ARRI ALEXA post, part 5

A commercial case study

Upon my return from NAB, I dove straight into post on a set of regional commercials for Hy-Vee, a Midwest grocer. I’ve worked with this client, agency and director for a number of years and all previous projects had been photographed on 35mm, transferred to Digital Betacam and followed a common, standard definition post workflow. The new spots featured celebrity chef Curtis Stone and instead of film, Director/DP Toby Phillips opted to produce the spots using the ARRI ALEXA. This gave us the opportunity to cut and finish in HD. Although we mastered in 1080p/23.98, delivery formats included 720p versions for the web and cinema, along with reformatted spots in 14×9 SD for broadcast.

The beauty of ALEXA is that you can take the Apple ProRes QuickTime camera files straight into edit without any transcoding delays. I was cutting these at TinMen, a local production company, on a fast 12-core Mac Pro connected to a Fibre Channel SAN, so there was no slowdown working with the ProRes 4444 files. Phillips shot with two ALEXAs and a Canon 5D, plus double-system sound. The only conversion involved was to get the 5D files into ProRes, using my standard workflow. The double-system sound was mainly as a back-up, since the audio was also tethered to the ALEXA, which records two tracks of high-quality sound.

On location, the data wrangler used the Pomfort Silverstack ARRI Set application to offload, back-up and organize files from the SxS cards to hard drive. Silverstack lets you review and organize the footage and write a new XML file based on this organization. Since the week-long production covered several different spots, the hope was to organize files according to commercial and scene. In general, this concept worked, but I ran into problems with how Final Cut Pro reconnects media files. Copying the backed-up camera files to the SAN changes the file path. FCP wouldn’t automatically relink the imported XML master clips to the corresponding media. Normally, in this case, once you reconnect the first file, the rest in a similar path will also relink. Unfortunately by using the Silverstack XML, it meant I had to start the reconnect routine every few clips, since this new XML would bridge information across various cards. Instead of using the Silverstack-generated XML, I decided to use the camera-generated XML files, which meant only going through the reconnect dialogue once per card.

It’s worth noting that the QuickTime files written by the ARRI ALEXA somehow differ from what FCP expects to see. When you import these files into FCP, you frequently run into two error prompts: the “media isn’t optimized” message and the “file attributes don’t match” message. Both of these are bogus and the QuickTime files work perfectly well in FCP, so when you encounter such messages, simply click “continue” and proceed.

Click for an enlarged view

Dealing with Log-C in the rough cut

As I’ve discussed in numerous posts, one of the mixed blessings of the camera is the Log-C profile. It’s ARRI’s unique way of squeezing a huge dynamic range into the ALEXA’s recorded signal, but it means editors need to understand how to deal with it. Since these spots wouldn’t go through the standard offline-online workflow, it was up to me as the editor to create the “dailies”. I’ve mentioned various approaches to LUTs (color look-up tables), but on this project I used the standard FCP color correction filter to change the image from its flat Log-C appearance to a more pleasing Rec 709 look. On this 12-core Mac Pro, ProRes 4444 clips (with an unrendered color correction filter applied) played smoothly and with full video quality on a ProRes HQ timeline. Since the client was aware of how much better the image would look after grading – and because in the past they had participated in film transfer and color correction sessions – seeing the flat Log-C image didn’t pose a problem.

From my standpoint, it was simply a matter of creating a basic setting and then quickly pasting that filter to clips as I edited them to the timeline. One advantage to using the color correction filter instead of a proper LUT, is that this allowed me to subjectively tweak a shot for the client, without adding another filter. If the shot looked a little dark (compared with a “standard” setting), I would quickly brighten it as I went along. Like most commercial sessions, I would usually have several versions roughed in before the client really started to review anything. In reality, their exposure to the uncorrected images was less frequent than you might think. As such, the “apply filter as you go” method works well in the spot editorial world.

Moving to finishing

New Hat colorist Bob Festa handled the final grading of these spots on a Filmlight Baselight system. There are a couple of ways to send media to a Baselight, but the decision was made to send DPX files, which corresponded to the cut sequence. Since I was sending a string of over ten commercials to be graded, I had a concern about the volume of raw footage to ship. There is a bug in the ALEXA/FCP process and that has to do with FCP’s Media Manager. When you media manage and trim the camera clips, many are not correctly written and result in partial clips with a “-v” suffix. If you media manage, but take the entire length of a clip, then FCP’s Media Manager seems to work correctly. To avoid sending too much footage, I only sent an assembled sequence with the entire series of spots strung out end-to-end. I extended all shots to add built-in handles and removed any of my filters, leaving the uncorrected shots with pad.

Final Cut Pro doesn’t export DPX files, but Premiere Pro does. So…  a) I exported an XML from FCP, b) imported that into Premiere Pro, and c) exported the Premiere Pro timeline as DPX media. In addition, I also generated an EDL to serve as a “notch list”, which lined up with all the cuts and divided the long image sequence into a series of shots with edit points – ready to be color corrected.

After a supervised color correction session at New Hat, the graded shots were rendered as a single uncompressed QuickTime movie. I imported that file and realigned the shots with my cuts (removing handles) to now have a set of spots with the final graded clips in place of the Log-C camera footage.

Of course, spot work always involves a few final revisions, and this project was no exception. After a round of agency and client reviews, we edited for a couple of days to revise a few spots and eliminate alternate versions before sending the spots to the audio mixing session. Most of these changes were simple trims that could be done within the amount of handle length I had on the graded footage. However, a few alternate takes were selected and in some cases, I had to extend a shot longer than my handles. This combination meant that about a dozen shots (out of more than ten commercials) had to be newly graded, meaning a second round at New Hat. We skipped the DPX pass and instead sent an EDL and the raw footage as QuickTime ProRes 4444 camera files for only the revised clips. Festa was able to match his previous grades, render new QuickTimes of the revised shots and ship a hard drive back to us.

Click to view “brand introduction” commercial

Reformatting

Our finished masters were ProRes HQ 1920×1080 23.98fps files, but think of these only as intermediates. The actual spots that run in broadcast are 4×3 NTSC. Phillips had framed his shots protecting for 4×3, but in order to preserve some of the wider visual aspect ratio, we decided to finish with a 14×9 framing. This means that the 4×3 frame has a slight letterbox with smaller top and bottom black bars. Unlike the usual 4×3 center-crop, a smaller portion of the left and right edge of the 16×9 HD frame is cropped off. I don’t like how FCP handles the addition of pulldown (to turn 23.98 into 29.97 fps) and I’m not happy with its scaling quality to downconvert HD to SD. My “go to” solution is to use After Effects as the conversion utility for the best results.

From Final Cut, I exported a self-contained, textless QuickTime movie (HD 23.98). This was placed into an After Effects 720 x 486 D1 composition and scaled to match a 14×9 framing within that comp. I rendered an uncompressed QuickTime file out of After Effects (29.97 fps, field-rendered with added 3:2 pulldown). The last step was to bring this 720 x 486 file back into FCP, place it on an NTSC 525i timeline, add and reposition all graphics for proper position and finish the masters.

Most of these steps are not unusual if you do a lot of high-end spot work. In the past, 35mm spots would be rough cut from one-light “dailies”. Transfer facilities would then retransfer selects in supervised color correction sessions and an online shop would conform this new film transfer to the rough cut. Although many of the traditional offline-online approaches are changing, they aren’t going away completely. The tricks learned over the past 40 years of this workflow still have merit in the digital world and can provide for rich post solutions.

Sample images – click to see enlarged view

Log-C profile from camera

Nick Shaw Log-C to Rec 709 LUT (interface)

Nick Shaw Log-C to Rec 709 LUT (result)

Final image after Baselight grading

© 2011 Oliver Peters

ARRI ALEXA post, part 4

Local producers have started real productions with the ARRI ALEXA, so my work has moved from the theoretical to the practical. As an editor, working with footage from ALEXA is fun. The ProRes files are easily brought into FCP, Premiere Pro or Media Composer via import or AMA with little extra effort. The Rec 709 color profile looks great, but if the DP opts for the Log-C profile, grading is a snap. Log-C, as I wrote before, results in an image akin to a film scan of uncorrected 35mm negative. It’s easy to grade and you end up with gorgeous natural colors. There’s plenty of range to swing the image in different ways for many different looks.

Working with the Log-C profile in front of a client takes a bit of strategy, depending on the NLE you are using. Under the best of circumstances, you’d probably want to process the images first and work with offline-resolution editing clips (like Avid DNxHD36 or Apple ProRes Proxy) with a color correction LUT “baked” into the image. Much like one-light “dailies” for film-originated projects.

Many projects don’t permit this amount of advanced time, though, so editors often must deal with it as part of the edit session. This primarily applies to commercial and corporate work. Workflows for feature film and TV projects should follow a more traditional course, with prep time built into the front end, but that’s another blog post.

Strategies

There are LUT (color look-up table) filters for FCP, but unfortunately real-time performance is challenged by many. The best performance, is when you can use the native filters, even though that might not technically be the correct curve. That’s OK, because most of the time you simply want a good looking image for the client to see while you are doing the creative cut. Apple Final Cut Pro and Adobe Premiere Pro both require that you apply a filter to each clip on the timeline. This has an impact on your workflow, because you have to add filters as you go.

One good approach, which balances FCP performance with an accurate LUT, is the Log-C to Rec 709 plug-in developed by Nick Shaw at Antler Post. It not only corrects the profile, but adds other features, like “burn-in” displays. If you leave your FCP timeline’s RT setting in dynamic/dynamic, the unrendered clips with this filter applied will drop frames. Changing the setting to Full frame rate and/or High/Full will yield real-time playback at full video quality on a current Mac.

ARRI has enabled its web-based LUT Generator, which is accessible for free if you register at the ARRIDIGITAL site. You can create LUTs in various formats, but the one that has worked best for me is the Apple Color .mga version. This can be properly imported and applied in Apple Color. There it may be used simply for viewing or optionally baked into the rendered files as part of the color correction.

You can also use Red Giant’s free Magic Bullet LUT Buddy. This filter can be used to create and/or read LUTs. Apply it to a clip in Final Cut Pro, Premiere Pro or After Effects, read in the .mga file and render. Lastly, the Adobe apps also include a Cineon conversion filter. Apply this in Premiere Pro or After Effects and tweak as needed. On a fast machine, Premiere Pro CS 5.5 plays clips with the Cineon converter applied, in real-time without rendering.

Avid Media Composer and Adobe After Effects currently have the best routines, because you can add color correction to an upper layer and everything underneath is adjusted.

After Effects actually treats this as an “adjustment layer”, like in Photoshop, while Media Composer simply lets you add filters to a blank track – effectively doing the same thing as an adjustment layer. You still won’t see the source clip as a corrected image, but once it is placed on the timeline, the correction is applied and the image appears richer.

In the case of Avid Media Composer, this can also include some filters other than its own color correction mode filters. For example, GenArts Sapphire or Magic Bullet Looks. Media Composer is able to play these files at full quality, even though they are unrendered, giving it a performance edge over FCP.

Cutting spots in Log-C

I recently cut a set of national spots for Florida Film & Tape (a local production company) on a late-model Apple dual-processor PowerMac G5, running FCP 6.0.6. It was equipped with a fast SCSI RAID and an AJA Kona card. That’s a perfectly good set-up for most SD and HD post. In fact, I’ve previously edited spots photographed on 35mm film and the RED One camera for the same client and same production company on this system. G5s were manufactured and sold before ProRes was ever released; but, in spite of that, I was able to work with the 1920×1080 23.98fps ProRes4444 files that were shot. I placed my selected clips on an uncompressed timeline and started cutting. The client had already seen a Rec 709 preview out of the camera, so he understood that the image would look fine after grading. Therefore, there was no need to cut with a corrected image. That was good, because adding any sort of color correction filter to a large amount of footage would have really impacted performance on this computer.

In order to make the edit as straightforward and efficient as possible, I first assembled a timeline of all the “circle takes” so the director (Brad Fuller) and the client could zero in on the best performances. Then I assembled these into spots and applied a basic color correction filter to establish an image closer to the final. At this point, I rendered the spots and started to fine-tune the edit, re-rendering the adjustments as I went along. This may sound more cumbersome than it was, since I was editing at online quality the entire time (uncompressed HD). Given the short turnaround time, this was actually the fastest way to work. The shoot and post (edit, grade, mix) were completed in three consecutive days!

Once the picture was locked, I proceeded to the last steps – color grading the spots and formatting versions for various air masters. I decided to grade these spots using the Magic Bullet Colorista (version 1) plug-in. There was no need to use Apple Color and Colorista works fine on the G5. I removed the basic filter I had applied to the clips for the edit and went to work with Colorista. It does a good job with the Log-C images, including adding several layers for custom color-correction masks. As flat as the starting images are, it’s amazing how far you can stretch contrast and increase saturation without objectionable noise or banding.

I’ll have more to write about ALEXA post in the coming weeks as I work on more of these projects. This camera has garnered buzz, thanks to a very filmic image and its ease in post. It’s an easy process to deal with if your editing strategy is planned out.

©2011 Oliver Peters

Cool Tools for Spring

Time to catch up on a few items that will improve your editing and make your daily tasks easier.

(Click on the images below for an enlarged view.)

DiscCatalogMaker

Editors are increasingly using inexpensive hard drives as a method of archiving. But how do you keep track of where your files are? As I started to look around, I realized I already owned a very functional utility, simply because I had Roxio’s Toast. One of the extra applications installed and in the folder is DiscCatalogMaker RE. It automatically catalogs all of the discs you’ve ever burned, but it can also be used to index hard drives. Simply start a new catalog and have it scan a target drive. This file can be saved and printed. It’s also searchable, so you can easily find files without mounting the drive. Once you add/delete/change files on the drive, just rescan it and re-save the updated file.

Red Giant Software Magic Bullet PhotoLooks

If you like Magic Bullet Looks and you do a lot of work with stills, then check out PhotoLooks. I touched on this in my Stocking Stuffers post, but it’s worth another mention. Like Looks for video applications, PhotoLooks runs in an external LooksBuilderPL application that is optimized for stills. PhotoLooks works as a plug-in for Photoshop, Aperture and Lightroom and uses the same chain of tools as the video version. As you can see in this Alamo photo, it’s quite easy to create very stylized still photos in post.

Digital Film Tools PhotoCopy

At first glance, PhotoCopy might seem like it’s doing the same functions as Magic Bullet Looks, but that would be wrong. Like Looks, the plug-in launches a separate, customized interface, but that’s where the similarities end.  DFT PhotoCopy uses representative samples from movies, paintings, photographs, etc. to apply color correction and texture to your target photo or video clips.

These can work like color grading presets – or in the case of paintings – apply brush strokes and texture to the image. This isn’t just a simple overlay. PhotoCopy does an analysis of the target image, in order to intelligently apply the right effect or colors to the appropriate positions within the shot. These can be further adjusted by slider controls in the interface. PhotoCopy runs in Final Cut Pro, Media Composer, After Effects, Photoshop, Aperture and Lightroom; however, different licenses must be purchased for the motion and the still photo versions of the tool.

Nick Shaw ALEXA Look-Up Tables (LUTs)

As editors start to wrap their heads around post workflows for the ARRI ALEXA camera, the biggest issue seems to be the best method of converting the Log-C profile recorded by the camera into nice-looking Rec. 709 images for the client. Log-C images are viewable, but appear flat and washed out prior to grading. UK-based post consultant Nick Shaw has developed a set of FCP plug-ins designed to convert Log-C images into Rec. 709. They include a few extra features, like saturation boost and timecode/text burn-in fields. For now, these are considered to be “preview” quality, since the LUTs truncate the bit-depth to an 8-bit scale. The current paid version supports the camera’s 3.0 firmware.

Luca Visual FX

I’ve covered the Luca Visual FX tools a few times in my color grading posts. Their plug-ins are offered as part of the FxFactory product line. In addition to plug-ins, Luca Visual FX also offers a set of Film FX and Light Transitions. They have recently released the Film FX 2.0 package. Unlike the plug-ins, these tools are a set of QuickTime movie files using the Animation codec with an alpha channel. As such, they can be used with nearly any NLE or motion graphics application and aren’t dependent on a specific plug-in architecture. In the case of Final Cut or Media Composer, simply place a clip on an upper track and the rest is done. In the previous post, I covered some ways in which these can be used with different fills or by combining several clips for a custom effect. The Film FX 2.0 package adds more grunge to the options in Film FX 1.0 for new and dynamic effects.

Noise Industries FxFactory Manifesto

A better Final Cut Pro title tool and it’s free. What’s not to like? Noise Industries launched Manifesto – a lightweight, yet powerful title generator – as part of the FxFactory toolset. It installs as two generator plug-ins – one for static titles and another for rolls and crawls. Text composition is very easy and the plug-in draws on many of the built-in frameworks of Mac OSX, such as fonts, colors and spell-checking. You can also import existing RTF files and Manifesto will use the formatting of that file.

Focusrite Scarlett

Another tool I touched on in the Stocking Stuffers post was the Focusrite Scarlett software filters suite. This set of four audio plug-ins (EQ, compressor, gate, reverb) installs in VST/AU and RTAS formats. On a Mac, they’ll work in most DAWs, as well as Media Composer (5, 5.5) and Final Cut Pro (sliders only – no custom GUI). These filters are designed to look and sound like their classic hardware brethren. In general, they run best in Avid Pro Tools, Adobe Audition and Apple Soundtrack Pro and provide a reasonably-priced filter package for those who want to go beyond the healthy set of options already included with these applications. Focusrite also sells other software plug-in products, including Midnight, Forte, Guitar FX and more.

Noise Industries FxFactory Photo Montage

Noise Industries just introduced a great new tool for assembling photographic montage sequences, called simply Photo Montage. There are several of these on the market, but the Noise Industries version is easy to use and offers plenty of presets, as well as many ways to customize the style, moves, transitions and other attributes. Like most of their plug-ins, Photo Montage is GPU-accelerated and works in Final Cut Pro, Final Cut Express, Motion and After Effects. It supports most common image formats including JPEG, PNG and PSD, so getting started is as easy as applying one of the generator effects, choosing the source image folder and applying a preset. From there, you can re-order the stills, alter the animation parameters and so on.

Digital Heaven Final Print 2.0

Many of Digital Heaven’s tools are designed around improving the editor’s efficiency and taking some of the drudgery out of non-editorial tasks. Often editors have to supply reports to clients, marker list print outs and more. A helpful application is Final Print, which has just been updated to version 2.0. You can start with XML files or directly load projects from FCP7. Final Print 2.0 will not only display various marker lists (which can be filtered by color), but also sequence lists complete with thumbnails and timecode. If you need to generate various reports out of Final Cut Pro – such as the director’s notes from marker text – Final Print 2 provides one of the best and most attractive ways to do that.

©2011 Oliver Peters

ARRI ALEXA post, part 3

Post Workflow – Avid Media Composer 5

Thanks to Avid Media Access (AMA), the Media Composer application starting with version 5 can natively handle Apple ProRes media. This means you can bring in files from an ARRI ALEXA and immediately start editing. But ProRes 422 (HQ) or ProRes 4444 might be more taxing than you want to deal with on a long project, so I’m going to outline a suggested workflow for an ALEXA project using Avid Media Composer 5.

Step 1. Same as step 1 in the previous FCP post – clone your media files for protection. Standard archiving solutions include LTO data tape, redundant copies on hard drive or burning media to Blu-ray discs (BR-ROM).

Step 2. Import the camera masters (ProRes HQ or ProRes 4444) into a Media Composer project, using “Link to AMA Files (or Volume)”.

Step 3. Determine the selected takes you plan to edit with and transcode these AMA clips to Avid media. If you intend to use these for just rough cut, creative editing, then select the DNxHD 36 resolution. Move the transcoded files to a separate bin. Close the bin with the AMA clips and do not use these as sources in your edit.

Step 4. Edit as you normally would with the DNxHD 36 clips. Feel free to change clip names as appropriate. I am going to assume that the ALEXA clips used the Log C profile, which means that they are low-contrast in appearance. For the purpose of client/producer viewing, you may need to apply a basic color effect filter to an upper track in order to provide a basic adjustment to make these clips appear more like “normal” video. Edit until the cut is locked and approved.

Step 5. Once the cut is locked, hide the transcoded media by moving the corresponding Avid media files out of the MXF folder on your media hard drive. This will cause the clips in your sequence to be offline.

Step 6. Open the AMA bins (with the ProRes files) and relink the edited sequence to the AMA clips. When relinking is complete, the sequence will be repopulated with AMA media, which will be the native files.

Step 7. Consolidate/transcode your sequence. Select a higher resolution, such as DNxHD 175X. This will create new Avid media clips at full quality for all clips in your timeline.

Click on the image for an enlarged view. (Alexa clip courtesy of ARRI.)

Step 8. Remove any temporary color effect you might have added before. Enter the Avid color correction mode for final grading. As I previously discussed with Color, one approach is to use the auto-contrast controls to change black and white points. Apply this first and increase the master saturation to 150 as a basic starting point. Then proceed to do your creative grading using the hue offset and curve controls. Just as in Color, this automatic control is only calculated on the parked frame, so tweak as needed.

An interesting hybrid approach to posting ALEXA files is to combine elements of these Final Cut and Media Composer workflows. For example, you could use FCP and the Nick Shaw LUT plug-in to create editing proxy files. Export one set of files from FCP with the LUT and timecode burned-in. Bring those in via AMA and follow the steps outlined above for the rough cut.

Then, when it comes to the finishing steps, use AMA to import the original camera files and link your sequence to those clips instead of the ones with the LUT and burn-in. The one caveat to proper relinking is to make sure the source file names match, including extensions. Both the original files and the exported “baked” files need to match with regards to the presence or absence of the .mov file extension. It may take a bit up trial-and-error for you to get the hang of it, but this hybrid solution will work just fine!

©2010 Oliver Peters

ARRI ALEXA post, part 2

Post Workflow – Apple Final Cut Pro

Posting ARRI ALEXA’s ProRes clips is going to follow many of the established workflows. The fact that it’s a new camera doesn’t really make much difference. The camera generates direct-to-edit ProRes media with embedded timecode and reel IDs. These are self-contained files without a folder hierarchy to mess you up, like with P2 or XDCAM. These media files are immediately ready to edit with most modern NLEs, including Apple Final Cut Pro 7, Adobe Premiere Pro CS5 and Avid Media Composer 5 (via AMA). Assuming that these camera clips are intended as the master files, then “best practices” for tapeless workflows need to be followed to archive and protect the media. These files are your “electronic negative”.

You could, of course, immediately edit natively with these clips, but instead, I’m going to lay out an offline-online workflow using ARRI ALEXA clips. Since these master clips might be ProRes 4444 or ProRes (HQ), many editors would rather deal with smaller proxy editing files during the creative, rough cutting phase of a project.

For the sake of this exercise, I’m going to assume that the files are recorded using the ALEXA Log C profile. This yields a low-contrast, “flat” image designed to preserve dynamic range and offer optimum grading latitude. It’s a wonderful alternative to true camera raw recording, but adds a few considerations for post.

Step 1. Clone your media files for protection. Standard archiving solutions include LTO data tape, redundant copies on hard drive or burning media to Blu-ray discs (BR-ROM). Here is also a step-by-step guide from Abel Cine Tech about how to offload the cards for FCP editing.

Step 2. Import the camera masters (ProRes HQ or ProRes 4444) into an FCP project.

Step 3. Drag-and-drop all of your clips to a new sequence. Apply Nick Shaw’s custom ALEXA LUTs to the timeline clips. This is an FxScript FCP plug-in with an optional burn-in window for text and timecode. Use the version of the filter that matches the exposure index to which the camera was set during recording. Now select all the clips in the timeline and drag them to a new, empty bin. This will create subclips with the embedded plug-in (LUT + burn-in).

Step 4. Set up a Batch Export of these subclips. Change the export settings to a different codec, such as ProRes 422 (Proxy), DVCPROHD or anamorphic DV. The exported clips will now become your editing proxy media.

Step 5. Create a new FCP project (optional) and import the folder of exported clips. These will become your working clips for the rough cut. These will have the LUT and burn-in data “baked” into the file.

Step 6. Edit as you normally would until the cut is approved and locked.

Step 7. When the cut is locked, create a new FCP project (optional) and copy the sequence for the locked cut to the new project. Make the sequence clips independent and reconnect the files to the original camera master media. Of course, these clips no longer have the LUT or burn-in applied. Change the sequence settings to match the desired final quality. Adjust any graphics, images and text as needed. Use “send to Color” to move the FCP timeline into Color for final grading.

Step 8. Follow a standard Color grading routine for the sequence. Since there is no corresponding Color LUT for ALEXA files, yet, you will have to establish the correct base look in Color before adding any additional grading. Once the grading is done, render and send back to FCP.

I would recommend, setting a basic conversion grade in Color’s Primary In room that can be applied to all clips. This corrects the Log C profile. Then use the Secondary windows as full-screen “adjustment layers” for all of your normal grading tasks. An alternate approach is to use the Auto Balance control in the Primary In room. I don’t usually think much of such automatics, but it seemed to do a  good job with the ALEXA Log C clips that I tested. Apply it first, which changes the lift/gamma/gain values in the Primary – Advanced tab. Then alter the Primary – Basic saturation value to 1.5. Now you have a good starting point and can still use the curves and hue offset controls (“color wheels”) in the Primary room as you normally would.

Click on the image for an enlarged view. (Alexa clip courtesy of ARRI.)

Remember, that you are not applying a true LUT, since the adjustments you are making – even the automatic ones – are based on the levels for the frame on which you are parked. If a shot moves from bright sun to shade, then setting Auto Balance for the bright sunlit segment will cause the shaded portion to have crushed blacks, as well as the other way around. Be prepared to tweak as needed.

ARRI Digital will soon post a page with a LUTs Generator, which might alter this workflow in the future. Also check out ARRI-specific products at GlueTools.

©2010 Oliver Peters