can be reconnected to an edited timeline in any NLE, based on matching file names and timecodes. Other options, such as LUTs and burn-ins, plus native RED .r3d and ARRIRAW file support, are offered, which also makes SpeedGrade attractive for generating color-corrected dailies on set.

Remember, that if you get stumped, the F1 keyboard command brings up the Help documentation. To learn more about SpeedGrade, check out Adobe’s intro videos at Adobe TV.

Originally written for DV magazine / Creative Planet / NewBay Media, LLC

©2012 Oliver Peters

It starts at the camera

Modern color correction and grading systems allow you to performance a lot of magic in post. All too often though, producers take the “fix it in post” mantra way too seriously. Since modern cameras offer excellent low light sensitivity, the basics of good lighting and proper art direction get short-changed. If the director, DP and lighting crew are allowed a bit of time to exercise their craft, the results will be so much better in the end. Grading can make up for lighting deficiencies, but often at a cost of noise and color artifacts. Here are three basics to remember that will greatly improve your next production.

Exposure

Proper exposure is essential, but with improved low light sensitivity and an increased use of log-based gamma curves, operators often have a hard time deciding what the right exposure actually is. I’ve mocked up some images to help clarify some of my points. (Click on any of these images throughout this post for an enlarged view.)

Most log curves mathematically “bend” or “compress” the high-end and low-end range of what the sensor is picking up. It’s a way of squeezing a wide dynamic range into a recordable space. The typical mantra is to “expose to the right”. This can be interpreted as making the image brighter by setting the exposure so it displays in the bright section (the right side) of a histogram. In you expose too dark, you will effectively underexpose the image. When you try to make it brighter during color correction, you will increase noise, especially in the midrange. That’s because there’s not enough of an image to gracefully “stretch” without introducing artifacts, such as noise, posterization and banding.

To illustrate these points, I have taken this RED One shot and created various exposures from the raw file. These were then exported as “baked” ProRes files, which I subsequently graded using FCP X’s color board tool. I took the corner of the image into Photoshop and exaggerated the levels to make the defects in the dark area more obvious. If you review the larger images, you’ll see the one that started with the darkest simulated exposure as having the most posterized look, while the dark areas are smoothest in the shots that represented brighter lighting.

You want to be careful not to go too bright, since the opposite is also true. Highlights on hair make be too bright and you might have difficultly getting the image dark enough in the dark areas of the picture. Ideally, the image wants to cover an area on a histogram that’s roughly the middle third of the scale. On a waveform, skin values want to hit in the 50-60IRE range. This lets a colorist stretch up or down from there, without having to raise skin values “out of the mud”.

Contrast ratio

Next to having the image bright enough for good correction, you need to have some range to work with between the darkest and lightest portions of the picture. A typical waveform would show this as 0-100IRE, but that gets more difficult with log images, which start out considerably more washed out in appearance. Typically a 20-40 IRE spread in a log image, like ARRI Log-C or RED RedLogFilm, will yield excellent grading results, as these images attest.

Hue separation

One of the in-vogue looks is the “orange and teal” style popularized by blockbuster films and emulated by Magic Bullet Mojo and Looks. This is based on the color theory of various color models. But to get the look in a convincing way, you really need to start out with proper art direction. Skin tones tend to be pink-orange. If you shoot a very warm scene with an actor standing close to an orange wall, you’ve effectively set up a monochrome situation where all the hue values are the same and only saturation and brightness are changed. In that example, it’s very difficult to make the flesh tones and the wall color be different from each other. This can be fixed in the beginning by proper art direction and lighting.

A good place to go to understand and play with examples is Adobe’s Kuler website. The interactive color swatch tools are a good way of testing color schemes using scientific models of complementary colors, triads, etc.

©2012 Oliver Peters